Impact of Interpregnancy Interval after Caesarean Section on Perinatal Outcomes in Multiparous Women of Advanced Maternal Age: A Retrospective Cohort Study

Impact of Interpregnancy Interval after Caesarean Section on Perinatal Outcomes in Multiparous Women of Advanced Maternal Age: A Retrospective Cohort Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Impact of Interpregnancy Interval after Caesarean Section on Perinatal Outcomes in Multiparous Women of Advanced Maternal Age: A Retrospective Cohort Study shengping zhou, li dai, Qin Xu, Lei Ye, qilin wang, Rong Zhou This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4089431/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: This study aims to evaluate the impact of different interpregnancy intervals (IPIs) after a previous caesarean section on perinatal events in elderly multiparous women. Methods: In this retrospective cohort study, multiparous women of advanced maternal age who had a previous caesarean section between January 1, 2016, and December 31, 2016, were included.IPI was defined as the duration between live birth and subsequent conception.Multivariate logistic regression analysis was used to assess the association between variant IPIs (<24 months, 60-119 months, and ≥120 months) and perinatal outcomes, with an IPI of 24-59 months as the reference group.The risks of anemia, gestational hypertension, gestational diabetes mellitus,placenta previa,premature rupture of membrane,uterine rupture and successful vaginal were compared among the 4 groups. Results: We recorded a total of 591 births following cesarean delivery: 16, 89, 290, and 196 births in the IPI < 24 months, 24-59 months, 60-119 months, and ≥120 months groups, respectively. Women with an IPI of ≥120 months had a significantly higher incidence of gestational hypertension (6.1%, p＜0.001) than the other three groups. In women with a prior caesarean delivery and an IPI＜ 24 months, there was an increased risk of incomplete uterine rupture (OR 1.89, 95% CI 1.13-1.87) and low 1-minute Apgar scores (OR 1.55, 95% CI 0.45-4.63). The IPI did not impact the occurrence of incomplete uterine rupture in women with a history of emergency caesarean section.There was no significant association between the IPI and other adverse perinatal outcomes, such as anaemia, gestational diabetes mellitus,abnormal placental position, pernicious placenta, placenta accreta, placental abruption, postpartum haemorrhage, hysterectomy, or neonatal intensive care admission.An IPI <24 months was associated with higher likelihood of premature rupture (OR 1.97, 95%CI 0.58-10.2). Conclusion: Women with an IPI of ≥120 months had a higher rate of gestational hypertension compared to the other groups, while an IPI of <24 months increased the risk of incomplete uterine rupture and low 1-minute Apgar scores. Interpregnancy interval Caesarean delivery Perinatal outcomes Advanced maternal age Caesarean section Figures Figure 1 Background According to the recommendations of the World Health Organization (WHO), it is advised to wait at least two years between a previous live birth and the subsequent conception, regardless of the mode of delivery 1 . In 2016, the implementation of Chinese revised two-child policy has led to a significant increase in the number of multiparous women 2 .This has also highlighted the emerging issue of scar uterus re-pregnancy and associated delivery complications resulting from Chinese high rate of caesarean sections（CSs） 3 . An increasing number of families, who had chosen CS for their first child, are now confronted with the choice of having a second child. As a result, managing a growing number of high-risk parturients with multiple risk factors, including advanced maternal age(AMA), long IPI, and previous CS, has become challenging for obstetricians in China. These risk factors have been shown to increase the likelihood of adverse pregnancy outcomes, such as placenta previa 4 ,uterine rupture 5,6 ,gestational hypertension (GHP) 7,8 ,gestational diabetes mellitus (GDM), preterm delivery, low birth weight (LBW), and neonatal intensive care unit (NICU) admission 2,9 -14 . In our previous systematic review, we examined the relationship between IPI and adverse pregnancy outcomes in women who had previously undergone a CS. We observed associations between IPI and risks of uterine rupture, success of vaginal birth after CS (VBAC), and placenta previa 15 . Due to variations in the measurement and categorization of birth spacing in previous studies, we were unable to determine the optimal IPI after CS. Furthermore, the implementation of the two-child policy in China following the 36-year-long one-child policy has led to a significant increase in the number of pregnant women with long IPIs. Given the unique circumstances related to family planning policies and diverse patterns of pregnancies and deliveries in China, it was necessary to conduct a specific study on Chinese women. To address this gap, we conducted a large retrospective cohort study to investigate the association between IPI after previous CS and adverse pregnancy outcomes. Methods This retrospective cohort study was conducted at West China Second University Hospital, Sichuan University, which is a tertiary care hospital. The study specifically targeted older women(defined as being 35 years or older at the time of delivery) with a history of CS who gave birth at our hospital between January 2016 and December 2016. Data for the study were collected from the electronic medical system and supplemented with information from medical records. Two trained abstractors were assigned to review the abstract data obtained from the medical charts. The study received ethical approval from the Ethics Committee and Data Inspectorate of West China Second University Hospital, Sichuan University (No. 2016(010)). Our primary analysis included all women with a history of at least one previous caesarean delivery (CD) who gave birth between 28 and less than 42 weeks of gestation. We excluded women who met the following criteria: (1) had undergone uterine surgery other than caesarean section, (2) did not receive routine antenatal care, (3) had multiple pregnancies, and (4) had fetal malformations. IPI in this study was defined as the duration between the date of the last caesarean section and the conception date of the subsequent delivery. The IPI was estimated by subtracting the gestational age at birth from the delivery date of the index pregnancy. For the purpose of analysis, the IPI was categorized into four groups: less than 24 months, 24-59 months, 60-119 months, and 120 months or greater. Maternal outcomes assessed in this study included anaemia in late pregnancy (defined as a haemoglobin concentration below 110 g/L between 32 and 42 weeks of gestation) 16 ,GHP (in accordance with the consensus statement from the International Society of Study of Hypertension in Pregnancy（ISSHP）) 17 ,GDM categorized as Grade A1 (indicating well-controlled blood glucose through non-drug therapy) or Grade A2 (indicating the need for medically controlled blood glucose as per WHO criteria) 18 , abnormal placental position, pernicious placenta, placenta accreta, placental abruption, premature rupture (PROM), uterine rupture (classified as incomplete or complete rupture detected during caesarean section by experienced obstetricians) 19 ,postpartum haemorrhage (PPH), and hysterectomy. Adverse fetal outcomes assessed included preterm birth, admission to the NICU, low 1-minute Apgar score (defined as an Apgar score less than 10 evaluated 1 minute after birth by a professional obstetrician), and LBW( defined as a birth weight less than 2500 g). To account for potential confounding variables, such as demographic and clinical characteristics that may vary among the four IPI groups and influence the association between IPI and perinatal outcomes, multivariable logistic regression analysis models were developed. These models were used to adjust for the impact of IPI following a CS on adverse maternal and fetal outcomes. Additionally, since previous research has indicated that emergency CS significantly increases the risk of adverse perinatal outcomes 20 ,multivariate logistic regression models were established to analyse the relationship between IPI and perinatal outcomes separately for emergency and elective CS cases. Sociodemographic characteristics and adverse pregnancy outcomes were compared among the four IPI groups using the chi-square test for categorical variables and conducting a one-way analysis of variance for continuous variables. Multivariable logistic regression analysis was then performed for each pregnancy outcome to examine the association between different IPIs while controlling for known and suspected confounding factors. An IPI of 24-59 months was used as the reference category, following the guidelines of the WHO 1 . Data analysis was conducted using SPSS Statistics version 21.0 for Windows (SPSS Inc., Chicago, IL, USA). A significance level of p<0.05 (two-tailed) was considered statistically significant. Results A total of 655 deliveries by women with advanced maternal age and a history of CS were documented at the West China Second University Hospital between January 1, 2016, and December 31, 2016. After applying the exclusion criteria, 64 women were excluded: 17 due to lack of routine antenatal care, 28 due to multiple pregnancies, 13 due to fetal malformation, and 6 due to uterine surgery other than CS. The final sample size for this retrospective cohort study included 591 women, who were then categorized into four groups based on different IPIs: 16 women with an IPI of less than 24 months, 89 women with an IPI of 24-59 months, 290 women with an IPI of 60-119 months, and 196 women with an IPI of 120 months or longer (Figure 1). The average age at delivery for all cohorts was 36.8 years, and there were no significant differences among the four groups (Table 1). However, women with an IPI of 120 months or more had a higher prevalence of gravidity (number of pregnancies) of three or more compared to the other three groups. Additionally, this group had a lower prevalence of parity (number of live births) of two or more and a lower prevalence of prior CS of two or more with indications. There were also significant differences among the four groups in terms of educational status distribution (p < 0.001). Women with an IPI of less than 24 months had a history of two or more CS compared to the other three groups (p < 0.001). There were no significant differences in maternal body mass index (BMI), history of vaginal delivery, use of in vitro fertilization and embryo transfer (IVF-ET), presence of chronic hypertension or pregestational diabetes mellitus (PGDM), and gestational age at delivery among the four groups. Only 3.2% (n = 19) of the women achieved a VBAC, and the rates of emergency CS and CS with indications did not differ among the four groups. Women with an IPI of 120 months or longer had a higher rate of GHP compared to the other three groups (6.1%, p < 0.001). However, no significant differences were found among the four groups in terms of other maternal outcomes, such as anaemia, GDM, low placenta, placenta previa, pernicious placenta, placenta accreta, placental abruption, PROM, PPH, and hysterectomy. Similarly, no significant differences were observed among the four groups in terms of perinatal outcomes, including preterm birth, delivery before 34 weeks of gestation, birth weight, birth length, low 1-minute Apgar score, LBW, or admission to the NICU (Table 2). Multivariate logistic analysis was conducted using an IPI of 24-59 months as the reference category to examine the associations between different IPIs and adverse perinatal outcomes. Results from Table 3 indicate that an IPI of 120 months or longer was associated with an increased risk of developing GHP in late pregnancy (adjusted odds ratio (aOR) 16.223, 95% CI 2.73-96.33, p=0.002). On the other hand, an IPI of less than 24 months or 60-119 months was associated with a decreased risk of GHP in the third trimester (IPI of less than 24 months, aOR 0.688, 95% CI 0.17-2.77, p=0.598; IPI of 60-119 months, aOR 0.932, 95% CI 0.43-5.20, p=0.472). An IPI of less than 24, 60-119, or 120 months did not have a significant effect on the risk of developing anaemia and GDM. Results from the analysis revealed that an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture (OR1.89, 95% CI 1.13-1.87). On the other hand, an IPI of 60-119 months (OR 0.61, 95% CI 0.05-6.82) and 120 months or longer (OR 0.91, 95% CI 0.08-10.14) significantly reduced the risk of incomplete uterine rupture. Additionally, an IPI of less than 24 months significantly increased the risk of low 1-minute Apgar scores (Table 4). After adjusting for educational status, number of previous pregnancies, parity, and prior caesarean section, the results suggested that IPI was not a risk factor for incomplete uterine rupture (Table 5). Regardless of whether confounders were adjusted, IPI did not have an impact on other adverse perinatal outcomes, such as pernicious placenta, abnormal placental position, PROM, PPH, hysterectomy, and admission to the NICU. Several studies have shown that emergency CS can increase the risk of adverse perinatal outcomes 21 . In this study, we conducted a multivariable logistic regression analysis to examine the relationship between IPI and perinatal outcomes among 201 women with a history of emergency CS and 168 women with selective CS. The analysis revealed that IPI in women with a history of emergency CS was not significantly associated with the occurrence of uterine rupture (p > 0.05) (Table 6; Table 7). In women with a history of CS, IPI was found to be a risk factor for incomplete uterine rupture (p=0.028) and PROM (p = 0.015). Specifically, an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture (OR 1.25, 95% CI 0.81-8.92), while an IPI of 60-119 months (OR 0.29, 95% CI 0.02-4.66) and 120 months or longer (OR 0.44, 95% CI 0.03-7.14) significantly reduced the risk of incomplete uterine rupture. An IPI of less than 24 months was associated with an increased risk of PROM (OR 1.97, 95% CI 0.58-10.2), while an IPI of 60-119 months (OR 0.64, 95% CI 0.21-2.15) and 120 months or longer (OR 0.76, 95% CI 0.21-2.72) significantly reduced the risk of PROM. After adjusting for confounders such as educational status, number of previous pregnancies, parity, and prior CS, the IPI in women with a history of selective CS was not found to be a significant risk factor for incomplete uterine rupture (p = 0.996) and PROM (p = 0.637) (Tables 8 and 9). Discussion In our study, we found that IPI had an impact on adverse pregnancy outcomes in patients with GHP during late pregnancy. We did not observe any significant effects of IPI (less than 24 months, 60-119 months, or 120 months or longer) on the risk of developing anaemia and GDM. There were no significant differences among the four groups when it came to perinatal outcomes such as preterm birth, delivery before 34 weeks of gestation, birth weight, birth length, low 1-minute Apgar score, LBW, or admission to the NICU. The rate of trial of labour after caesarean (TOLAC) was 3.2% (n = 19). The birth spacing may have an impact on perinatal outcomes due to its potential effects on maternal health and nutrient concentrations. The recovery period following a CS is typically longer compared to vaginal delivery. Previous studies have shown that for mothers aged 35 years or older, longer IPIs (60 months) were associated with an increased risk of preeclampsia compared to intervals of 18 months 22,23 . Other research has found that IPIs less than 6 months, 6-11 months, and 12-17 months were significantly protective against GDM, GHP, and maternal morbidity compared to an interval of 18-23 months 24 .In our study, we found that an IPI of 120 months or longer increased the risk of GHP in late pregnancy. This association may be attributed to the fact that pregnant women with longer IPIs tend to be older, which is a known risk factor for adverse pregnancy outcomes 25 .It has been reported that the association between IPI and adverse outcomes disappears when common confounders are taken into account.In our study, we did not find an association between an IPI of less than 24 months and an increased risk of adverse neonatal outcomes, such as preterm birth, low 1-minute Apgar score, LBW, and admission to the NICU. Several studies have reported on the association between birth spacing and adverse neonatal outcomes 26 , but there has been limited research specifically focusing on women with a history of CS. A meta-analysis conducted in 2006 among multiparous women found that an IPI shorter than 18 months and longer than 60 months had the highest risk for preterm birth and LBW 26 .Moreover, Class et al. conducted a study using cousin and sibling comparisons, which demonstrated that an IPI of 60 months or more was associated with increased risks for preterm delivery (before 37 weeks) and LBW 27 .Given the substantial increase in women with extremely long IPIs following the revised reproductive policy in China, in our study, we specifically analysed the association between adverse perinatal outcomes and an IPI of 120 months or longer, which was not explored in non-Chinese research. Zhu et al. 28 proposed the concept of "physiological regression", suggesting that women’s reproductive capacity declines after delivery and gradually reaches the level of first-time pregnant women, which could explain the relationship between long IPIs and adverse perinatal outcomes.The lack of an association observed between short IPIs after previous CS and adverse perinatal outcomes in our study may be attributed to the small proportion of women with short IPIs in our cohort. Two previous studies have examined the relationship between IPI after CS and abnormal placental position, and both studies reported no significant association 29,30 . Our investigation aligns with these previous studies, as we found no association between abnormal placental position and IPI in our cohort. A short IPI has been associated with an increased risk of inadequate healing of uterine scarring 3 1 .In contrast to previous findings, we did not observe a significant association between a short IPI and placenta previa or placenta accreta in our results. We hypothesize that the association observed between a long IPI and abnormal placental position may be attributed to physiological changes in the uterus that occur with AMA. Previous research has identified an increased occurrence of placenta previa among women with AMA and has suggested that compromised uteroplacental blood flow in older women may lead to a larger placenta encroaching on the cervical os, thus increasing the risk of placenta previa 32-34 .It is important to note that our study may be biased due to the small number of patients who became pregnant within one year of their previous CS, and none of these patients had an abnormal placental position. Our investigation found that IPI was not a risk factor for anemia and GDM. But a study conducted by Hanley et al. reported that women with a longer IPI were more likely to develop GDM 35 . It is important to note that their study used women with multiple pregnancies as the control group, and the correlation between IPI and GDM may have been influenced by maternal age, as maternal age tends to increase with longer IPIs. In our study, we did not find a significant difference in maternal age among the four groups, specifically those with an IPI of 120 months or longer. Being overweight has also been shown to be a risk factor for GDM 36 .Therefore, our findings suggest that IPI alone may not be a significant risk factor for anemia and GDM, independent of maternal age and BMI. Repeat CS is known to increase the risk of maternal complications 3 7 , TOLAC is an option for women with a scarred uterus and can potentially avoid surgery-related morbidities, benefiting subsequent pregnancies. Failed TOLAC is associated with an increased risk of uterine rupture and blood transfusion, which can be detrimental for both the mother and the fetus 3 8 ,3 9 . A systematic report showed that the median incidence of complete uterine rupture was 1% among women with previous CS 40 , but a wide range of incidences of incomplete uterine rupture was reported, from 2.1% to10.1% 4 1 ,4 2 . In our study, 0.84% (n = 5) of women were found to have incomplete uterine rupture during surgery, with no cases of complete uterine rupture reported. Previous studies have identified advanced maternal age, multiparity (≥ 6), extremely short IPI, vaginal delivery history, and macrosomia as risk factors for complete uterine rupture 6,4 3 -44 . After adjusting for potential confounders, we found that among women with a history of emergency CS, IPI was not associated with the occurrence of uterine rupture. In the group of women with a history of elective repeat CS, an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture. Nevertheless, this risk decreased for women conceiving in the IPI range of 60 to 119 months and 120 months or longer compared to an IPI of 24 to 59 months.It is worth noting that studies have reported a significantly increased risk of uterine rupture during emergency CS, while mothers who underwent elective repeat CS had a minimal risk of uterine rupture (ranging from 0% to 0.004%) 44 . This could indicate that the risk of uterine rupture is underestimated for elective repeat CS, potentially due to risk mitigation strategies employed during these surgeries. One strength of this study is its focus on the effects of extremely long IPI, which is relevant to China’s current birth policy. Our findings suggest that both shorter and longer IPIs are risk factors for subsequent pregnancies in women with a history of CS. In addition, our analysis of adverse pregnancy outcomes related to IPI was comprehensive, including scar-related morbidities and common pregnancy morbidities. However, there are limitations to consider. The retrospective design of our study prevented us from conducting a power analysis. The low incidence of TOLAC (3.2%) and the small number of uterine rupture cases may have resulted in an underestimation of the risks involved. We were unable to accurately analyse the effects of IPI on the success of VBAC or the risk of uterine rupture in the subset of women who underwent TOLAC. Another limitation is the small sample size, particularly in the analysis of short IPI. The conclusions regarding short IPI should be interpreted with caution. Considering that the WHO recommends an IPI of longer than 24 months, further exploration of the effects of short IPI would require a prospective study design. In our previous systematic evaluation, we found that an IPI longer than 6-8 months after CS can reduce the risk of adverse maternal and neonatal outcomes, which differs significantly from the results of this study. Therefore, further research is needed to clarify the optimal IPI for women with a history of CS, and prospective studies with larger sample sizes are necessary to identify suitable candidates for TOLAC and ensure their safety through intensive prenatal care. Conclusion In summary, our study found that an IPI of ≥120 months was associated with a higher risk of GHP in late pregnancy. Different IPIs after CS influenced the risk of incomplete uterine rupture, although this effect was not statistically significant after adjusting for other potential confounders. It is possible that IPI may interact with other factors to increase the risk of incomplete uterine rupture. Our findings emphasize the importance of obstetricians identifying pregnancies with an extremely long IPI after a previous CS and providing appropriate interventions to improve perinatal outcomes. Consideration of the optimal IPI should be given in family planning for a second baby. Abbreviations IPIs - interpregnancy intervals aOR - adjusted odds ratio CI – confidence interval WHO - World Health Organization CSs - caesarean sections AMA - advanced maternal age GDM - gestational diabetes mellitus GHP - gestational hypertension LBW - low birth weight NICU – neonatal intensive care unit VBAC - vaginal birth after caesarean section CD - caesarean delivery ISSHP - International Society of Study of Hypertension in Pregnancy IVF-ET - in vitro fertilization and embryo transfer PROM - premature rupture PPH - postpartum haemorrhage TOLAC - trial of labour after caesarean Declarations Funding The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Competing Interests The authors have no relevant financial or non-financial interests to disclose. . Author Contributions All authors contributed to the study conception and design. RZ contributed to the conception and design of the study, the interpretation of the data, and provided critical revisions to the article.SPZ and LD were involved in the execution of the study, the initial drafting of the manuscript, and provided critical revisions. QX and LY contributed to the interpretation of the data. QLW was responsible for the collection and analysis of the data. LY provided expertise in solving statistical issues and contributed to the revision of the article.All raw data generated or analysed during the course of this study can be obtained from the corresponding author upon reasonable request. Ethics approval This study was approved by the Ethics Committee of the West China Second University Hospital of Sichuan University (reference number: 2016(010)). Consent to participate All methods and procedures were conducted in strict accordance with the relevant guidelines and regulations. 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Gurol-Urganci I, Bou-Antoun S, Lim CP, Cromwell DA, Mahmood TA, Templeton A, et al(2013)Impact of Caesarean section on subsequent fertility: a systematic review and meta-analysis. Hum Reprod 28(7):1943-52. Fox NS, Gerber RS, Mourad M, Saltzman DH, Klauser CK, Gupta S, et al(2014)Pregnancy outcomes in patients with prior uterine rupture or dehiscence. Obstet Gynecol 123(4):785-9. Fitzpatrick KE, Kurinczuk JJ, Bhattacharya S, Quigley MA(2019) Planned mode of delivery after previous cesarean section and short-term maternal and perinatal outcomes: A population-based record linkage cohort study in Scotland. PLoS Med 16(9):e1002913. Hofmeyr GJ, Say L, Gülmezoglu AM(2005) WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture. BJOG 112(9):1221-8. Nielsen TF, Ljungblad U, Hagberg H(1989) Rupture and dehiscence of cesarean section scar during pregnancy and delivery. Am J Obstet Gynecol 160(3):569-73. Fogelberg M, Baranov A, Herbst A, Vikhareva O(2017) Underreporting of complete uterine rupture and uterine dehiscence in women with previous cesarean section. J Matern Fetal Neonatal Med.30(17):2058-61. Jastrow N, Roberge S, Gauthier RJ, Laroche L, Duperron L, Brassard N, et al(2010) Effect of birth weight on adverse obstetric outcomes in vaginal birth after cesarean delivery. Obstet Gynecol 115(2 Pt 1):338-43. Alcalay M, Hourvitz A, Reichman B, Luski A, Quint J, Barkai G, et al(1996) Prelabour rupture of membranes at term: early induction of labour versus expectant management. Eur J Obstet Gynecol Reprod Biol 70(2):129-33. Tables Table 1. Demographic and Clinical Characteristics in the Four Groups by Interpregnancy Interval. Characteristics Interpregnancy interval (mon) P value < 24 (n = 16) 24-59 (n = 89) 60-119 (n = 290) ≥ 120 (n = 196) Delivery age (y) 36.22±4.16 37.46±3.2 36.25±3.68 38.01±2.68 0.538 Education (y) < 0.001 ≤ 12 1 (6.25) 4 (4.49) 14 (4.84) 13 (6.67) 13-16 1 (6.25) 6 (6.74) 19 (6.57) 26 (13.33) 17-21 8 (50.00) 55 (61.80) 179 (61.94) 145 (74.35) ≥21 6 (37.50) 24 (26.97) 77 (26.65) 11 (5.64) BMI, No. (Kg/m 2 ) 0.567 28 1 (6.25) 5 (5.62) 7 (2.41) 7 (3.57) Number of previous pregnancies < 0.001 ≥ 3 11 (68.75) 64 (71.91) 217 (74.83) 172 (87.76) < 3 5 (31.25) 25 (28.09) 73 (25.17) 24 (12.24) Parity ≥ 2 6 (37.50) 9 (10.11) 17 (5.86) 9 (4.59) < 0.001 Prior cesareans ≥ 2 4 (25.00) 8 (8.99) 14 (4.83) 4 (2.04) < 0.001 Prior vaginal birth 0 (0.00) 0 (0.00) 4 (1.4) 2 (1.0) 0.692 IVF-ET 0 (0.00) 2 (2.25) 3 (1.03) 2 (1.02) 0.765 Preexisting hypertension 1(6.2) 0 (0.0) 0 (0.0) 3 (1.5) 0.107 Preexisting diabetes 0 (0.0) 1 (1.1) 2 (0.7) 2 (1.0) 0.946 Gestational age at delivery (weeks) 37.88±1.71 37.58±3.67 37.86±2.76 37.72±2.23 0.857 Mode of delivery 0.311 Repeated cesarean section 16 (100.00) 85 (95.51) 278 (95.86) 193 (98.47) Vaginal birth after CS 0 (0.00) 4 (4.49) 12 (4.14) 3 (1.53) Type of repeated cesarean section Emergency cesarean section 7 (43.7) 31 (34.8) 92 (31.7) 71 (36.2) 0.614 CS with indications 10 (62.5) 25 (28.1) 80 (27.6) 53 (27.0) 0.352 Data are expressed as mean ± SD, or n (%) with p-value from exact chi-square. BMI, body mass index; IVF-ET, in vitro fertilization and embryo transfer. Table 2. Rates of Maternal and Neonatal outcomes in the Four Groups by Interpregnancy Interval. Perinatal outcome Interpregnancy interval (mon) P value < 24 (n = 16) 24-59 (n = 89) 60-119 (n = 290) ≥ 120 (n = 196) Anemia 1 (6.3) 7 (7.9) 34 (11.7) 24 (12.2) 0.641 GHP 4 (2.5) 3 (4.5) 7 (2.4) 12 (6.1) < 0.001 GDM 0.176 Grade A1 11 (68.8) 59 (66.3) 210 (72.4) 123 (62.8) Grade A2 4 (25.0) 27 (30.3) 67 (23.1) 67 (34.2) Placenta inherence 0 6 (6.7) 24 (8.3) 19 (9.7) 0.525 Placental position 0.255 Normal 13 (81.2) 81 (91.0) 266 (91.7) 165 (84.2) Low placenta 1 (6.3) 3 (3.4) 10 (3.4) 14 (7.1) Partial or marginal placenta previa 2 (12.5) 3 (3.4) 2 (0.7) 6 (3.1) Complete placenta previa 0 (0.0) 2 (2.2) 12 (4.2) 11 (5.6) Pernicious placenta 1 (6.3) 3 (3.4) 18 (6.2) 9 (4.6) 0.713 placenta accreta 0 6 (6.7) 24 (8.3) 19 (9.7) 0.525 PROM 2 (12.5) 12 (13.5) 39 (13.4) 39 (19.9) 0.241 Incomplete Uterine rupture 0 (0.0) 1 (1.1) 2 (0.7) 2 (1.0) 0.946 placental abruption 0 (0.0) 0 (0.0) 3 (1.0) 1 (0.5) 0.718 Postpartum hemorrhage 0 (0.0) 0 (0.0) 2 (0.7) 2 (1.0) 0.787 Hysterectomy 1 (6.3) 5 (5.6) 6 (2.1) 3 (1.5) 0.147 Preterm birth 4 (25.0) 11 (12.4) 38 (13.1) 30 (15.3) 0.518 Preterm birth < 34 weeks 0 (0.0) 5 (5.6) 10 (3.4) 12 (6.1) 0.406 Birth weight (g) 3197±576 3211±649 3265±647 3188±531 0.566 Birth length (cm) 48.81±2.07 48.91±3.32 48.88±4.17 48.83±2.61 0.998 LBW 2 (12.5) 8 (8.9) 23 (7.9) 22 (11.2) 0.635 1-min Apgar score <10 0 (0.0) 5 (5.6) 11 (3.8) 9 (4.6) 0.722 NICU admission 2 (12.5) 9 (10.1) 35 (12.1) 22 (11.2) 0.994 Data are expressed as mean ± SD, or n (%) with p-value from exact chi-square.GDM, gestational diabetes mellitus; GHP, gestational hypertension; PROM, premature rupture of membrane. LBW, the birth weight of newborns is less than 2500g; NICU, neonatal intensive care. Table 3. Association of Anemia, GHP, GDM and IPI in the Three Groups with IPI of <24 months, 60-119 months and ≥ 120 months. Outcomes Interpregnancy interval (mon) * < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) P value aOR (95% CI) P value aOR (95% CI) P value Anemia 1.324(0.14-12.46) 0.796 0.648(0.27-1.53) 0.323 0.703(0.28-1.75) 0.449 GHP 0.688(0.17-2.77) 0.598 0.932(0.43-5.20) 0.472 16.223(2.73-96.33) 0.002 GDM 1.043(0.31-3.51) 0.946 0.715(0.42-1.21) 0.213 0.902(0.52-1.58) 0.717 IPI, interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; GHP, gestational hypertension; GDM, gestational diabetes mellitus. Adjusted for education status, gravidity, parity, number of previous cesarean section. Table 4. Association of other Perinatal Outcomes and IPI in the Three Groups with IPI of <24 months, 60-119 months and ≥ 120 months (without adjusting for any confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 39.02 2.337 (0.55-9.97) 0.914(0.40-2.11) 1.902(0.84-4.33) 0.271 Pernicious placenta with or without placenta accreta 32.644 0.52(0.05-5.37) 0.53 (0.15-1.83) 0.73(019-2.74) 0.765 PROM 35.875 0.92(0.19-4.55) 1.097(0.50-2.70) 1.59(0.79-3.22) 0.181 Incomplete Uterine rupture 19.821 1.89(1.13-1.87) 0.61(0.05-6.82) 0.91(0.08-10.14) 0.002 Postpartum hemorrhage 0.001 0.85(0.63-1.48) 2.48(0.76-8.25) 3.69(0.68-12.68) 0.997 Hysterectomy 0.068 0.74(0.62-1.38) 1.18(0.74-1.68) 1.27(0.52-3.28) 0.564 1-min Apgar score <10 37.565 1.55(0.45-4.63) 0.62(0.33-1.85) 0.68(0.12-3.21) 0.007 NICU admission 38.616 1.27(0.25-6.51) 1.22(0.56-2.65) 1.124(0.49-2.55) 0.356 IPI,interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Table 5. Association of other Perinatal Outcomes and IPI in the Three Groups with IPI of <24 months, 60-119 months and ≥ 120 months (with adjusting for some confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 12.971 1.72(0.37-8.11) 0.862(0.36-2.05) 1.885(0.79-4.49) 0.286 Pernicious placenta with or without placenta accreta 10.848 1.68(0.15-18.65) 2.134(0.58-7.85) 1.19(0.29-4.96) 0.318 PROM 0.934 0.77(0.14-4.27) 1.06(0.50-2.25) 1.56(0.72-3.41) 0.334 Incomplete Uterine rupture 0.001 1.07(0.96-1.53) 0.55 (0.046-6.49) 0.57 (0.05-6.83) 0.991 Postpartum hemorrhage 0.002 0.43(0.23-6.42) 1.54(0.87-5.43) 1.91(0.75-7.59) 0.994 Hysterectomy 0.163 0.78(0.56-4.41) 1.41(0.78-3.52) 1.63(0.57-3.68) 0.612 1-min Apgar score <10 1.588 1.84(0.40-3.83) 0.69(0.22-2.17) 0.55(0.15-1.93) 0.208 NICU admission 5.572 1.403(0.27-7.40) 1.293(0.59-2.84) 1.071(0.46-2.51) 0.184 IPI,interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Aadjusted for education status, gravidity, parity, number of previous cesarean section. Table 6. Association of IPI and other Perinatal Outcomes in Emergency Cesarean Section (without adjusting for any confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 13.379 4.83(0.56-41.41) 0.82(0.15-4.48) 2.38(0.49-11.55) 0.381 Pernicious placenta with or without placenta accreta 11.195 0.23(0.01-4.20) 0.74(0.08-6.90) 0.44(0.05-3.93) 0.526 PROM 8.228 0.88(0.14-5.34) 0.68(0.26-1.75) 0.38(0.14-0.99) 0.822 Incomplete Uterine rupture 0.002 1.38(0.84-1.95) 0.68(0.47-1.16) 0.51(0.23-1.22) 0.997 Postpartum hemorrhage 0.225 0.91(0.37-1.47) 1.34(0.63-2.24) 1.64(0.43-4.67) 0.43 Hysterectomy 0.285 0.67(0.36-1.45) 1.25(0.7-2.36) 1.83(0.74-4.96) 0.283 1-min Apgar score <10 13.52 1.65(0.5-6.42) 0.76(0.18-3.14) 0.86(0.20-3.69) 0.287 NICU admission 0.045 0.87(0.59-1.45) 1.14(0.64-1.56) 1.17(0.45-2.21) 0.748 IPI, interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Table 7. Association of IPI and other Perinatal Outcomes in Emergency Cesarean Section (with adjusting for some confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 0.005 3.95(0.39-39.91) 0.72(0.13-4.12) 2.3(0.41-13.10) 0.996 Pernicious placenta with or without placenta accreta 0.001 3.97(0.15-108.27) 0.15(0.11-14.41) 1.82(0.14-23.97) 0.997 PROM 0.493 1.13(0.18-7.24) 1.53(0.58-4.05) 2.6(0.94-7.20) 0.48 Incomplete Uterine rupture 0.057 1.27(0.74-1.83) 0.96(0.71-1.39) 0.83(0.48-1.62) 0.993 Postpartum hemorrhage 0.185 0.72 (0.34-1.69) 1.11(0.57-2.47) 1.58(0.35-5.64) 0.538 Hysterectomy 0.122 0.73(0.37-1.72) 1.31(0.81-2.54) 1.57(0.6-4.76) 0.464 1-min Apgar score <10 0.006 1.67(0.57-8.51) 0.94(0.17-4.06) 0.68(0.12-3.86) 0.937 NICU admission 0.331 0.83(0.59-1.26) 1.48(0.84-2.44) 1.85(0.99-4.37) 0.112 IPI, interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Adjusted for education status, gravidity, parity, number of previous cesarean section. Table 8. Association of IPI and other Perinatal Outcomes in Selective Cesarean Section (without adjusting for any confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 23.062 1.14(0.12-10.96) 0.91(0.34-2.41) 1.66(0.63-4.39) 0.348 Pernicious placenta with or without placenta accreta 20.44 0.86(0.44-1.76) 2.12(0.47-9.62) 0.88(0.16-4.96) 0.211 PROM 23.627 1.97(0.58-10.2) 0.64(0.21-2.15) 0.76(0.21-2.72) 0.015 Incomplete Uterine rupture 15.471 1.25(0.81-8.92) 0.29(0.02-4.66) 0.44 (0.03-7.14） 0.028 Postpartum hemorrhage 0.001 0.89(0.62-1.45) 1.11(0.84-1.58) 1.12(0.65-2.31) 0.996 Hysterectomy 1.334 1.21 (0.66-1.44) 0.89(0.64-1.81) 0.78(0.65-1.92) 0.813 1-min Apgar score <10 20.444 1.31(0.55-2.95) 0.57(0.10-3.21) 0.66(0.11-4.04) 0.082 NICU admission 0.228 1.13(0.35-4.84) 0.87(0.13-3.83) 0.84(0.07-3.44) 0.727 IPI, interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Table 9. Association of IPI and other Perinatal Outcomes in Selective Cesarean Section (with adjusting for some confounding factors). Perinatal outcomes index Interpregnancy interval (mon) * P value < 24 (n = 121) 60-119 (n = 712) ≥ 120 (n = 246) aOR (95% CI) aOR (95% CI) aOR (95% CI) Abnormal placental position 9.27 0.39(0.03-5.08) 0.91(0.32-2.56) 1.98(0.69-5.68) 0.249 Pernicious placenta with or without placenta accreta 6.17 0.8(0.46-1.71) 2.32(0.47-11.51) 0.601(0.08-4.22) 0.131 PROM 0.421 0.86(0.46-1.51) 1.14(0.72-1.42) 1.28(0.6-1.84) 0.637 Incomplete Uterine rupture 0.006 1.59(0.83-2.39) 0.24(0.01-4.22) 0.23(0.01-4.39) 0.996 Postpartum hemorrhage 0.155 0.26(0.09-1.46) 1.57(0.81-1.96) 1.76(0.45-3.84) 0.995 Hysterectomy 0.314 0.77(0.52-2.21) 1.25(0.73-1.81) 1.42(0.45-2.68) 0.508 1-min Apgar score <10 3.125 1.23(0.51-3.44) 0.98(0.2-2.93) 0.88(0.22-5.99) 0.711 NICU admission 1.259 1.34(0.37-7.77) 0.67(0.24-3.82) 0.49(0.15-1.37) 0.814 IPI, interpregnancy interval. * , using IPI of 24-59 months as reference category. aOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane. Abnormal placental position, including low placenta, partial and complete placenta previa. Adjusted for education status, gravidity, parity, number of previous cesarean section. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4089431","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":279234023,"identity":"f0385495-3fa1-4169-b067-d0283da3902e","order_by":0,"name":"shengping zhou","email":"","orcid":"https://orcid.org/0009-0001-4772-2823","institution":"Sichuan University WCSUH: Sichuan University West China Second University Hospital","correspondingAuthor":false,"prefix":"","firstName":"shengping","middleName":"","lastName":"zhou","suffix":""},{"id":279234024,"identity":"30c4b765-3a22-4649-9e2b-083da2a933ae","order_by":1,"name":"li dai","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"li","middleName":"","lastName":"dai","suffix":""},{"id":279234025,"identity":"52a961d3-3862-48f8-a070-f48a2d8459a9","order_by":2,"name":"Qin Xu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Qin","middleName":"","lastName":"Xu","suffix":""},{"id":279234026,"identity":"e876ac5f-d294-42bc-8a9b-5ea4d4afb94d","order_by":3,"name":"Lei Ye","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Lei","middleName":"","lastName":"Ye","suffix":""},{"id":279234027,"identity":"569e0279-2a48-4ba7-b288-3980361cc520","order_by":4,"name":"qilin wang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"qilin","middleName":"","lastName":"wang","suffix":""},{"id":279234028,"identity":"a1e6a0bc-2a77-4adc-8891-d73b1cacf805","order_by":5,"name":"Rong Zhou","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYDACCQSD8QGElUC8FmYDkrWwSRClRX528zHpioo7dg3SPWaVP2oOM/Cz5xgw/NyBWwvjnGNpkmfOPEtukDmWdpvn2GEGyZ43Boy9Z3BrYZbIMZNsbDuczCCRfOw2Y8NhBoMbOQbMjG24tbAhtCS2Ff4EarEnpIUHqsUOZAsDL8gWCQJaJCTSki0bzhxOYAAypHmOpfNInHlWcLAXjxb5GckHbzZUHLZnkMgx/PijxlqOvz1544OfeLTAQOL+A1CXgogDhDUwMNgTo2gUjIJRMApGKAAA4QJK/FVgRG0AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-4540-7336","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Rong","middleName":"","lastName":"Zhou","suffix":""}],"badges":[],"createdAt":"2024-03-13 05:34:52","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4089431/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4089431/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":52789888,"identity":"9a86d71f-7321-4eb1-9a80-c33c7ecf4098","added_by":"auto","created_at":"2024-03-15 19:48:00","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":38233,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFlowchart of sample selection and statistics collection\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4089431/v1/acdfef68f397475b4653bd7c.png"},{"id":56892603,"identity":"ffb5c44c-8194-4b06-aa3c-e9f4bc5a9314","added_by":"auto","created_at":"2024-05-21 20:22:24","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1199922,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4089431/v1/b691ac94-0e65-4c97-bc53-3f413991373e.pdf"}],"financialInterests":"","formattedTitle":"Impact of Interpregnancy Interval after Caesarean Section on Perinatal Outcomes in Multiparous Women of Advanced Maternal Age: A Retrospective Cohort Study","fulltext":[{"header":"Background","content":"\u003cp\u003eAccording to the recommendations of the World Health Organization (WHO), it is advised to wait at least two years between a previous live birth and the subsequent conception, regardless of the mode of delivery\u003csup\u003e1\u003c/sup\u003e. In 2016,\u0026nbsp;the implementation of\u0026nbsp;Chinese\u0026nbsp;revised two-child\u0026nbsp;policy has led to a significant increase in the number of multiparous women\u0026nbsp;\u003csup\u003e2\u003c/sup\u003e .This has also highlighted the emerging issue of scar uterus re-pregnancy and associated delivery complications resulting from\u0026nbsp;Chinese\u0026nbsp;high rate of caesarean sections（CSs）\u003csup\u003e3\u003c/sup\u003e.\u0026nbsp;An increasing number of families, who had chosen\u0026nbsp;CS\u0026nbsp;for their first child, are now confronted with the choice of having a second child. As a result, managing a growing number of high-risk parturients with multiple risk factors, including\u0026nbsp;advanced maternal age(AMA), long IPI, and previous CS, has become challenging for obstetricians in China. These risk factors have been shown to increase the likelihood of adverse pregnancy outcomes, such as\u0026nbsp;placenta previa\u003csup\u003e4\u003c/sup\u003e,uterine rupture\u003csup\u003e5,6\u003c/sup\u003e ,gestational hypertension (GHP)\u003csup\u003e7,8\u003c/sup\u003e ,gestational diabetes mellitus (GDM), preterm delivery, low birth weight (LBW), and neonatal intensive care unit (NICU) admission\u003csup\u003e2,9\u003c/sup\u003e\u003csup\u003e-14\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eIn our previous systematic review, we examined the relationship between IPI and adverse pregnancy outcomes in women who had previously undergone a CS. We observed associations between IPI and risks of uterine rupture, success of vaginal birth after CS (VBAC), and placenta previa\u003csup\u003e15\u003c/sup\u003e. Due to variations in the measurement and categorization of birth spacing in previous studies, we were unable to determine the optimal IPI after CS. Furthermore, the implementation of the two-child policy in China following the 36-year-long one-child policy has led to a significant increase in the number of pregnant women with long IPIs. Given the unique circumstances related to family planning policies and diverse patterns of pregnancies and deliveries in China, it was necessary to conduct a specific study on Chinese women. To address this gap, we conducted a large retrospective cohort study to investigate the association between IPI after previous CS and adverse pregnancy outcomes.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective cohort study was conducted at West China Second University Hospital, Sichuan University, which is a tertiary care hospital. The study specifically targeted older women(defined as being 35 years or older at the time of delivery)\u0026nbsp;with a history of CS who gave birth at our hospital between January\u0026nbsp;2016\u0026nbsp;and December\u0026nbsp;2016. Data for the study were collected from the electronic medical system and supplemented with information from medical records. Two trained abstractors were assigned to review the abstract data obtained from the medical charts. The study received ethical approval from the Ethics Committee and Data Inspectorate of West China Second University Hospital, Sichuan University (No.\u0026nbsp;2016(010)).\u003c/p\u003e\n\u003cp\u003eOur primary analysis included all women with a history of at least one previous caesarean delivery (CD) who gave birth between 28 and less than 42 weeks of gestation. We excluded women who met the following criteria: (1) had undergone uterine surgery other than caesarean section, (2) did not receive routine antenatal care, (3) had multiple pregnancies, and (4) had fetal malformations.\u003c/p\u003e\n\u003cp\u003eIPI in this study was defined as the duration between the date of the last caesarean section and the conception date of the subsequent delivery. The IPI was estimated by subtracting the gestational age at birth from the delivery date of the index pregnancy. For the purpose of analysis, the IPI was categorized into four groups: less than 24 months, 24-59 months, 60-119 months, and 120 months or greater.\u003c/p\u003e\n\u003cp\u003eMaternal outcomes assessed in this study included anaemia in late pregnancy (defined as a haemoglobin concentration below 110 g/L between 32 and 42 weeks of gestation)\u003csup\u003e16\u003c/sup\u003e,GHP\u0026nbsp;(in accordance with the consensus statement from the International Society of Study of Hypertension in Pregnancy（ISSHP）)\u0026nbsp;\u003csup\u003e17\u003c/sup\u003e,GDM categorized as Grade A1 (indicating well-controlled blood glucose through non-drug therapy) or Grade A2 (indicating the need for medically controlled blood glucose as per WHO criteria)\u003csup\u003e18\u003c/sup\u003e, abnormal placental position, pernicious placenta, placenta accreta, placental abruption, \u003ca href=\"javascript%3A;\"\u003epremature rupture\u0026ensp;\u003c/a\u003e(PROM), uterine rupture (classified as incomplete or complete rupture detected during caesarean section by experienced obstetricians)\u003csup\u003e19\u003c/sup\u003e ,postpartum haemorrhage (PPH), and hysterectomy. Adverse fetal outcomes assessed included preterm birth, admission to the NICU, low 1-minute Apgar score (defined as an Apgar score less than 10 evaluated 1 minute after birth by a professional obstetrician), and LBW(\u0026nbsp;defined as a birth weight less than 2500 g).\u003c/p\u003e\n\u003cp\u003eTo account for potential confounding variables, such as demographic and clinical characteristics that may vary among the four IPI groups and influence the association between IPI and perinatal outcomes, multivariable logistic regression analysis models were developed. These models were used to adjust for the impact of IPI following a\u0026nbsp;CS\u0026nbsp;on adverse maternal and fetal outcomes. Additionally, since previous research has indicated that emergency\u0026nbsp;CS\u0026nbsp;significantly increases the risk of adverse perinatal outcomes\u003csup\u003e20\u003c/sup\u003e ,multivariate logistic regression models were established to analyse the relationship between IPI and perinatal outcomes separately for emergency and elective\u0026nbsp;CS\u0026nbsp;cases. Sociodemographic characteristics and adverse pregnancy outcomes were compared among the four IPI groups using the chi-square test for categorical variables and conducting a one-way analysis of variance for continuous variables. Multivariable logistic regression analysis was then performed for each pregnancy outcome to examine the association between different IPIs while controlling for known and suspected confounding factors. An IPI of 24-59 months was used as the reference category, following the guidelines of the WHO\u003csup\u003e1\u003c/sup\u003e. Data analysis was conducted using SPSS Statistics version 21.0 for Windows (SPSS Inc., Chicago, IL, USA). A significance level of p\u0026lt;0.05 (two-tailed) was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 655 deliveries by women with advanced maternal age and a history of\u0026nbsp;CS\u0026nbsp;were documented at the West China Second University Hospital between January 1,\u0026nbsp;2016, and December 31,\u0026nbsp;2016. After applying the exclusion criteria, 64 women were excluded: 17 due to lack of routine antenatal care, 28 due to multiple pregnancies, 13 due to fetal malformation, and 6 due to uterine surgery other than\u0026nbsp;CS. The final sample size for this retrospective cohort study included 591 women, who were then categorized into four groups based on different IPIs: 16 women with an IPI of less than 24 months, 89 women with an IPI of 24-59 months, 290 women with an IPI of 60-119 months, and 196 women with an IPI of 120 months or longer (Figure 1).\u003c/p\u003e\n\u003cp\u003eThe average age at delivery for all cohorts was 36.8 years, and there were no significant differences among the four groups (Table 1). However, women with an IPI\u0026nbsp;of 120 months or more had a higher prevalence of gravidity (number of pregnancies) of three or more compared to the other three groups. Additionally, this group had a lower prevalence of parity (number of live births) of two or more and a lower prevalence of prior CS of two or more with indications. There were also significant differences among the four groups in terms of educational status distribution (p \u0026lt; 0.001). Women with an IPI of less than 24 months had a history of two or more CS compared to the other three groups (p \u0026lt; 0.001). There were no significant differences in maternal body mass index (BMI), history of vaginal delivery, use of in vitro fertilization and embryo transfer (IVF-ET), presence of chronic hypertension or pregestational diabetes mellitus (PGDM), and gestational age at delivery among the four groups. Only 3.2% (n = 19) of the women achieved a VBAC, and the rates of emergency CS and CS with indications did not differ among the four groups.\u003c/p\u003e\n\u003cp\u003eWomen with an IPI of 120 months or longer had a higher rate of GHP compared to the other three groups (6.1%, p \u0026lt; 0.001). However, no significant differences were found among the four groups in terms of other maternal outcomes, such as anaemia, GDM, low placenta, placenta previa, pernicious placenta, placenta accreta, placental abruption, PROM, PPH, and hysterectomy. Similarly, no significant differences were observed among the four groups in terms of perinatal outcomes, including preterm birth, delivery before 34 weeks of gestation, birth weight, birth length, low 1-minute Apgar score, LBW, or admission to the\u0026nbsp;NICU (Table 2).\u003c/p\u003e\n\u003cp\u003eMultivariate logistic analysis was conducted using an IPI of 24-59 months as the reference category to examine the associations between different IPIs and adverse perinatal outcomes. Results from Table 3 indicate that an IPI of 120 months or longer was associated with an increased risk of developing GHP in late pregnancy (adjusted odds ratio (aOR)\u0026nbsp;16.223, 95%\u0026nbsp;CI\u0026nbsp;2.73-96.33, p=0.002). On the other hand, an IPI of less than 24 months or 60-119 months was associated with a decreased risk of GHP in the third trimester (IPI of less than 24 months,\u0026nbsp;aOR 0.688, 95% CI 0.17-2.77, p=0.598; IPI of 60-119 months, aOR 0.932, 95% CI 0.43-5.20, p=0.472).\u0026nbsp;An IPI of less than 24, 60-119, or 120 months did not have a significant effect on the risk of developing anaemia and GDM.\u003c/p\u003e\n\u003cp\u003eResults from the analysis revealed that an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture (OR1.89, 95% CI 1.13-1.87). On the other hand, an IPI of 60-119 months (OR 0.61, 95% CI 0.05-6.82) and 120 months or longer (OR 0.91, 95% CI 0.08-10.14) significantly reduced the risk of incomplete uterine rupture. Additionally, an IPI of less than 24 months significantly increased the risk of low 1-minute Apgar scores (Table 4).\u0026nbsp;After adjusting for educational status, number of previous pregnancies, parity, and prior caesarean section, the results suggested that IPI was not a risk factor for incomplete uterine rupture (Table 5). Regardless of whether confounders were adjusted, IPI did not have an impact on other adverse perinatal outcomes, such as pernicious placenta, abnormal placental position, PROM,\u0026nbsp;PPH, hysterectomy, and admission to the NICU.\u003c/p\u003e\n\u003cp\u003eSeveral studies have shown that emergency\u0026nbsp;CS\u0026nbsp;can increase the risk of adverse perinatal outcomes\u003csup\u003e21\u003c/sup\u003e. In this study, we conducted a multivariable logistic regression analysis to examine the relationship between IPI and perinatal outcomes among 201 women with a history of emergency CS and 168 women with selective CS. The analysis revealed that IPI in women with a history of emergency CS was not significantly associated with the occurrence of uterine rupture (p \u0026gt; 0.05) (Table 6; Table 7). In women with a history of CS, IPI was found to be a risk factor for incomplete uterine rupture (p=0.028) and PROM (p = 0.015). Specifically, an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture (OR 1.25, 95% CI 0.81-8.92), while an IPI of 60-119 months (OR 0.29, 95% CI 0.02-4.66) and 120 months or longer (OR 0.44, 95% CI 0.03-7.14) significantly reduced the risk of incomplete uterine rupture. An IPI of less than 24 months was associated with an increased risk of PROM (OR 1.97, 95% CI 0.58-10.2), while an IPI of 60-119 months (OR 0.64, 95% CI 0.21-2.15) and 120 months or longer (OR 0.76, 95% CI 0.21-2.72) significantly reduced the risk of PROM. After adjusting for confounders such as educational status, number of previous pregnancies, parity, and prior CS, the IPI in women with a history of selective CS was not found to be a significant risk factor for incomplete uterine rupture (p = 0.996) and PROM (p = 0.637) (Tables 8 and 9).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn our study, we found that\u0026nbsp;IPI had an impact on adverse pregnancy outcomes in patients with\u0026nbsp;GHP during late pregnancy.\u0026nbsp;We did not observe any significant effects of IPI (less than 24 months, 60-119 months, or 120 months or longer) on the risk of developing anaemia and GDM.\u0026nbsp;There were no significant differences among the four groups when it came to perinatal outcomes such as preterm birth, delivery before 34 weeks of gestation, birth weight, birth length, low 1-minute Apgar score, LBW, or admission to the NICU. The rate of trial of labour after caesarean (TOLAC) was 3.2% (n = 19).\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;birth spacing\u0026nbsp;may have an impact on perinatal outcomes due to its potential effects on maternal health and nutrient concentrations.\u0026nbsp;The recovery period following a CS is typically longer compared to vaginal delivery. Previous studies have shown that for mothers aged 35 years or older, longer IPIs (60 months) were associated with an increased risk of preeclampsia compared to intervals of 18 months\u003csup\u003e22,23\u003c/sup\u003e. Other research has found that IPIs less than 6 months, 6-11 months, and 12-17 months were significantly protective against GDM, GHP, and maternal morbidity compared to an interval of 18-23 months\u003csup\u003e24\u003c/sup\u003e.In our study, we found that an IPI of 120 months or longer increased the risk of GHP in late pregnancy. This association may be attributed to the fact that pregnant women with longer IPIs tend to be older, which is a known risk factor for adverse pregnancy outcomes\u003csup\u003e25\u003c/sup\u003e .It has been reported that the association between IPI and adverse outcomes disappears when common confounders are taken into account.In our study, we did not find an association between an IPI of less than 24 months and an increased risk of adverse neonatal outcomes, such as preterm birth, low 1-minute Apgar score, LBW, and admission to the NICU.\u003c/p\u003e\n\u003cp\u003eSeveral studies have reported on the association between birth spacing and adverse neonatal outcomes\u003csup\u003e26\u003c/sup\u003e, but there has been limited research specifically focusing on women with a history of CS. A meta-analysis conducted in 2006 among multiparous women found that an IPI\u0026nbsp;shorter than 18 months and longer than 60 months had the highest risk for preterm birth and LBW\u003csup\u003e26\u003c/sup\u003e .Moreover, Class et al. conducted a study using cousin and sibling comparisons, which demonstrated that an IPI of 60 months or more was associated with increased risks for preterm delivery (before 37 weeks) and LBW\u003csup\u003e27\u003c/sup\u003e.Given the substantial increase in women with extremely long IPIs following the revised reproductive policy in China, in our study, we specifically analysed the association between adverse perinatal outcomes and an IPI of 120 months or longer, which was not explored in non-Chinese research. Zhu et al.\u003csup\u003e28\u003c/sup\u003e proposed the concept of \u0026quot;physiological regression\u0026quot;, suggesting that women\u0026rsquo;s reproductive capacity declines after delivery and gradually reaches the level of first-time pregnant women, which could explain the relationship between long IPIs and adverse perinatal outcomes.The lack of an association observed between short IPIs after previous CS and adverse perinatal outcomes in our study may be attributed to the small proportion of women with short IPIs in our cohort.\u003c/p\u003e\n\u003cp\u003eTwo previous studies have examined the relationship between IPI after CS and abnormal placental position, and both studies reported no significant association\u003csup\u003e29,30\u003c/sup\u003e. Our investigation aligns with these previous studies, as we found no association between abnormal placental position and IPI in our cohort. A short IPI has been associated with an increased risk of inadequate healing of uterine scarring\u003csup\u003e3\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e.In contrast to previous findings, we did not observe a significant association between a short IPI and placenta previa or placenta accreta in our results. We hypothesize that the association observed between a long IPI and abnormal placental position may be attributed to physiological changes in the uterus that occur with AMA. Previous research has identified an increased occurrence of placenta previa among women with AMA and has suggested that compromised uteroplacental blood flow in older women may lead to a larger placenta encroaching on the cervical os, thus increasing the risk of placenta previa\u003csup\u003e32-34\u003c/sup\u003e.It is important to note that our study may be biased due to the small number of patients who became pregnant within one year of their previous CS, and none of these patients had an abnormal placental position.\u003c/p\u003e\n\u003cp\u003eOur investigation found that IPI was not a risk factor for anemia and GDM.\u0026nbsp;But a\u0026nbsp;study conducted by Hanley et al. reported that women with a longer IPI were more likely to develop GDM\u003csup\u003e35\u003c/sup\u003e. It is important to note that their study used women with multiple pregnancies as the control group, and the correlation between IPI and GDM may have been influenced by maternal age, as maternal age tends to increase with longer IPIs. In our study, we did not find a significant difference in maternal age among the four groups, specifically those with an IPI of 120 months or longer. Being overweight has also been shown to be a risk factor for GDM\u003csup\u003e36\u003c/sup\u003e.Therefore, our findings suggest that IPI alone may not be a significant risk factor for anemia and GDM, independent of maternal age and BMI.\u003c/p\u003e\n\u003cp\u003eRepeat CS is known to increase the risk of maternal complications\u003csup\u003e3\u003c/sup\u003e\u003csup\u003e7\u003c/sup\u003e,\u0026nbsp;TOLAC\u0026nbsp;is an option for women with a scarred uterus and can potentially avoid surgery-related morbidities, benefiting subsequent pregnancies.\u0026nbsp;Failed TOLAC is associated with an increased risk of uterine rupture and blood transfusion, which can be detrimental for both the mother and the fetus\u003csup\u003e3\u003c/sup\u003e\u003csup\u003e8\u003c/sup\u003e\u003csup\u003e,3\u003c/sup\u003e\u003csup\u003e9\u003c/sup\u003e. \u0026nbsp;A systematic report showed that the median incidence of complete uterine rupture was 1% among women with previous CS\u003csup\u003e40\u003c/sup\u003e, but a wide range of incidences of incomplete uterine rupture was reported, from 2.1% to10.1%\u003csup\u003e4\u003c/sup\u003e\u003csup\u003e1\u003c/sup\u003e\u003csup\u003e,4\u003c/sup\u003e\u003csup\u003e2\u003c/sup\u003e. In our study, 0.84% (n = 5) of women were found to have incomplete uterine rupture during surgery, with no cases of complete uterine rupture reported. Previous studies have identified advanced maternal age, multiparity (\u0026ge; 6), extremely short IPI, vaginal delivery history, and macrosomia as risk factors for complete uterine rupture \u003csup\u003e6,4\u003c/sup\u003e\u003csup\u003e3\u003c/sup\u003e\u003csup\u003e-44\u003c/sup\u003e. After adjusting for potential confounders, we found that among women with a history of emergency CS, IPI was not associated with the occurrence of uterine rupture. In the group of women with a history of elective repeat CS, an IPI of less than 24 months significantly increased the risk of incomplete uterine rupture. Nevertheless, this risk decreased for women conceiving in the IPI range of 60 to 119 months and 120 months or longer compared to an IPI of 24 to 59 months.It is worth noting that studies have reported a significantly increased risk of uterine rupture during emergency CS, while mothers who underwent elective repeat CS had a minimal risk of uterine rupture (ranging from 0% to 0.004%)\u003csup\u003e44\u003c/sup\u003e. This could indicate that the risk of uterine rupture is underestimated for elective repeat CS, potentially due to risk mitigation strategies employed during these surgeries.\u003c/p\u003e\n\u003cp\u003eOne strength of this study is its focus on the effects of extremely long IPI, which is relevant to China\u0026rsquo;s current birth policy. Our findings suggest that both shorter and longer IPIs are risk factors for subsequent pregnancies in women with a history of CS. In addition, our analysis of adverse pregnancy outcomes related to IPI was comprehensive, including scar-related morbidities and common pregnancy morbidities. However, there are limitations to consider. The retrospective design of our study prevented us from conducting a power analysis. The low incidence of TOLAC (3.2%) and the small number of uterine rupture cases may have resulted in an underestimation of the risks involved. We were unable to accurately analyse the effects of IPI on the success of VBAC or the risk of uterine rupture in the subset of women who underwent TOLAC. Another limitation is the small sample size, particularly in the analysis of short IPI. The conclusions regarding short IPI should be interpreted with caution. Considering that the WHO recommends an IPI of longer than 24 months, further exploration of the effects of short IPI would require a prospective study design. In our previous systematic evaluation, we found that an IPI longer than 6-8 months after CS can reduce the risk of adverse maternal and neonatal outcomes, which differs significantly from the results of this study. Therefore, further research is needed to clarify the optimal IPI for women with a history of CS, and prospective studies with larger sample sizes are necessary to identify suitable candidates for TOLAC and ensure their safety through intensive prenatal care.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, our study found that an IPI of \u0026ge;120 months was associated with a higher risk of GHP in late pregnancy. Different IPIs after CS influenced the risk of incomplete uterine rupture, although this effect was not statistically significant after adjusting for other potential confounders. It is possible that IPI may interact with other factors to increase the risk of incomplete uterine rupture. Our findings emphasize the importance of obstetricians identifying pregnancies with an extremely long IPI after a previous CS and providing appropriate interventions to improve perinatal outcomes. Consideration of the optimal IPI should be given in family planning for a second baby.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003e\u003cstrong\u003eIPIs\u003c/strong\u003e-\u0026nbsp;interpregnancy intervals\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eaOR\u003c/strong\u003e- adjusted odds ratio\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCI\u003c/strong\u003e \u0026ndash; confidence interval\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eWHO\u003c/strong\u003e-\u0026nbsp;World Health Organization\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCSs\u003c/strong\u003e-\u0026nbsp;caesarean sections\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAMA\u0026nbsp;\u003c/strong\u003e- advanced maternal age\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGDM\u0026nbsp;\u003c/strong\u003e- gestational diabetes mellitus\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGHP\u0026nbsp;\u003c/strong\u003e- gestational hypertension\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLBW\u003c/strong\u003e - low birth weight\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNICU\u003c/strong\u003e \u0026ndash; neonatal intensive care unit\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eVBAC\u0026nbsp;\u003c/strong\u003e- vaginal birth after caesarean section\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCD\u0026nbsp;\u003c/strong\u003e- caesarean delivery\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eISSHP\u0026nbsp;\u003c/strong\u003e- International Society of Study of Hypertension in Pregnancy\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIVF-ET\u003c/strong\u003e - in vitro fertilization and embryo transfer\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePROM\u003c/strong\u003e-\u0026nbsp;premature rupture\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePPH\u003c/strong\u003e - postpartum haemorrhage\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTOLAC\u003c/strong\u003e - trial of labour after caesarean\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch3\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/em\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAll authors contributed to the study conception and design.\u003c/em\u003eRZ contributed to the conception and design of the study, the interpretation of the data, and provided critical revisions to the article.SPZ and LD\u0026nbsp;were involved in the execution of the study, the initial drafting of the manuscript, and provided critical revisions. QX and LY contributed to the interpretation of the data. QLW was responsible for the collection and analysis of the data. LY provided expertise in solving statistical issues and contributed to the revision of the article.All raw data generated or analysed during the course of this study can be obtained from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of the West China Second University Hospital of Sichuan University (reference number:\u0026nbsp;2016(010)).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll methods and procedures were conducted in strict accordance with the relevant guidelines and regulations. Written informed consent was obtained from all participants before their inclusion in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to publish\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent for publication was obtained from all participants.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMarston C(2006)Report of a WHO Technical Consultation on Birth Spacing. Geneva, Switzerland, World Health Organization WHO. 50(2):137.\u003c/li\u003e\n\u003cli\u003eXie M, Lao TT, Du M, Sun Q, Qu Z, Ma J, et al(2019) Risk for Cesarean section in women of advanced maternal age under the changed reproductive policy in China: A cohort study in a tertiary hospital in southwestern China. J Obstet Gynaecol Res 45(9):1866-75.\u003c/li\u003e\n\u003cli\u003eYan,J,Yan J,Wang L,Yang Y,Zhang Y,Zhang H,et al(2020)The trend of caesarean birth rate changes in China after \u0026apos;universal two-child policy\u0026apos; era: a population-based study in 2013-2018. BMC Med 18(1): p. 249.\u003c/li\u003e\n\u003cli\u003eLiang Y,Zhang L,Huang L,Li Y,Chen J,Bi S,et al(2023)Association between short inter-pregnancy interval and placenta previa and placenta accreta spectrum with respect to maternal age at first cesarean delivery. J Matern Fetal Neonatal Med 36(1): p. 2192853.\u003c/li\u003e\n\u003cli\u003eChiossi G,D\u0026apos;Amico R,Tramontano A L,Sampogna V,Laghi V,Facchinetti(2021)Prevalence of uterine rupture among women with one prior low transverse cesarean and women with unscarred uterus undergoing labor induction with PGE2: A systematic review and meta-analysis. PLoS One 16(7): p. e0253957.\u003c/li\u003e\n\u003cli\u003eHochler H, Wainstock T, Lipschuetz M, Sheiner E, Ezra Y, Yagel S, et al(2020) Grandmultiparity, maternal age, and the risk for uterine rupture-A multicenter cohort study. Acta Obstet Gynecol Scand 99(2):267-73.\u003c/li\u003e\n\u003cli\u003eTimofeev J, Reddy UM, Huang CC, Driggers RW, Landy HJ, Laughon SK(2013) Obstetric complications, neonatal morbidity, and indications for cesarean delivery by maternal age. Obstet Gynecol 122(6):1184-95.\u003c/li\u003e\n\u003cli\u003eDietl A, Farthmann J(2015)Gestational hypertension and advanced maternal age. Lancet (London, England) 386(10004):1627-8.\u003c/li\u003e\n\u003cli\u003eTian M L,Ma G J,Du LY,Jin Y,Zhang C,Xiao Y G,et al(2023)The Effect of 2016 Chinese second-child policy and different maternal age on pregnancy outcomes in Hebei Province, China. BMC Pregnancy Childbirth 23(1): p. 267.\u003c/li\u003e\n\u003cli\u003eZhang, H. and W. Wang(2022) Risk factors and adverse pregnancy outcomes in older pregnant women with hypertensive disorders of pregnancy. J Obstet Gynaecol Res 48(7): p. 1710-1720.\u003c/li\u003e\n\u003cli\u003eBi S,Zhang L,Chen J,Huang M,Huang L,Zeng S,et al(2021) Maternal age at first cesarean delivery related to adverse pregnancy outcomes in a second cesarean delivery: a multicenter, historical, cross-sectional cohort study. BMC Pregnancy Childbirth 21(1): p. 126.\u003c/li\u003e\n\u003cli\u003eFrick, A.P(2021) Advanced maternal age and adverse pregnancy outcomes. Best Pract Res Clin Obstet Gynaecol 70: p. 92-100.\u003c/li\u003e\n\u003cli\u003eChen I, Jhangri GS, Chandra S(2014) Relationship between interpregnancy interval and congenital anomalies. Am J Obstet Gynecol 210(6):564.e1-8.\u003c/li\u003e\n\u003cli\u003eMa Y,Fu H,Li Y,Bao Z R,Dong W B,Lei X P(2023)Interactions between long interpregnancy interval and advanced maternal age on neonatal outcomes. World J Pediatr 19(12):1155-1161.\u003c/li\u003e\n\u003cli\u003eYe L, Cao W, Yao J, Peng G, Zhou R(2019)Systematic review of the effects of birth spacing after cesarean delivery on maternal and perinatal outcomes. Int J Gynaecol Obstet 147(1):19-28.\u003c/li\u003e\n\u003cli\u003eVanobberghen F,Lweno O,Kuemmerle A,Mwebi K D,Asilia P,Issa A,et al(2021)Efficacy and safety of intravenous ferric carboxymaltose compared with oral iron for the treatment of iron deficiency anaemia in women after childbirth in Tanzania: a parallel-group, open-label, randomised controlled phase 3 trial. Lancet Glob Health 9(2): p. e189-e198.\u003c/li\u003e\n\u003cli\u003eTranquilli AL, Dekker G, Magee L, Roberts J, Sibai BM, Steyn W, et al(2014) The classification, diagnosis and management of the hypertensive disorders of pregnancy: A revised statement from the ISSHP. Pregnancy Hypertens 4(2):97-104.\u003c/li\u003e\n\u003cli\u003eDiagnosis and classification of diabetes mellitus(2013) Diabetes Care 36 Suppl 1(Suppl 1):S67-74.\u003c/li\u003e\n\u003cli\u003eAl-Zirqi I, Stray-Pedersen B, Fors\u0026eacute;n L, Daltveit AK, Vangen S(2013)Validation study of uterine rupture registration in the Medical Birth Registry of Norway. Acta Obstet Gynecol Scand 92(9):1086-93.\u003c/li\u003e\n\u003cli\u003eLydon-Rochelle M, Holt VL, Easterling TR, Martin DP(2001) Risk of uterine rupture during labor among women with a prior cesarean delivery. N Engl J Med 345(1):3-8.\u003c/li\u003e\n\u003cli\u003eAnanth CV, Oyelese Y, Yeo L, Pradhan A, Vintzileos AM(2005)Placental abruption in the United States, 1979 through 2001: temporal trends and potential determinants. Am J Obstet Gynecol 192(1):191-8.\u003c/li\u003e\n\u003cli\u003eGebremedhin A T, Tessema G A, Regan A K, et al(2021)Association between interpregnancy interval and hypertensive disorders of pregnancy: Effect modification by maternal age. Paediatr Perinat Epidemiol 35(4):415-424.\u003c/li\u003e\n\u003cli\u003eSmith Devin D, Merriam Audrey A, Jung Julley, et al(2018) Effect of Maternal Age and Fetal Number on the Risk of Hypertensive Disorders of Pregnancy. Am J Perinatol 35(3): 311-316. \u003c/li\u003e\n\u003cli\u003eSarah C. Haight, Carol J. Hogue, Cheryl L, et al(2019) Short interpregnancy intervals and adverse pregnancy outcomes by maternal age in the United States. Ann Epidemiol 31(1):38-44.\u003c/li\u003e\n\u003cli\u003eConde-Agudelo A, Beliz\u0026aacute;n JM(2000) Maternal morbidity and mortality associated with interpregnancy interval: cross sectional study. BMJ 321(7271):1255-9.\u003c/li\u003e\n\u003cli\u003eConde-Agudelo A, Rosas-Berm\u0026uacute;dez A, Kafury-Goeta AC(2006) Birth spacing and risk of adverse perinatal outcomes: a meta-analysis. Jama 295(15):1809-23\u003c/li\u003e\n\u003cli\u003eClass QA, Rickert ME, Oberg AS, Sujan AC, Almqvist C, Larsson H, et al(2017) Within-Family Analysis of Interpregnancy Interval and Adverse Birth Outcomes. Obstet Gynecol 130(6):1304-11.\u003c/li\u003e\n\u003cli\u003eZhu BP, Rolfs RT, Nangle BE, Horan JM(1999) Effect of the interval between pregnancies on perinatal outcomes. N Engl J Med 340(8):589-94.\u003c/li\u003e\n\u003cli\u003eBujold E, Mehta SH, Bujold C, Gauthier RJ(2002) Interdelivery interval and uterine rupture. Am J Obstet Gynecol 187(5):1199-202.\u003c/li\u003e\n\u003cli\u003eBirara M, Gebrehiwot Y(2013)Factors associated with success of vaginal birth after one caesarean section (VBAC) at three teaching hospitals in Addis Ababa, Ethiopia: a case control study. BMC Pregnancy Childbirth 13:31.\u003c/li\u003e\n\u003cli\u003eAl-Zirqi I, Daltveit AK, Fors\u0026eacute;n L, Stray-Pedersen B, Vangen S(2017) Risk factors for complete uterine rupture. Am J Obstet Gynecol 216(2):165.e1-.e8.\u003c/li\u003e\n\u003cli\u003eFaiz AS, Ananth CV(2003)Etiology and risk factors for placenta previa: an overview and meta-analysis of observational studies. J Matern Fetal Neonatal Med 13(3):175-90.\u003c/li\u003e\n\u003cli\u003eOgawa K, Urayama KY, Tanigaki S, Sago H, Sato S, Saito S, et al(2017) Association between very advanced maternal age and adverse pregnancy outcomes: a cross sectional Japanese study. BMC Pregnancy Childbirth 17(1):349.\u003c/li\u003e\n\u003cli\u003eWennberg AL, Opdahl S, Bergh C, Aaris Henningsen AK, Gissler M, Romundstad LB, et al(2016) Effect of maternal age on maternal and neonatal outcomes after assisted reproductive technology. Fertil Steril 106(5):1142-9.e14.\u003c/li\u003e\n\u003cli\u003eHanley GE, Hutcheon JA, Kinniburgh BA, Lee L(2017) Interpregnancy Interval and Adverse Pregnancy Outcomes: An Analysis of Successive Pregnancies. Obstet Gynecol 129(3):408-15.\u003c/li\u003e\n\u003cli\u003eDairo MD, Lawoyin TO(2004)Socio-demographic determinants of anaemia in pregnancy at primary care level: a study in urban and rural Oyo State, Nigeria. Afr J Med Med Sci 33(3):213-7.\u003c/li\u003e\n\u003cli\u003eGurol-Urganci I, Bou-Antoun S, Lim CP, Cromwell DA, Mahmood TA, Templeton A, et al(2013)Impact of Caesarean section on subsequent fertility: a systematic review and meta-analysis. Hum Reprod 28(7):1943-52.\u003c/li\u003e\n\u003cli\u003eFox NS, Gerber RS, Mourad M, Saltzman DH, Klauser CK, Gupta S, et al(2014)Pregnancy outcomes in patients with prior uterine rupture or dehiscence. Obstet Gynecol 123(4):785-9.\u003c/li\u003e\n\u003cli\u003eFitzpatrick KE, Kurinczuk JJ, Bhattacharya S, Quigley MA(2019) Planned mode of delivery after previous cesarean section and short-term maternal and perinatal outcomes: A population-based record linkage cohort study in Scotland. PLoS Med 16(9):e1002913.\u003c/li\u003e\n\u003cli\u003eHofmeyr GJ, Say L, G\u0026uuml;lmezoglu AM(2005) WHO systematic review of maternal mortality and morbidity: the prevalence of uterine rupture. BJOG 112(9):1221-8.\u003c/li\u003e\n\u003cli\u003eNielsen TF, Ljungblad U, Hagberg H(1989) Rupture and dehiscence of cesarean section scar during pregnancy and delivery. Am J Obstet Gynecol 160(3):569-73.\u003c/li\u003e\n\u003cli\u003eFogelberg M, Baranov A, Herbst A, Vikhareva O(2017) Underreporting of complete uterine rupture and uterine dehiscence in women with previous cesarean section. J Matern Fetal Neonatal Med.30(17):2058-61.\u003c/li\u003e\n\u003cli\u003eJastrow N, Roberge S, Gauthier RJ, Laroche L, Duperron L, Brassard N, et al(2010) Effect of birth weight on adverse obstetric outcomes in vaginal birth after cesarean delivery. Obstet Gynecol 115(2 Pt 1):338-43.\u003c/li\u003e\n\u003cli\u003eAlcalay M, Hourvitz A, Reichman B, Luski A, Quint J, Barkai G, et al(1996) Prelabour rupture of membranes at term: early induction of labour versus expectant management. Eur J Obstet Gynecol Reprod Biol 70(2):129-33.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1. Demographic and Clinical Characteristics in the Four Groups by Interpregnancy Interval.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"35.714285714285715%\" rowspan=\"2\"\u003e\n \u003cp\u003eCharacteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"55.10204081632653%\" colspan=\"4\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003cem\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.183673469387756%\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e24-59\u003c/p\u003e\n \u003cp\u003e(n = 89)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 290)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 196)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eDelivery age (y)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e36.22\u0026plusmn;4.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e37.46\u0026plusmn;3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e36.25\u0026plusmn;3.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e38.01\u0026plusmn;2.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.538\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eEducation (y)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026lt; 0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026le; 12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1 (6.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e4 (4.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e14 (4.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e13 (6.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e13-16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1 (6.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e6 (6.74)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e19 (6.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e26 (13.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e17-21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e8 (50.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e55 (61.80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e179 (61.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e145 (74.35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026ge;21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e6 (37.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e24 (26.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e77 (26.65)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e11 (5.64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eBMI, No. (Kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u003csup\u003e\u0026nbsp;\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.567\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026lt; 18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e3 (3.37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e8 (2.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e8 (4.08)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e18-23.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e14 (87.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e65 (73.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e226 (77.93)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e138 (70.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e24-27.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1 (6.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e16 (17.98)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e49 (16.90)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e43 (21.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026gt; 28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1 (6.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e5 (5.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e7 (2.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e7 (3.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eNumber of previous pregnancies\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026lt; 0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e11 (68.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e64 (71.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e217 (74.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e172 (87.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003e\u0026lt; 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e5 (31.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e25 (28.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e73 (25.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e24 (12.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eParity \u0026ge; 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;6 (37.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e9 (10.11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e17 (5.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e9 (4.59)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026lt; 0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003ePrior cesareans \u0026ge; 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;4 (25.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;8 (8.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e14 (4.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e4 (2.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026lt; 0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003ePrior vaginal birth\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e4 (1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e2 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.692\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eIVF-ET\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e2 (2.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e3 (1.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;2 (1.02)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.765\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003ePreexisting hypertension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1(6.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;3 (1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.107\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003ePreexisting diabetes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e1 (1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e2 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e2 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.946\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eGestational age at delivery (weeks)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e37.88\u0026plusmn;1.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e37.58\u0026plusmn;3.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e37.86\u0026plusmn;2.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e37.72\u0026plusmn;2.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.857\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eMode of delivery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.311\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eRepeated cesarean section\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e16 (100.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e85 (95.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e278 (95.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e193 (98.47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eVaginal birth after CS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e0 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e4 (4.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;12 (4.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e3 (1.53)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eType of repeated cesarean section\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eEmergency cesarean section\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e7 (43.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e31 (34.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e92 (31.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e71 (36.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.614\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.458333333333336%\"\u003e\n \u003cp\u003eCS with indications\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e10 (62.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e25 (28.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e80 (27.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.541666666666666%\"\u003e\n \u003cp\u003e\u0026nbsp;53 (27.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.375%\"\u003e\n \u003cp\u003e0.352\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are expressed as mean \u0026plusmn; SD, or n (%) with p-value from exact chi-square.\u003c/p\u003e\n\u003cp\u003eBMI, body mass index; IVF-ET, in vitro fertilization and embryo transfer.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2. Rates of Maternal and Neonatal outcomes in the Four Groups by Interpregnancy Interval.\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"699\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"31.044349070100143%\" rowspan=\"2\"\u003e\n \u003cp\u003ePerinatal outcome\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"56.509298998569385%\" colspan=\"4\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003cem\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.446351931330472%\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e24-59\u003c/p\u003e\n \u003cp\u003e(n = 89)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 290)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 196)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eAnemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;1 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e7 (7.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e34 (11.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e24 (12.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.641\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eGHP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e4 (2.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (4.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e7 (2.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e12 (6.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e\u0026lt; 0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eGDM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.176\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eGrade A1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e11 (68.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e59 (66.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e210 (72.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e123 (62.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eGrade A2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e4 (25.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e27 (30.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e67 (23.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e67 (34.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePlacenta inherence\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e6 (6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e24 (8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e19 (9.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.525\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePlacental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.255\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eNormal\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e13 (81.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e81 (91.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e266 (91.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e165 (84.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eLow placenta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e1 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e10 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e14 (7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePartial or marginal placenta previa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e6 (3.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\" rowspan=\"2\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"35.39967373572594%\"\u003e\n \u003cp\u003eComplete placenta previa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.150081566068515%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.150081566068515%\"\u003e\n \u003cp\u003e2 (2.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.150081566068515%\"\u003e\n \u003cp\u003e12 (4.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.150081566068515%\"\u003e\n \u003cp\u003e11 (5.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePernicious placenta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e1 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e18 (6.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;9 (4.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.713\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eplacenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e6 (6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e24 (8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e19 (9.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.525\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e12 (13.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e\u0026nbsp;39 (13.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e39 (19.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.241\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e1 (1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.946\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eplacental abruption\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e1 (0.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.718\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.787\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e1 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e5 (5.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e6 (2.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3 (1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.147\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePreterm birth\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e4 (25.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e11 (12.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e38 (13.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e30 (15.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.518\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003ePreterm birth \u0026lt; 34 weeks\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e5 (5.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e10 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e12 (6.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.406\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eBirth weight (g)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3197\u0026plusmn;576\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3211\u0026plusmn;649\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3265\u0026plusmn;647\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e3188\u0026plusmn;531\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.566\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eBirth length (cm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e48.81\u0026plusmn;2.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e48.91\u0026plusmn;3.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e48.88\u0026plusmn;4.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e48.83\u0026plusmn;2.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.998\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eLBW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e8 (8.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e23 (7.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e22 (11.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.635\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e5 (5.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e11 (3.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e9 (4.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.722\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"31%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e2 (12.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e9 (10.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e35 (12.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.142857142857142%\"\u003e\n \u003cp\u003e22 (11.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.428571428571429%\"\u003e\n \u003cp\u003e0.994\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are expressed as mean \u0026plusmn; SD, or n (%) with p-value from exact chi-square.GDM, gestational diabetes mellitus; GHP, gestational hypertension; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLBW, the birth weight of newborns is less than 2500g; NICU, neonatal intensive care.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3. Association of Anemia, GHP, GDM and IPI in the Three Groups with IPI of \u0026lt;24 months, 60-119 months and \u0026ge; 120 months.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.00405953991881%\" rowspan=\"3\"\u003e\n \u003cp\u003eOutcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"76.99594046008119%\" colspan=\"6\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"36.8421052631579%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"31.57894736842105%\" colspan=\"2\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"31.57894736842105%\" colspan=\"2\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"24.077328646748683%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.829525483304042%\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"20.38664323374341%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.24780316344464%\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.49560632688928%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.963093145869948%\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.00405953991881%\" valign=\"top\"\u003e\n \u003cp\u003eAnemia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.53856562922869%\" valign=\"top\"\u003e\n \u003cp\u003e1.324(0.14-12.46)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.878213802435724%\" valign=\"top\"\u003e\n \u003cp\u003e0.796\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.696887686062245%\" valign=\"top\"\u003e\n \u003cp\u003e0.648(0.27-1.53)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.660351826792963%\" valign=\"top\"\u003e\n \u003cp\u003e0.323\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.320703653585927%\" valign=\"top\"\u003e\n \u003cp\u003e0.703(0.28-1.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.901217861975643%\" valign=\"top\"\u003e\n \u003cp\u003e0.449\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.00405953991881%\"\u003e\n \u003cp\u003eGHP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.53856562922869%\" valign=\"top\"\u003e\n \u003cp\u003e0.688(0.17-2.77)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.878213802435724%\" valign=\"top\"\u003e\n \u003cp\u003e0.598\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.696887686062245%\" valign=\"top\"\u003e\n \u003cp\u003e0.932(0.43-5.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.660351826792963%\" valign=\"top\"\u003e\n \u003cp\u003e0.472\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.320703653585927%\" valign=\"top\"\u003e\n \u003cp\u003e16.223(2.73-96.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.901217861975643%\" valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"23.00405953991881%\"\u003e\n \u003cp\u003eGDM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.53856562922869%\" valign=\"top\"\u003e\n \u003cp\u003e1.043(0.31-3.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.878213802435724%\" valign=\"top\"\u003e\n \u003cp\u003e0.946\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.696887686062245%\" valign=\"top\"\u003e\n \u003cp\u003e0.715(0.42-1.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.660351826792963%\" valign=\"top\"\u003e\n \u003cp\u003e0.213\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.320703653585927%\" valign=\"top\"\u003e\n \u003cp\u003e0.902(0.52-1.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.901217861975643%\" valign=\"top\"\u003e\n \u003cp\u003e0.717\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI, interpregnancy interval.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; GHP, gestational hypertension; GDM, gestational diabetes mellitus.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAdjusted for education status, gravidity, parity, number of previous cesarean section.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4. Association of other Perinatal Outcomes and IPI in the Three Groups with IPI of \u0026lt;24 months, 60-119 months and \u0026ge; 120 months (without adjusting for any confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.39393939393939%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.080808080808081%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"44.44444444444444%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.080808080808081%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e39.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e2.337 (0.55-9.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.914(0.40-2.11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.902(0.84-4.33)\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.271\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e32.644\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.52(0.05-5.37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.53 (0.15-1.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.73(019-2.74)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.765\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;35.875\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.92(0.19-4.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.097(0.50-2.70)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.59(0.79-3.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.181\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e19.821\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.89(1.13-1.87)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.61(0.05-6.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.91(0.08-10.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.85(0.63-1.48)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e2.48(0.76-8.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e3.69(0.68-12.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.997\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e0.74(0.62-1.38)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.18(0.74-1.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.27(0.52-3.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.564\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"bottom\"\u003e\n \u003cp\u003e37.565\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e1.55(0.45-4.63)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.62(0.33-1.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.68(0.12-3.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.20618556701031%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e38.616\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.27(0.25-6.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.22(0.56-2.65)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.43298969072165%\" valign=\"top\"\u003e\n \u003cp\u003e1.124(0.49-2.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.24742268041237%\" valign=\"top\"\u003e\n \u003cp\u003e0.356\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;IPI,interpregnancy interval.\u0026nbsp; \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5. Association of other Perinatal Outcomes and IPI in the Three Groups with IPI of \u0026lt;24 months, 60-119 months and \u0026ge; 120 months (with adjusting for some confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\" width=\"99%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.4040404040404%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.0606060606060606%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.070707070707071%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.545454545454547%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.36363636363637%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.09090909090909%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"29.545454545454547%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"36.36363636363637%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"34.09090909090909%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e12.971\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e1.72(0.37-8.11)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e0.862(0.36-2.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.885(0.79-4.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.286\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e10.848\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e1.68(0.15-18.65)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e2.134(0.58-7.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.19(0.29-4.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.318\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e0.934\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e0.77(0.14-4.27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e1.06(0.50-2.25)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.56(0.72-3.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.334\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e1.07(0.96-1.53)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e0.55\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;(0.046-6.49)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e0.57\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;(0.05-6.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.991\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e0.43(0.23-6.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e1.54(0.87-5.43)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.91(0.75-7.59)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.994\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e0.163\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e0.78(0.56-4.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e1.41(0.78-3.52)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.63(0.57-3.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.612\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e1.588\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e1.84(0.40-3.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e0.69(0.22-2.17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e0.55(0.15-1.93)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.208\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.23711340206186%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.185567010309279%\" valign=\"top\"\u003e\n \u003cp\u003e5.572\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.402061855670103%\" valign=\"top\"\u003e\n \u003cp\u003e1.403(0.27-7.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.49484536082474%\" valign=\"top\"\u003e\n \u003cp\u003e1.293(0.59-2.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.463917525773196%\" valign=\"top\"\u003e\n \u003cp\u003e1.071(0.46-2.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.216494845360825%\" valign=\"top\"\u003e\n \u003cp\u003e0.184\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI,interpregnancy interval.\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\u003cp\u003eAadjusted for education status, gravidity, parity, number of previous cesarean section.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6. Association of IPI and other Perinatal Outcomes in Emergency Cesarean Section (without adjusting for any confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.05390539053906%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.36083608360836%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"44.33443344334434%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.250825082508252%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e13.379\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e4.83(0.56-41.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.82(0.15-4.48)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e2.38(0.49-11.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.381\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e11.195\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.23(0.01-4.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.74(0.08-6.90)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.44(0.05-3.93)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.526\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e8.228\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.88(0.14-5.34)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.68(0.26-1.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.38(0.14-0.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.822\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.38(0.84-1.95)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.68(0.47-1.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.51(0.23-1.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.997\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.225\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.91(0.37-1.47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.34(0.63-2.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.64(0.43-4.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.285\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.67(0.36-1.45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.25(0.7-2.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.83(0.74-4.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.283\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e13.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.65(0.5-6.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.76(0.18-3.14)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.86(0.20-3.69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.287\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.045\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.87(0.59-1.45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.14(0.64-1.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.17(0.45-2.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.748\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI, interpregnancy interval.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 7. Association of IPI and other Perinatal Outcomes in Emergency Cesarean Section (with adjusting for some confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.05390539053906%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.36083608360836%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"44.33443344334434%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.250825082508252%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e3.95(0.39-39.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.72(0.13-4.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e2.3(0.41-13.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.996\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e3.97(0.15-108.27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.15(0.11-14.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.82(0.14-23.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.997\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.493\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.13(0.18-7.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.53(0.58-4.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e2.6(0.94-7.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.48\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.057\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.27(0.74-1.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.96(0.71-1.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.83(0.48-1.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.993\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.185\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.72\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;(0.34-1.69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.11(0.57-2.47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.58(0.35-5.64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.538\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.73(0.37-1.72)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.31(0.81-2.54)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.57(0.6-4.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.464\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.67(0.57-8.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.94(0.17-4.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.68(0.12-3.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.937\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.331\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.83(0.59-1.26)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.48(0.84-2.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.85(0.99-4.37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.112\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI, interpregnancy interval.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\u003cp\u003eAdjusted for education status, gravidity, parity, number of previous cesarean section.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 8. Association of IPI and other Perinatal Outcomes in Selective Cesarean Section (without adjusting for any confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.05390539053906%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.36083608360836%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"44.33443344334434%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.250825082508252%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e23.062\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.14(0.12-10.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.91(0.34-2.41)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.66(0.63-4.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.348\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without\u0026nbsp;placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e20.44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.86(0.44-1.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e2.12(0.47-9.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.88(0.16-4.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.211\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e23.627\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.97(0.58-10.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.64(0.21-2.15)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.76(0.21-2.72)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.015\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e15.471\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.25(0.81-8.92)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.29(0.02-4.66)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.44\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;(0.03-7.14）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.028\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.89(0.62-1.45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.11(0.84-1.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.12(0.65-2.31)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.996\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e1.334\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.21\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;(0.66-1.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.89(0.64-1.81)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.78(0.65-1.92)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.813\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e20.444\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.31(0.55-2.95)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.57(0.10-3.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.66(0.11-4.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.082\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.228\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.13(0.35-4.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.87(0.13-3.83)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.84(0.07-3.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.727\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI, interpregnancy interval.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTable 9. Association of IPI and other Perinatal Outcomes in Selective Cesarean Section (with adjusting for some confounding factors).\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.05390539053906%\" rowspan=\"3\"\u003e\n \u003cp\u003ePerinatal outcomes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.36083608360836%\" rowspan=\"3\"\u003e\n \u003cp\u003eindex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"44.33443344334434%\" colspan=\"3\"\u003e\n \u003cp\u003eInterpregnancy interval (mon)\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.250825082508252%\" rowspan=\"3\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cstrong\u003evalue\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt; 24\u003c/p\u003e\n \u003cp\u003e(n = 121)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e60-119\u003c/p\u003e\n \u003cp\u003e(n = 712)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u0026ge; 120\u003c/p\u003e\n \u003cp\u003e(n = 246)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eaOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eAbnormal placental position\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e9.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.39(0.03-5.08)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.91(0.32-2.56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.98(0.69-5.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.249\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePernicious placenta with or without placenta accreta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e6.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.8(0.46-1.71)\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e2.32(0.47-11.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.601(0.08-4.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.131\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePROM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.421\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.86(0.46-1.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.14(0.72-1.42)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.28(0.6-1.84)\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.637\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003eIncomplete Uterine rupture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.006\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.59(0.83-2.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.24(0.01-4.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.23(0.01-4.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.996\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"bottom\"\u003e\n \u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.155\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.26(0.09-1.46)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.57(0.81-1.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.76(0.45-3.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.995\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\" valign=\"top\"\u003e\n \u003cp\u003eHysterectomy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e0.314\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.77(0.52-2.21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.25(0.73-1.81)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.42(0.45-2.68)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.508\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003e1-min Apgar score \u0026lt;10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e3.125\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.23(0.51-3.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.98(0.2-2.93)\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.88(0.22-5.99)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.711\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"39.096916299559474%\"\u003e\n \u003cp\u003eNICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.370044052863436%\" valign=\"top\"\u003e\n \u003cp\u003e1.259\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e1.34(0.37-7.77)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.67(0.24-3.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.757709251101321%\" valign=\"top\"\u003e\n \u003cp\u003e0.49(0.15-1.37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"8.259911894273127%\" valign=\"top\"\u003e\n \u003cp\u003e0.814\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eIPI, interpregnancy interval.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e*\u003c/sup\u003e, using IPI of 24-59 months as reference category.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eaOR, adjusted odds ratio; CI, confidential index; PROM, premature rupture of membrane.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAbnormal placental position, including low placenta, partial and complete placenta previa.\u003c/p\u003e\n\u003cp\u003eAdjusted for education status, gravidity, parity, number of previous cesarean section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Interpregnancy interval, Caesarean delivery, Perinatal outcomes, Advanced maternal age,, Caesarean section","lastPublishedDoi":"10.21203/rs.3.rs-4089431/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4089431/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e This study aims to evaluate the impact of different interpregnancy intervals (IPIs) after a previous caesarean section on perinatal events in elderly multiparous women.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eIn this retrospective cohort study, multiparous women of advanced maternal age who had a previous caesarean section between January 1, 2016, and December 31, 2016, were included.IPI was defined as the duration between live birth and subsequent conception.Multivariate logistic regression analysis was used to assess the association between variant IPIs (\u0026lt;24 months, 60-119 months, and ≥120 months) and perinatal outcomes, with an IPI of 24-59 months as the reference group.The risks of anemia, gestational hypertension, gestational diabetes mellitus,placenta previa,premature rupture of membrane,uterine rupture and successful vaginal were compared among the 4 groups.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eWe recorded a total of 591 births following cesarean delivery: 16, 89, 290, and 196 births in the IPI \u0026lt; 24 months, 24-59 months, 60-119 months, and ≥120 months groups, respectively. Women with an IPI of ≥120 months had a significantly higher incidence of gestational hypertension (6.1%, p＜0.001) than the other three groups. In women with a prior caesarean delivery and an IPI＜ 24 months, there was an increased risk of incomplete uterine rupture (OR 1.89, 95% CI 1.13-1.87) and low 1-minute Apgar scores (OR 1.55, 95% CI 0.45-4.63). The IPI did not impact the occurrence of incomplete uterine rupture in women with a history of emergency caesarean section.There was no significant association between the IPI and other adverse perinatal outcomes, such as anaemia, gestational diabetes mellitus,abnormal placental position, pernicious placenta, placenta accreta, placental abruption, postpartum haemorrhage, hysterectomy, or neonatal intensive care admission.An IPI \u0026lt;24 months was associated with higher likelihood of premature rupture (OR 1.97, 95%CI 0.58-10.2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eWomen with an IPI of ≥120 months had a higher rate of gestational hypertension compared to the other groups, while an IPI of \u0026lt;24 months increased the risk of incomplete uterine rupture and low 1-minute Apgar scores.\u003c/p\u003e","manuscriptTitle":"Impact of Interpregnancy Interval after Caesarean Section on Perinatal Outcomes in Multiparous Women of Advanced Maternal Age: A Retrospective Cohort Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-15 19:47:55","doi":"10.21203/rs.3.rs-4089431/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"26a51080-f296-42cf-ac6b-eee06bfa560b","owner":[],"postedDate":"March 15th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-21T20:14:17+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-15 19:47:55","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4089431","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4089431","identity":"rs-4089431","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}