{"paper_id":"2f47e6a5-1573-4015-bfd4-9415ab24a8ef","body_text":"Exploring the Optimal Intertwin Delivery Interval for Vaginal Delivery | 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 Exploring the Optimal Intertwin Delivery Interval for Vaginal Delivery Naphtali Justman, Roee Goldfriend, Bar Rosh, Amir Wolfovitch, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3043327/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 29 Feb, 2024 Read the published version in Reproductive Sciences → Version 1 posted 4 You are reading this latest preprint version Abstract Objective The effect of prolonged intertwin delivery interval (IDI) is not well studied. This work aimed to assess the inflection point for Cesarean delivery (CD) and associated adverse maternal and neonatal outcomes. Methods This was a retrospective cohort study at a single tertiary care center. The study included women with twin pregnancies in 2010–2019 who reached the second stage of labor, and assessed the most predictive cutoff for CD using Youden J statistic and compared adverse maternal and neonatal outcomes between short and prolonged intertwin delivery intervals. Results A total of 461 gravidas reached the second stage of labor and were included in the study. Using the ROC curve and Youden J statistic, the IDI cutoff was set at 15 min (80% sensitivity, 75% specificity, p < 0.001), with 312 women in the short and 149 in the prolonged IDI groups. Women in the prolonged IDI group were less likely to deliver the second twin vaginally (75.8% vs. 93.3%, p < 0.001). Postpartum hemorrhage (PPH) (39.1% vs. 24.7%, p = 0.01), and placental abruption (4% vs. 1%, p = 0.03) were more likely to occur in the prolonged IDI group. An increased rate of neonatal acidemia and low 5-minute Apgar score were also found in the prolonged IDI group (15.7% vs. 4.3%, P = 0.01, 9.7% vs. 3.5%, p = 0.008; respectively). Conclusion IDIs of more than 15 min are associated with increased risk of adverse maternal and neonatal outcomes. These findings should be used for counseling and managing twin pregnancies attempting vaginal delivery. Cutoff Intertwin delivery interval Maternal morbidity Neonatal morbidity Twin gestations Vaginal delivery Figures Figure 1 Figure 2 Introduction Twin pregnancy incidence has increased in recent years in parallel with the rising use and availability of assisted reproductive technologies. In 2021, twin births account for approximately 3% of all live births in the United States.[ 1 – 3 ] The Twin Birth Study and others that followed demonstrated the safety of vaginal delivery (VD) in monochorionic-diamniotic and dichorionic-diamniotic twin pregnancies. Currently, vaginal delivery is recommended when the leading twin is in vertex presentation.[ 4 – 6 ] Prolonged inter-twin delivery interval (IDI) refers to a time gap exceeding 15–30 min between the delivery of the first and the second twin.[ 7 – 11 ] The IDI and its effect on neonatal outcomes are under debate, with some reports suggesting that when fetal well-being is assured, IDI length has no effect on neonatal outcomes.[ 12 – 15 ] In contrast, others have demonstrated increased rate of neonatal acidemia and low Apgar scores with prolonged IDI.[ 7 – 11 ] Prolonged IDI has also been associated with a 4-8-fold increase in Cesarean delivery (CD) rate of the second twin, possibly due to fetal malpresentation, umbilical cord prolapses, and more.[ 8 , 9 , 15 – 18 ] Reported maternal morbidity mostly related to the surgical procedure, including a higher rate of puerperal infection and longer postpartum hospital stay.[ 16 , 19 ] This study aimed to define the inflection point of the IDI associated with CD and to assess the effect of prolonged IDI on adverse maternal and neonatal outcomes. Methods Study design This was a retrospective cohort study conducted at a single academic tertiary center between January 2010 and December 2019. The study was approved by the hospital's IRB (Rambam Hospital institutional review board 0153-20-RMB), and the IRB waived the necessity of obtaining informed consent from the gravidas due to the retrospective nature of the study. Study population The study included women with twin pregnancies who attempted VD and reached the second stage of labor. Excluded were women with pregnancies complicated by intra-uterine fetal demise (IUFD), non-vertex presentation of the first twin, CD of the first twin, gestational age < 24 weeks, determined based on first-semester crown-rump length measurements, and fetal abnormalities. Data collection Maternal and neonatal data were collected using electronic medical records and manual retrieval of non-parametric pregnancy outcomes from the hospital's electronic record system. The data was stored in a coded SPSS file. Study outcomes The primary outcome was the inflection point of IDI for a CD. Baseline maternal demographics, clinical characteristics and neonatal and maternal outcomes following an attempted vaginal delivery of twins were compared between short and prolonged IDI as defined by the inflection point found. Secondary outcomes included the rate of placental abruption, chorioamnionitis, postpartum hemorrhage (PPH) (defined as hemoglobin drop > 3 gr/dL), need for blood transfusion, length of hospital stay and advanced perineal lacerations. In addition, the association between prolonged IDI (defined as IDI > 15 minutes) and a composite of adverse maternal outcomes, including at least one of the following was assessed: placental abruption, PPH, need for blood transfusion, 3rd/4th-degree perineal laceration and puerperal fever ≥ 38°C. In addition, the rate of neonatal mortality, 5-minute Apgar score < 7, neonatal acidemia (defined as cord arterial pH ≤ 7.1), admission to the neonatal intensive care unit (NICU), and length of NICU stay were evaluated. Additionally, secondary maternal and neonatal outcomes of deliveries following short vs. prolonged IDI were compared based on the time interval associated with the highest sensitivity and specificity for a CD. Statistical analysis SPSS v.28th (SPSS, Inc., Chicago, IL) was used for statistical analyses. The receiver operating characteristic (ROC) curve and Youden J statistics were used to determine the most predictive inflection point for CD. The highest J statistics represents the point where the sensitivity and specificity yield the optimum cutoff point. Following the determination of the optimum cutoff, we compared baseline characteristics and maternal and neonatal outcomes between the groups. The Chi-squared test or Fisher exact test was used to analyze categorical variables. The Mann-Whitney or the student's t-test was used to compare non-normally distributed and normally distributed continuous variables. All tests were two-sided and considered statistically significant at p value < 0.05. Results During the study period, 499 women with twin gestation reached the second stage of labor. Thirty-eight women were excluded from the analysis due to intrauterine fetal death, major fetal abnormalities or delivery at a gestational age of < 24 weeks. Based on the ROC curve (AUC 0.838, p < 0.001) and the Youden J statistics, the IDI inflection point was 15 min (sensitivity – 80%; specificity – 75%), (Fig. 1 , Table 1 ). A total of 461 women were included in the final analysis, 312 in the short IDI group (IDI ≤ 15 minutes) and 149 women in the prolonged IDI group (IDI > 15 minutes) (Fig. 2 ). Table 1 – IDI, sensitivity, specificity, and J statistic for CD IDI (minutes) Sensitivity Specificity J - statistic 5 1.000 0.288 0.288 10 0.933 0.582 0.516 15 0.800 0.747 0.547 20 0.567 0.838 0.404 25 0.467 0.893 0.360 30 0.333 0.930 0.264 35 0.267 0.947 0.213 40 0.167 0.965 0.132 45 0.133 0.977 0.110 Abbreviations: IDI, intertwin delivery interval. Baseline maternal demographics and clinical characteristics are presented in Table 2 . Women in the prolonged IDI group were statistically older than women in the short IDI group (32.1 ± 4.7 years vs. 31.3 ± 4.7 years, p = 0.03). All other baseline characteristics were similar between the groups. The mean IDI difference between the groups was 22 min (7.2 ± 3.5 min vs. 29.2 ± 20.3 min, p < 0.001). Table 2 Maternal Demographics and Clinical Characteristics Intertwin interval ≤ 15 minutes (n = 312) Intertwin interval > 15 minutes (n = 149) p value Maternal age (years) mean ± SD 31.3 ± 4.7 32.1 ± 4.7 0.03 Body mass index (kg/m 2 ) mean ± SD 30.3 ± 12.9 30.7 ± 4.8 0.8 Nulliparous, n (%) 96 (30.8) 56 (37.6) 0.15 Dichorionic – Diamniotic twins, n (%) 253 (82.7) 131 (88.5) 0.11 Induction of labor, n (%) 125 (32.5) 24 (31.6) 0.88 Epidural analgesia, n (%) 269 (86.8) 123 (83.1) 0.30 Gestational age at delivery (weeks) mean ± SD 36.2 ± 2.6 35.9 ± 2.7 0.20 2nd stage of labor (minutes) mean ± SD 53.1 ± 67.2 53.0 ± 65.5 0.80 Birthweight twin I (g) mean ± SD Birthweight twin II (g) mean ± SD Delta birthweight (g) mean ± SD 2397 ± 523 2,360 ± 496 -36.9 ± 330.5 2,352 ± 572 2,379 ± 573 27.2 ± 397.2 0.30 0.69 0.11 Intertwin delivery interval (minutes) mean ± SD 7.2 ± 3.5 29.2 ± 20.3 < 0.001 Maternal outcomes are presented in Table 3 . Prolonged IDI was associated with increased CD rate (16.8% vs. 1.6%, p < 0.001), PPH (39.1% vs. 24.7% p = 0.01), placental abruption (4% vs. 1%, p = 0.03) and a composite adverse maternal outcome (30.2% vs. 19.9%, p = 0.01). The rates of advanced perineal tears and chorioamnionitis were similar between the groups. Table 3 Maternal Outcomes Intertwin interval ≤ 15 minutes (n = 312) Intertwin interval > 15 minutes (n = 149) P -value Vaginal delivery of the 2nd twin, n (%) 291 (93.3) 113 (75.8) < 0.001 VE of the 2nd twin, n (%) 16 (5.1) 11 (7.4) Cesarean delivery of the 2nd twin, n (%) 5 (1.6) 25 (16.8) Hospital stay (days) median 4 4 0.15 PPH, n (%) 44 (24.7) 36 (39.1) 0.01 3rd /4th -degree laceration, n (%) 1 (0.3) 1 (0.7) 0.59 Chorioamnionitis, n (%) 12 (3.8) 4 (2.7) 0.52 Placental abruption, n (%) 3 (1.0) 6 (4.0) 0.03 Composite adverse maternal outcomes*, n (%) 62 (19.9) 45 (30.2) 0.01 * Composite maternal outcomes include at least one of the following: placental abruption, postpartum hemorrhage, need for blood transfusion, 3rd /4th degree laceration, chorioamnionitis. Abbreviations: VE, vacuum extraction; PPH, postpartum hemorrhage Neonatal outcomes are presented in Table 4 . Neonates in the prolonged IDI group were more likely to have neonatal acidemia and low 5-minute Apgar score (15.7% vs. 4.3%, P = 0.01, 9.7% vs. 3.5%, P = 0.008; respectively). A trend of a higher NICU admission rate was demonstrated in the prolonged IDI group (34.9% vs. 27.2%, P = 0.09). Of note, the length of stay in NICU was similar between the groups. Table 4 Neonatal outcomes of the second twin as a function of intertwin delivery interval Intertwin interval ≤ 15 minutes (n = 312) Intertwin interval > 15 minutes (n = 149) p value Apgar score at 5 min ≤ 7, n, (%) 11 (3.5) 14 (9.7) 0.008 Admission to NICU, n (%) 85 (27.2) 52 (34.9) 0.09 NICU length of stay (days) mean ± SD 8.9 ± 14.3 10.6 ± 13.9 0.24 Neonatal mortality, n (%) 1 (0.3) 1. (0.7) 0.59 Arterial cord pH ≤ 7.1, n (%) 5 (4.3) 8 (15.7) 0.01 Abbreviations: NICU, neonatal intensive care unit Discussion Main findings This study evaluated the impact of prolonged IDI on maternal and neonatal outcomes and the optimum cutoff point for CD. The findings correlated a prolonged IDI of > 15 minutes with a higher rate of CD, placental abruption, and PPH. Additionally, prolonged IDI was found to be linked to a higher rate of neonatal acidemia and lower 5-minute Apgar scores. Comparison with existing literature The presented cohorts suggested that a 15-min IDI had a 80% sensitivity and 75% specificity for CD, with a 16-fold increased risk for CD with prolonged IDI. These findings corroborate previous evidence that prolonged IDI increases the risk for CD of the second twin.[ 8 , 9 , 15 , 16 , 18 ] In particular, Stein et al.[ 9 ], who conducted the largest study assessing neonatal outcomes following prolonged IDI, reported on a 12% CD rate in a prolonged IDI group compared to 0.7% in a short IDI group. Algeri et al.[ 15 ] presented a 28% increase for emergency CD of the second twin, but used a cutoff of 30 min, which might have negatively impacted their results. The association between prolonged IDI and placental abruption observed here has been shown in previous studies as well.[ 9 , 18 ] However, PPH, which may be associated with placental abruption, has not been reported before. Singleton pregnancies with a prolonged second stage are known to be associated with an increased rate of PPH, puerperal infection, and prolonged maternal hospital stay.[ 20 , 21 ] Similar to prolonged second stage in singleton pregnancies, we presented a higher rate of PPH when IDI was longer than 15 minutes, though we did not demonstrate any difference in puerperal infection or maternal hospital stay in those cases. The total duration of the second stage was similar between the groups and this suggest the PPH might result from the rapid uterine decompression or associated CD and not from the additional prolongation of the second stage of labor. The medical literature contains conflicting reports regarding the effect of prolonged IDI on neonatal acidemia and Apgar scores. Some are in agreement with the current work, showing higher neonatal acidemia and lower 5-min Apgar scores when IDI > 15 min[ 9 , 11 , 22 , 23 ], while others present no correlation at all.[ 12 , 13 , 15 ] In their evaluation of more than 4000 twin deliveries, Stein et al.[ 9 ] found an increased rate of neonatal acidemia with IDI > 30 min and a correlation between low 5-min Apgar score and IDI > 15 min. These findings might have been related to an increased incidence of placental abruption, cord prolapse and fetal distress in the prolonged IDI group. In contrast to the present results, Rayburn et al.[ 12 ], Algeri et al[ 15 ]., and Schneuber et al.[ 13 ] found no correlation between prolonged IDI and a lower pH or Apgar scores. Of note, these studies were limited by small sample sizes, which might not have been adequately powered to detect this difference as a primary outcome. In addition, Schneuber et al.[ 13 ] excluded Cesarean and vaginal-assisted deliveries from their study, which likely contributed to their favorable Apgar and pH scores. Strengths and limitations The main strength of this study was its heterogenous population of low and high-risk women of various ethnicities and parities. In addition, the analysis included a large cohort of deliveries that occurred over a ten-year period. Intrinsic limitations included the retrospective and single-center elements of the study and some data might be prone to observer and reporter bias. Conclusions and Implications In conclusion, this study suggested that the second twin should be delivered within a maximal 15-min gap from the first twin to reduce risk of adverse maternal outcomes and CD. Furthermore, IDI > 15 minutes was associated with neonatal adverse outcomes, including neonatal acidemia and low 5-minute Apgar score. These findings warrant prospective studies to evaluate which early interventions might be beneficial for both the mother and the neonate. Declarations Acknowledgments : nothing to declare. Conflict of Interest: The authors report no conflict of interest. No financial support was received for this research. Ethics approval: The study was approved by the hospital's IRB (IRB 0153-20-RMB). Consent to participate: not applicable. Consent for publication: not applicable. Availability of data and material: The data that support the findings of this study are available from the corresponding author, N. J., upon reasonable request. Code availability: not applicable. Synopsis: Intertwin delivery interval of more than 15 minutes is associated with adverse maternal outcomes, of adverse neonatal outcomes to the second twin. References Robinson C, Chauhan SP. Intrapartum management of twins. Clin Obstet Gynecol. 2004;47:248–62. https://doi.org/10.1097/00003081-200403000-00025 . 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Cite Share Download PDF Status: Published Journal Publication published 29 Feb, 2024 Read the published version in Reproductive Sciences → Version 1 posted Reviewers agreed at journal 08 Jul, 2023 Reviewers invited by journal 03 Jul, 2023 Editor assigned by journal 23 Jun, 2023 First submitted to journal 15 Jun, 2023 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. 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12:48:42\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-3043327/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-3043327/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1007/s43032-024-01497-9\",\"type\":\"published\",\"date\":\"2024-02-29T15:01:23+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":39791370,\"identity\":\"3a3f1c2e-2f56-4810-96fe-6f8824b05820\",\"added_by\":\"auto\",\"created_at\":\"2023-07-10 13:45:28\",\"extension\":\"jpg\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":36854,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eROC curve showing the area under the curve for Cesarean delivery as a factor of IDI\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Figure1.jpg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-3043327/v1/7d4254ba4f3f8502fc8ec6c3.jpg\"},{\"id\":39791371,\"identity\":\"7da2bde4-c444-411d-b1d6-8fc3961e9536\",\"added_by\":\"auto\",\"created_at\":\"2023-07-10 13:45:28\",\"extension\":\"jpg\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":86023,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eStudy population\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"Figure2.jpg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-3043327/v1/32a2d06d22dc68c93b5abd60.jpg\"},{\"id\":51958518,\"identity\":\"2740f407-f2f6-4ba7-b4ab-adda13ced9e9\",\"added_by\":\"auto\",\"created_at\":\"2024-03-04 15:17:01\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":409086,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-3043327/v1/eb692bf1-af67-458e-99e9-8c8f060fea9a.pdf\"}],\"financialInterests\":\"\",\"formattedTitle\":\"Exploring the Optimal Intertwin Delivery Interval for Vaginal Delivery\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eTwin pregnancy incidence has increased in recent years in parallel with the rising use and availability of assisted reproductive technologies. In 2021, twin births account for approximately 3% of all live births in the United States.[\\u003cspan additionalcitationids=\\\"CR2\\\" citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e] The Twin Birth Study and others that followed demonstrated the safety of vaginal delivery (VD) in monochorionic-diamniotic and dichorionic-diamniotic twin pregnancies. Currently, vaginal delivery is recommended when the leading twin is in vertex presentation.[\\u003cspan additionalcitationids=\\\"CR5\\\" citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e]\\u003c/p\\u003e \\u003cp\\u003eProlonged inter-twin delivery interval (IDI) refers to a time gap exceeding 15\\u0026ndash;30 min between the delivery of the first and the second twin.[\\u003cspan additionalcitationids=\\\"CR8 CR9 CR10\\\" citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e] The IDI and its effect on neonatal outcomes are under debate, with some reports suggesting that when fetal well-being is assured, IDI length has no effect on neonatal outcomes.[\\u003cspan additionalcitationids=\\\"CR13 CR14\\\" citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] In contrast, others have demonstrated increased rate of neonatal acidemia and low Apgar scores with prolonged IDI.[\\u003cspan additionalcitationids=\\\"CR8 CR9 CR10\\\" citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e] Prolonged IDI has also been associated with a 4-8-fold increase in Cesarean delivery (CD) rate of the second twin, possibly due to fetal malpresentation, umbilical cord prolapses, and more.[\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e, \\u003cspan additionalcitationids=\\\"CR16 CR17\\\" citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e] Reported maternal morbidity mostly related to the surgical procedure, including a higher rate of puerperal infection and longer postpartum hospital stay.[\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR19\\\" class=\\\"CitationRef\\\"\\u003e19\\u003c/span\\u003e]\\u003c/p\\u003e \\u003cp\\u003eThis study aimed to define the inflection point of the IDI associated with CD and to assess the effect of prolonged IDI on adverse maternal and neonatal outcomes.\\u003c/p\\u003e\"},{\"header\":\"Methods\",\"content\":\"\\u003cdiv id=\\\"Sec3\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStudy design\\u003c/h2\\u003e \\u003cp\\u003eThis was a retrospective cohort study conducted at a single academic tertiary center between January 2010 and December 2019. The study was approved by the hospital's IRB (Rambam Hospital institutional review board 0153-20-RMB), and the IRB waived the necessity of obtaining informed consent from the gravidas due to the retrospective nature of the study.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec4\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStudy population\\u003c/h2\\u003e \\u003cp\\u003eThe study included women with twin pregnancies who attempted VD and reached the second stage of labor. Excluded were women with pregnancies complicated by intra-uterine fetal demise (IUFD), non-vertex presentation of the first twin, CD of the first twin, gestational age\\u0026thinsp;\\u0026lt;\\u0026thinsp;24 weeks, determined based on first-semester crown-rump length measurements, and fetal abnormalities.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec5\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eData collection\\u003c/h2\\u003e \\u003cp\\u003eMaternal and neonatal data were collected using electronic medical records and manual retrieval of non-parametric pregnancy outcomes from the hospital's electronic record system. The data was stored in a coded SPSS file.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec6\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStudy outcomes\\u003c/h2\\u003e \\u003cp\\u003eThe primary outcome was the inflection point of IDI for a CD. Baseline maternal demographics, clinical characteristics and neonatal and maternal outcomes following an attempted vaginal delivery of twins were compared between short and prolonged IDI as defined by the inflection point found. Secondary outcomes included the rate of placental abruption, chorioamnionitis, postpartum hemorrhage (PPH) (defined as hemoglobin drop\\u0026thinsp;\\u0026gt;\\u0026thinsp;3 gr/dL), need for blood transfusion, length of hospital stay and advanced perineal lacerations. In addition, the association between prolonged IDI (defined as IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes) and a composite of adverse maternal outcomes, including at least one of the following was assessed: placental abruption, PPH, need for blood transfusion, 3rd/4th-degree perineal laceration and puerperal fever\\u0026thinsp;\\u0026ge;\\u0026thinsp;38\\u0026deg;C. In addition, the rate of neonatal mortality, 5-minute Apgar score\\u0026thinsp;\\u0026lt;\\u0026thinsp;7, neonatal acidemia (defined as cord arterial pH\\u0026thinsp;\\u0026le;\\u0026thinsp;7.1), admission to the neonatal intensive care unit (NICU), and length of NICU stay were evaluated. Additionally, secondary maternal and neonatal outcomes of deliveries following short vs. prolonged IDI were compared based on the time interval associated with the highest sensitivity and specificity for a CD.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec7\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStatistical analysis\\u003c/h2\\u003e \\u003cp\\u003eSPSS v.28th (SPSS, Inc., Chicago, IL) was used for statistical analyses. The receiver operating characteristic (ROC) curve and Youden J statistics were used to determine the most predictive inflection point for CD. The highest J statistics represents the point where the sensitivity and specificity yield the optimum cutoff point. Following the determination of the optimum cutoff, we compared baseline characteristics and maternal and neonatal outcomes between the groups. The Chi-squared test or Fisher exact test was used to analyze categorical variables. The Mann-Whitney or the student's t-test was used to compare non-normally distributed and normally distributed continuous variables. All tests were two-sided and considered statistically significant at p value\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eDuring the study period, 499 women with twin gestation reached the second stage of labor. Thirty-eight women were excluded from the analysis due to intrauterine fetal death, major fetal abnormalities or delivery at a gestational age of \\u0026lt;\\u0026thinsp;24 weeks. Based on the ROC curve (AUC 0.838, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001) and the Youden J statistics, the IDI inflection point was 15 min (sensitivity \\u0026ndash; 80%; specificity \\u0026ndash; 75%), (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e, Table\\u0026nbsp;\\u003cspan refid=\\\"Tab1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e). A total of 461 women were included in the final analysis, 312 in the short IDI group (IDI\\u0026thinsp;\\u0026le;\\u0026thinsp;15 minutes) and 149 women in the prolonged IDI group (IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes) (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e).\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab1\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 1\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003e\\u0026ndash; IDI, sensitivity, specificity, and J statistic for CD\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"4\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIDI (minutes)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eSensitivity\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eSpecificity\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eJ - statistic\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1.000\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.288\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.288\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e10\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.933\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.582\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.516\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e15\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.800\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.747\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.547\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e20\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.567\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.838\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.404\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.467\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.893\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.360\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e30\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.333\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.930\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.264\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e35\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.267\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.947\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.213\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e40\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.167\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.965\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.132\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e45\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e0.133\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0.977\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.110\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"4\\\" nameend=\\\"c4\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eAbbreviations: IDI, intertwin delivery interval.\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eBaseline maternal demographics and clinical characteristics are presented in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e. Women in the prolonged IDI group were statistically older than women in the short IDI group (32.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;4.7 years vs. 31.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;4.7 years, p\\u0026thinsp;=\\u0026thinsp;0.03). All other baseline characteristics were similar between the groups. The mean IDI difference between the groups was 22 min (7.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;3.5 min vs. 29.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;20.3 min, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001).\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab2\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 2\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eMaternal Demographics and Clinical Characteristics\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"4\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eIntertwin interval\\u0026thinsp;\\u0026le;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;312)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eIntertwin\\u003c/p\\u003e \\u003cp\\u003einterval\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;149)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003ep\\u003c/em\\u003e value\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eMaternal age (years) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e31.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;4.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e32.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;4.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.03\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eBody mass index (kg/m\\u003csup\\u003e2\\u003c/sup\\u003e) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e30.3\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;12.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e30.7\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;4.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNulliparous, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e96 (30.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e56 (37.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.15\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eDichorionic \\u0026ndash; Diamniotic twins, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e253 (82.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e131 (88.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.11\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eInduction of labor, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e125 (32.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e24 (31.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.88\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eEpidural analgesia, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e269 (86.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e123 (83.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.30\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eGestational age at delivery (weeks) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e36.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;2.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e35.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;2.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.20\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e2nd stage of labor (minutes) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e53.1\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;67.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e53.0\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;65.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.80\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eBirthweight twin I (g) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003cp\\u003eBirthweight twin II (g) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003cp\\u003eDelta birthweight (g) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2397\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;523\\u003c/p\\u003e \\u003cp\\u003e2,360\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;496\\u003c/p\\u003e \\u003cp\\u003e-36.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;330.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2,352\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;572\\u003c/p\\u003e \\u003cp\\u003e2,379\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;573\\u003c/p\\u003e \\u003cp\\u003e27.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;397.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.30\\u003c/p\\u003e \\u003cp\\u003e0.69\\u003c/p\\u003e \\u003cp\\u003e0.11\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIntertwin delivery interval (minutes) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e7.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;3.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e29.2\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;20.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026lt;\\u0026thinsp;0.001\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eMaternal outcomes are presented in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab3\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e. Prolonged IDI was associated with increased CD rate (16.8% vs. 1.6%, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001), PPH (39.1% vs. 24.7% p\\u0026thinsp;=\\u0026thinsp;0.01), placental abruption (4% vs. 1%, p\\u0026thinsp;=\\u0026thinsp;0.03) and a composite adverse maternal outcome (30.2% vs. 19.9%, p\\u0026thinsp;=\\u0026thinsp;0.01). The rates of advanced perineal tears and chorioamnionitis were similar between the groups.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab3\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 3\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eMaternal Outcomes\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"4\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eIntertwin interval\\u0026thinsp;\\u0026le;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;312)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eIntertwin interval\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;149)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003eP\\u003c/em\\u003e-value\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eVaginal delivery of the 2nd twin, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e291 (93.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e113 (75.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\" morerows=\\\"2\\\" rowspan=\\\"3\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e\\u0026lt;\\u0026thinsp;0.001\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eVE of the 2nd twin, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e16 (5.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e11 (7.4)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCesarean delivery of the 2nd twin, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5 (1.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e25 (16.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eHospital stay (days) median\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.15\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003ePPH, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e44 (24.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e36 (39.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.01\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e3rd /4th -degree laceration, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1 (0.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1 (0.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.59\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eChorioamnionitis, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e12 (3.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e4 (2.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.52\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003ePlacental abruption, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e3 (1.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e6 (4.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.03\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eComposite adverse maternal outcomes*, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e62 (19.9)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e45 (30.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.01\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"4\\\" nameend=\\\"c4\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003e* Composite maternal outcomes include at least one of the following: placental abruption, postpartum hemorrhage, need for blood transfusion, 3rd /4th degree laceration, chorioamnionitis.\\u003c/p\\u003e \\u003cp\\u003eAbbreviations: VE, vacuum extraction; PPH, postpartum hemorrhage\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eNeonatal outcomes are presented in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab4\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e. Neonates in the prolonged IDI group were more likely to have neonatal acidemia and low 5-minute Apgar score (15.7% vs. 4.3%, P\\u0026thinsp;=\\u0026thinsp;0.01, 9.7% vs. 3.5%, P\\u0026thinsp;=\\u0026thinsp;0.008; respectively). A trend of a higher NICU admission rate was demonstrated in the prolonged IDI group (34.9% vs. 27.2%, P\\u0026thinsp;=\\u0026thinsp;0.09). Of note, the length of stay in NICU was similar between the groups.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab4\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 4\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eNeonatal outcomes of the second twin as a function of intertwin delivery interval\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"4\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eIntertwin interval\\u0026thinsp;\\u0026le;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;312)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eIntertwin interval\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes (n\\u0026thinsp;=\\u0026thinsp;149)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003ep\\u003c/em\\u003e value\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eApgar score at 5 min\\u0026thinsp;\\u0026le;\\u0026thinsp;7, n, (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11 (3.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e14 (9.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.008\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eAdmission to NICU, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e85 (27.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e52 (34.9)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.09\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNICU length of stay (days) mean\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;SD\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e8.9\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;14.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e10.6\\u0026thinsp;\\u0026plusmn;\\u0026thinsp;13.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.24\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eNeonatal mortality, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1 (0.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1. (0.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.59\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eArterial cord pH\\u0026thinsp;\\u0026le;\\u0026thinsp;7.1, n (%)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5 (4.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e8 (15.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003e0.01\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"4\\\" nameend=\\\"c4\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eAbbreviations: NICU, neonatal intensive care unit\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cdiv id=\\\"Sec10\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eMain findings\\u003c/h2\\u003e \\u003cp\\u003eThis study evaluated the impact of prolonged IDI on maternal and neonatal outcomes and the optimum cutoff point for CD. The findings correlated a prolonged IDI of \\u0026gt;\\u0026thinsp;15 minutes with a higher rate of CD, placental abruption, and PPH. Additionally, prolonged IDI was found to be linked to a higher rate of neonatal acidemia and lower 5-minute Apgar scores.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec11\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eComparison with existing literature\\u003c/h2\\u003e \\u003cp\\u003eThe presented cohorts suggested that a 15-min IDI had a 80% sensitivity and 75% specificity for CD, with a 16-fold increased risk for CD with prolonged IDI. These findings corroborate previous evidence that prolonged IDI increases the risk for CD of the second twin.[\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e] In particular, Stein et al.[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e], who conducted the largest study assessing neonatal outcomes following prolonged IDI, reported on a 12% CD rate in a prolonged IDI group compared to 0.7% in a short IDI group. Algeri et al.[\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] presented a 28% increase for emergency CD of the second twin, but used a cutoff of 30 min, which might have negatively impacted their results.\\u003c/p\\u003e \\u003cp\\u003eThe association between prolonged IDI and placental abruption observed here has been shown in previous studies as well.[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e] However, PPH, which may be associated with placental abruption, has not been reported before. Singleton pregnancies with a prolonged second stage are known to be associated with an increased rate of PPH, puerperal infection, and prolonged maternal hospital stay.[\\u003cspan citationid=\\\"CR20\\\" class=\\\"CitationRef\\\"\\u003e20\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e21\\u003c/span\\u003e] Similar to prolonged second stage in singleton pregnancies, we presented a higher rate of PPH when IDI was longer than 15 minutes, though we did not demonstrate any difference in puerperal infection or maternal hospital stay in those cases. The total duration of the second stage was similar between the groups and this suggest the PPH might result from the rapid uterine decompression or associated CD and not from the additional prolongation of the second stage of labor.\\u003c/p\\u003e \\u003cp\\u003eThe medical literature contains conflicting reports regarding the effect of prolonged IDI on neonatal acidemia and Apgar scores. Some are in agreement with the current work, showing higher neonatal acidemia and lower 5-min Apgar scores when IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 min[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e22\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR23\\\" class=\\\"CitationRef\\\"\\u003e23\\u003c/span\\u003e], while others present no correlation at all.[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e] In their evaluation of more than 4000 twin deliveries, Stein et al.[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e] found an increased rate of neonatal acidemia with IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;30 min and a correlation between low 5-min Apgar score and IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 min. These findings might have been related to an increased incidence of placental abruption, cord prolapse and fetal distress in the prolonged IDI group. In contrast to the present results, Rayburn et al.[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e], Algeri et al[\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]., and Schneuber et al.[\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e] found no correlation between prolonged IDI and a lower pH or Apgar scores. Of note, these studies were limited by small sample sizes, which might not have been adequately powered to detect this difference as a primary outcome. In addition, Schneuber et al.[\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e] excluded Cesarean and vaginal-assisted deliveries from their study, which likely contributed to their favorable Apgar and pH scores.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec12\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStrengths and limitations\\u003c/h2\\u003e \\u003cp\\u003eThe main strength of this study was its heterogenous population of low and high-risk women of various ethnicities and parities. In addition, the analysis included a large cohort of deliveries that occurred over a ten-year period.\\u003c/p\\u003e \\u003cp\\u003eIntrinsic limitations included the retrospective and single-center elements of the study and some data might be prone to observer and reporter bias.\\u003c/p\\u003e \\u003c/div\\u003e \"},{\"header\":\"Conclusions and Implications\",\"content\":\"\\u003cdiv id=\\\"Sec13\\\" class=\\\"Section2\\\"\\u003e \\u003cp\\u003eIn conclusion, this study suggested that the second twin should be delivered within a maximal 15-min gap from the first twin to reduce risk of adverse maternal outcomes and CD. Furthermore, IDI\\u0026thinsp;\\u0026gt;\\u0026thinsp;15 minutes was associated with neonatal adverse outcomes, including neonatal acidemia and low 5-minute Apgar score. These findings warrant prospective studies to evaluate which early interventions might be beneficial for both the mother and the neonate.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgments\\u003c/strong\\u003e: nothing to declare.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConflict of Interest:\\u0026nbsp;\\u003c/strong\\u003eThe authors report no conflict of interest. No financial support was received for this research.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval:\\u003c/strong\\u003e The study was approved by the hospital\\u0026apos;s IRB (IRB 0153-20-RMB).\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent to participate:\\u003c/strong\\u003e not applicable.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication:\\u003c/strong\\u003e not applicable.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and material:\\u003c/strong\\u003e The data that support the findings of this study are available from the corresponding author, N. J., upon reasonable request.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCode availability:\\u003c/strong\\u003e not applicable.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eSynopsis:\\u0026nbsp;\\u003c/strong\\u003eIntertwin delivery interval of more than 15 minutes is associated with adverse maternal outcomes, of adverse neonatal outcomes to the second twin.\\u003c/p\\u003e\\n\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eRobinson C, Chauhan SP. Intrapartum management of twins. Clin Obstet Gynecol. 2004;47:248\\u0026ndash;62. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1097/00003081-200403000-00025\\u003c/span\\u003e\\u003cspan address=\\\"10.1097/00003081-200403000-00025\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eMartin JA, Hamilton BE, Sutton PD, Ventura SJ, Mathews TJ, Osterman MJK. Births: final data for 2008. Natl Vital Stat Rep. 2010;59(1):3\\u0026ndash;71.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eNational Vital Statistics Reports Volume 72., Number 1 January 31, 2023 n.d.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eZafarmand MH, Goossens SMTA, Tajik P, Bossuyt PMM, Asztalos EV, Gardener GJ, et al. Planned Cesarean or planned vaginal delivery for twins: secondary analysis of randomized controlled trial. Ultrasound Obstet Gynecol. 2021;57:582\\u0026ndash;91. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1002/uog.21907\\u003c/span\\u003e\\u003cspan address=\\\"10.1002/uog.21907\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eSchmitz T, Korb D, Azria E, Garab\\u0026eacute;dian C, Rozenberg P, S\\u0026eacute;nat MV, et al. Perinatal outcome after planned vaginal delivery in monochorionic compared with dichorionic twin pregnancy. 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The effect of twin-to-twin delivery time intervals on neonatal outcome for second twins. BMC Pregnancy Childbirth. 2018;18:36. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1186/s12884-018-1668-6\\u003c/span\\u003e\\u003cspan address=\\\"10.1186/s12884-018-1668-6\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eStein W, Misselwitz B, Schmidt S. Twin-to-twin delivery time interval: influencing factors and effect on short-term outcome of the second twin. 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Birth. 2018;45:37\\u0026ndash;42. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1111/birt.12317\\u003c/span\\u003e\\u003cspan address=\\\"10.1111/birt.12317\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAlgeri P, Callegari C, Mastrolia SA, Brienza L, Vaglio Tessitore I, Paterlini G, et al. What is the effect of intertwin delivery interval on the outcome of the second twin delivered vaginally? 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Obstet Gynecol. 2001;98:1032\\u0026ndash;7. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1016/s0029-7844(01)01597-6\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/s0029-7844(01)01597-6\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eHirnle P, Franz HB, Sulkarnejewa E, Pfeiffer KH, Kiesel L. Caesarean section for the second twin after vaginal delivery of first. J Obstet Gynaecol. 2000;20:392\\u0026ndash;5. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1080/01443610050112048\\u003c/span\\u003e\\u003cspan address=\\\"10.1080/01443610050112048\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eCarroll MA, Yeomans ER. 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Am J Obstet Gynecol. 1987;156:52\\u0026ndash;6. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1016/0002-9378(87)90201-8\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/0002-9378(87)90201-8\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eMatta P, Turner J, Flatley C, Kumar S. Prolonged second stage of labour increases maternal morbidity but not neonatal morbidity. 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Intertwin time interval: how it affects the immediate neonatal outcome of the second twin. Am J Obstet Gynecol. 2005;192:1420\\u0026ndash;2. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1016/j.ajog.2005.02.079\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.ajog.2005.02.079\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eSuh YH, Park KH, Hong J-S, Yoon BH, Shim S-S, Park JS, et al. Relationship between Twin-to-twin Delivery Interval and Umbilical Artery Acid-base Status in the Second Twin. J Korean Med Sci. 2007;22:248\\u0026ndash;53. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.3346/jkms.2007.22.2.248\\u003c/span\\u003e\\u003cspan address=\\\"10.3346/jkms.2007.22.2.248\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAdam C, Allen AC, Baskett TF. Twin delivery: influence of the presentation and method of delivery on the second twin. Am J Obstet Gynecol. 1991;165:23\\u0026ndash;7. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003ehttps://doi.org/10.1016/0002-9378(91)90216-e\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/0002-9378(91)90216-e\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":true,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"reproductive-sciences\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"resc\",\"sideBox\":\"Learn more about [Reproductive Sciences](https://rd.springer.com/journal/43032)\",\"snPcode\":\"43032\",\"submissionUrl\":\"https://www.editorialmanager.com/resc/default2.aspx\",\"title\":\"Reproductive Sciences\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"Cutoff, Intertwin delivery interval, Maternal morbidity, Neonatal morbidity, Twin gestations, Vaginal delivery\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-3043327/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-3043327/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003ch2\\u003eObjective\\u003c/h2\\u003e \\u003cp\\u003eThe effect of prolonged intertwin delivery interval (IDI) is not well studied. This work aimed to assess the inflection point for Cesarean delivery (CD) and associated adverse maternal and neonatal outcomes.\\u003c/p\\u003e\\u003ch2\\u003eMethods\\u003c/h2\\u003e \\u003cp\\u003eThis was a retrospective cohort study at a single tertiary care center. The study included women with twin pregnancies in 2010\\u0026ndash;2019 who reached the second stage of labor, and assessed the most predictive cutoff for CD using Youden J statistic and compared adverse maternal and neonatal outcomes between short and prolonged intertwin delivery intervals.\\u003c/p\\u003e\\u003ch2\\u003eResults\\u003c/h2\\u003e \\u003cp\\u003eA total of 461 gravidas reached the second stage of labor and were included in the study. Using the ROC curve and Youden J statistic, the IDI cutoff was set at 15 min (80% sensitivity, 75% specificity, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001), with 312 women in the short and 149 in the prolonged IDI groups. Women in the prolonged IDI group were less likely to deliver the second twin vaginally (75.8% vs. 93.3%, p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001). Postpartum hemorrhage (PPH) (39.1% vs. 24.7%, p\\u0026thinsp;=\\u0026thinsp;0.01), and placental abruption (4% vs. 1%, p\\u0026thinsp;=\\u0026thinsp;0.03) were more likely to occur in the prolonged IDI group. An increased rate of neonatal acidemia and low 5-minute Apgar score were also found in the prolonged IDI group (15.7% vs. 4.3%, P\\u0026thinsp;=\\u0026thinsp;0.01, 9.7% vs. 3.5%, p\\u0026thinsp;=\\u0026thinsp;0.008; respectively).\\u003c/p\\u003e\\u003ch2\\u003eConclusion\\u003c/h2\\u003e \\u003cp\\u003eIDIs of more than 15 min are associated with increased risk of adverse maternal and neonatal outcomes. These findings should be used for counseling and managing twin pregnancies attempting vaginal delivery.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Exploring the Optimal Intertwin Delivery Interval for Vaginal Delivery\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2023-07-10 13:45:23\",\"doi\":\"10.21203/rs.3.rs-3043327/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"reviewerAgreed\",\"content\":\"\",\"date\":\"2023-07-08T16:38:38+00:00\",\"index\":0,\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2023-07-03T14:53:31+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2023-06-23T08:34:41+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Reproductive Sciences\",\"date\":\"2023-06-15T07:09:42+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"reproductive-sciences\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"resc\",\"sideBox\":\"Learn more about [Reproductive Sciences](https://rd.springer.com/journal/43032)\",\"snPcode\":\"43032\",\"submissionUrl\":\"https://www.editorialmanager.com/resc/default2.aspx\",\"title\":\"Reproductive Sciences\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"b1e425a0-25ab-42c5-9d60-af6f4b519485\",\"owner\":[],\"postedDate\":\"July 10th, 2023\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2024-03-04T15:12:17+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-3043327\",\"link\":\"https://doi.org/10.1007/s43032-024-01497-9\",\"journal\":{\"identity\":\"reproductive-sciences\",\"isVorOnly\":false,\"title\":\"Reproductive Sciences\"},\"publishedOn\":\"2024-02-29 15:01:23\",\"publishedOnDateReadable\":\"February 29th, 2024\"},\"versionCreatedAt\":\"2023-07-10 13:45:23\",\"video\":\"\",\"vorDoi\":\"10.1007/s43032-024-01497-9\",\"vorDoiUrl\":\"https://doi.org/10.1007/s43032-024-01497-9\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-3043327\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-3043327\",\"identity\":\"rs-3043327\",\"version\":[\"v1\"]},\"buildId\":\"_2-kVJe1T_tPrBINL-cwx\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}