Effect of Previous Chlamydia Trachomatis Infection on the Outcomes of IVF/ICSI Treatment: A retrospective study

Effect of Previous Chlamydia Trachomatis Infection on the Outcomes of IVF/ICSI Treatment: A retrospective 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 Effect of Previous Chlamydia Trachomatis Infection on the Outcomes of IVF/ICSI Treatment: A retrospective study Dan Zhang, Zengyan Wang, Xingyuan Hu, Chunguang Ma, Yuanlin Ma, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-885642/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Apr, 2022 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted 2 You are reading this latest preprint version Abstract Background: The impact of Chlamydia trachomatis infection (CT) on the outcomes of In-Vitro Fertilizition / Intracytoplasmic sperm injection (IVF/ICSI) has been controversial. Methods: This retrospective study investigated the effect of cured CT infection and the intervals between infection and the first embryo transfer on pregnancy outcomes in infertile patients undergoing IVF/ICSI. A total of 431 infertility women aged 20-38 years with or without Chlamydia trachomatis infection before fresh/ frozen embryo transfer were included. We subdivided the infected group into two subgroups for ≤ 3 months and > 3 months according to the different intervals between Chlamydia trachomatis positive testing and embryo transfer. The effect of chlamydia infection and the intervals between infection and embryo transfer on pregnancy outcomes was analyzed. Results: Our results revealed that implantation rate was significantly lower and the premature rupture of membranes (PROM) was higher in women with CT infection than non-infection. The multivariate logistic regression analysis adjusting for baseline characteristics showed no significant difference in embryo implantation between neither two groups nor two subgroups while patients in infection group have higher rate of PROM than those in control group. Conclusions: The study suggests that previous Chlamydia trachomatis infection would not impair embryo implantation but lead to high risk of PROM and the intervals between infection and embryo transfer would not impact the pregnancy outcomes of IVF/ICSI. Chlamydia trachomatis infection In vitro fertilization Intracytoplasmic sperm injection Pregnancy outcome Figures Figure 1 Figure 2 Background Genital chlamydia trachomatis (CT) infection is one of the most common sexually transmitted diseases throughout the world. Presenting as asymptomatic in most cases [ 1 ], chlamydial infections can cause infection for more than one year among up to 50% of the infected people if not treated in time [ 2 ], which can lead to a series of serious complications such as pelvic inflammatory disease [ 3 ], ectopic pregnancy, fecundity decline and even tubal obstruction [ 4 , 5 ]. Since the infection of CT has shown adverse impact on human reproductive capability, however, the impact of CT infection on IVF/ICSI among infertile patients has been controversial and previous studies have reached different conclusions. It was reported that CT affected not only the fallopian tubes which can lead to tubal factor infertility, but also other genital tract sites [ 6 – 9 ]. The presence of anti-Chlamydia antibodies or heat shock protein 60 (HSP 60) may contribute to autoimmune response and the persistent subclinical chlamydial infection, leading to adverse effects on pregnancy outcomes in IVF/ICSI cycles [ 8 – 10 ]. It has been suggested that abnormal immune induced by persistent CT infection might promote tubal damage and have impact on IVF/ICSI outcomes. On the other hand, some studies found that there was no significant difference in outcomes of IVF/ICSI between patients with CT infection and those without infection [ 11 – 14 ]. Furthermore, there were few reports on the optimal time for embryo transfer after cure of chlamydia infection. As a result, we conducted a retrospective cohort study to further explore the impact of CT infection and the intervals between infection and embryo transfer on IVF / ICSI outcomes. Methods 1. Study population In this retrospective study, all women had screened for Mycoplasma genitalium, Chlamydia, bacterial vaginosis and trichomonas vaginalis before entering IVF/ICSI. Women who tested CT positive before oocyte retrieval or frozen embryo transfer of IVF/ICSI cycles were included in the experimental group when the CT test turned negative after one standard treatment. Women who tested CT negative without female tubal factors were enrolled as the control group from June 2018 to January 2020 of the First Affiliated Hospital of Sun Yat-sen University. The timeline of diagnosis and IVC/ICSI stage of infected group shown in Figure1. The other inclusive criteria: (1) undergoing an IVF / ICSI program. (2) Age between 20 and 38 years. (3) BMI≤28 kg/m2. (4) Normal ovarian reserve (bFSH < 10IU/L). (5) Number of oocytes retrieved≥ 5. (6) Total number of oocytes retrieval cycles ≤ 3. (7) Endometrial thickness on hCG day or progesterone conversion day ≥7mm. The exclusion criteria: (1) Patients with intrauterine abnormalities, including: endometrial polyps or submucosal fibroids, history of uterine adhesiolysis, uterine malformation. (2) Patients with a history of recurrent spontaneous abortion (RSA), RSA was defined as three or more consecutive pregnancies loss (including biochemical pregnancy abortion and clinical pregnancy loss). (3) Three or more times of embryo transfer without clinical pregnancy. (4) Patients with hydrosalpinx. (5) Patients with uncontrolled hyperprolactinemia, hypothyroidism and severe medical or surgical diseases. The institutional ethical board of the First Affiliated Hospital of Sun Yat-sen University approved this retrospective study. Fig. 1 Timeline of Diagnosis and IVC/ICSI Stage of the Infected Group 2. CT Detection and Treatments All patients were required to detect CT before oocyte retrieval or frozen embryo transfer every 6 months in IVF/ICSI cycles. The specimens were cervical swabs detected chlamydial lipopolysaccharide (LPS) by enzyme immunoassay (EIA). Patients tested positive were treated with a 7-day regimen of azithromycin or doxycycline before IVF/ICSI according to the recommendations of the Center for Disease Control and Prevention [ 15 ]..Sexual partners of CT-positive patients were treated at the same time. Only when patients retested negative after completing therapy can they enter IVF/ICSI-ET or frozen embryo transfer cycles. 3. Ovarian stimulation Patients received the luteal-phase gonadotrophin-releasing hormone agonist or gonadotrophin antagonist protocols. Since the pituitary was adequately suppressed, or on the 2-3 day of menstruation, ovarian stimulation was induced with human menopausal gonadotrophin and recombinant FSH (Merck Serono) individualized. Human chorionic gonadotrophin (hCG) was injected when two or more dominant follicles reached 18 mm in diameter. Then we collected oocytes 36 hours after hCG injection. 4. Outcome measures An infertility investigation was performed in all couples. We collected and analyzed data of general characteristics, ovulation induction, embryonic development and pregnancy outcomes. The primary outcome was live-birth rates, the secondary outcomes were the embryo implantation rate, chemical pregnancy rate, ectopic pregnancy rate, abortion rate and clinical pregnancy rate. In order to investigate whether the interval between CT infection and embryo transfer had any effective on pregnancy outcomes, we further divided the infection group into two subgroups: ≤ 3 months and > 3 months according to the intervals between CT infection and embryo transfer. Data of two subgroups were also compared. 5. Statistical analysis The statistical analyses were performed by SPSS 24.0 software. Pearson's Chi square test was used to analyze differences between relative frequencies. Student's t-test and one-way ANOVA were used to compare continuous variables. P<0.05 was considered statistically significant. The multivariate logistic regression model was fitted to analyze the effect of CT infection and the intervals between CT infection and embryo transfer on live birth adjusting for the study variables (baseline characteristics, protocols, and transfer cycles) for live birth rate. Odds ratios or hazard ratios and 95% confidence intervals were calculated. A two-sided a level of 0.05 was considered as statistically significant. Results 1. Baseline Characteristics From June 2018 to January 2020, a total of 690 patients were tested positive for C. trachomatis during the inclusion period, of whom 129 couples were eligible and among 687 patients tested CT negative and undergoing ICSI only for male infertility, 302 were enrolled for this analysis (Fig. 1). Fig. 2 The recruitment process In the infection group, 88 couples underwent IVF, 37 underwent ICSI and 4 underwent IVF+ICSI. The fresh cycle of 74 couples in the infection group and 151 in the control group were cancelled and they underwent thawed embryo transfer (TET) later mainly for ovarian hyperstimulation syndrome (OHSS), elevated progesterone and endometrial factors. Cycle baseline characteristics were similar between CT positive and negative group, such as age, BMI, infertility duration and basic FSH, while the incidence of secondary infertility and previous ectopic pregnancy rate was higher in CT infection group than that in control group (Table.1). Table.1 Baseline Characteristics of the infection and control group Indexes Infection group (n=129) Control group (n=302) P Age (years) 30.82±3.80 30.85±3.65 0.939 BMI (kg/m2) 21.19±2.25 21.20±2.34 0.962 Infertility duration (years) 3.40±2.05 3.73±2.56 0.208 Basal FSH (IU/L) 5.35±1.38 5.52±1.40 0.237 Types of infertility (%) 0.028* Primary infertility 48.8(63/129) 60.3(182/302) Secondary infertility 51.2(66/129) 39.7(120/302) Previous ectopic pregnancy (%) 16.27(21/129) 1.98(6/302) <0.001* Continuous variables are presented as the mean ± SD There were no significant differences between two groups concerning initial dose of gonadotropins (Gn), days of Gn used, total dose of Gn, level of serum E 2 and endometrial thickness on the day of hCG injection, number of retrieved oocytes, blastocyst formation rate and type of embryo transfer, but infection group had lower good-quality embryo rate and embryo transfer numbers, higher blastocyst transfer rate (Table.2). Table.2 Parameters of Patients with and without C. trachomatis Infection Indexes Infection group (n=129) Control group (n=302) P Initial dose of Gn (IU) 210.48±58.38 201.44±55.42 0.175 Days of Gn used (IU) 10.69±2.39 10.07±1.73 0.060 Total dose of Gn (IU) 2279.70±961.29 2086.76±800.81 0.054 level of E 2 on hCG day (ng/ml) 3203.27±1244.91 2986.53±1271.71 0.157 Endometrial thickness (mm) 11.70±2.20 11.79±3.15 0.804 Numbers of oocytes retrieved 15.80±6.96 15.79±6.96 0.990 Good-quality embryo rate (%) 83.3(649/779) 86.5(1438/1662) 0.041* Blastocyst formation on Day 5 or 6(%) 63.3(584/922) 61.2(1217/1987) 0.282 Transferred embryo stage (%) 0.006* D3 53.5(69/129) 67.5(204/302) D5/6 46.5(60/129) 32.5(98/302) Type of embryo transfer (%) 0.161 TET 57.4(74/129) 50(151/302) Fresh cycle 42.6(55/129) 50(151/302) Number of transferred embryos (%) 0.003* 1 51.9(67/129) 36.4(110/302) 2 48.1(62/129) 63.6(192/302) 2. Pregnancy outcomes The implantation rate (28,2% vs 36.2%, P=0.046) and multiple pregnancies rate (9.8% vs 26.8%, P=0.013) were found significantly lower and the PROM rate (7.8% vs 0.7%, P=0.025) was higher in CT infection group comparing with the CT negative. No significant difference was found in the chemical pregnancy rate (48.1% vs 53.0%, P =0.349), abortion rate (21.6% vs 12.7%, P =0.127), clinical pregnancy rate (39.5% vs 47.0%, P =0.152), and ectopic pregnancy rate (2.0% vs 1.3%, P =0.709) between the two groups (Table.3). During pregnancy, seven patients developed hypertensive disorders of pregnancy, one developed hyperthyroidism in pregnancy, one suffered with placenta previa and one had low amniotic fluid in the control group, which are not statistically significant comparing to the infection group. The rate of gestational diabetes mellitus is slightly higher in the control group than the infection group. As for conditions of birth and delivery, the rates of abortion, live birth and premature birth and the average birth weight of newborn are similar in both groups. One patient in the control group was diagnosed pulmonary embolism in the postpartum period. There was one neonate with cryptorchidism, one with strephenopodia and one with gastroschisis in the control group and one in the infection group was born with congenital heart diseases. Table.3 Clinical Outcomes of Patients with and without C. trachomatis Infection Indexes Infection group (n=129) Control group (n=302) P Implantation rate (%) 28.2(55/195) 36.2(177/489) 0.046* Chemical pregnancy rate (%) 48.1(62/129) 53.0(160/302) 0.349 Clinical pregnancy rate (%) 39.5(51/129) 47.0(142/302) 0.152 Ectopic pregnancy rate (%) 2.0(1/51) 1.3(2/160) 0.709 Multiple pregnancies rate (%) 9.8(5/51) 26.8(38/142) 0.013* Gestational diabetes mellitus (%) 0.0(0/51) 9.9(14/142) 0.044* Hypertensive disorders of pregnancy (%) 0.0(0/51) 4.9(7/142) 0.239 Hyperthyroidism in pregnancy (%) 0.0(0/51) 0.7(1/142) 1.000 Placenta previa (%) 0.0(0/51) 0.7(1/142) 1.000 Premature rupture of membranes (%) 7.8(4/51) 0.7 (1/142) 0.025* Oligohydramnios (%) 0.0(0/51) 0.7(1/142) 1.000 Abortion rate (%) 21.6(11/51) 12.7(18/142) 0.127 Live birth rate (%) 30.2(39/129) 40.1(121/302) 0.053 Gestational age (w) 38.3±1.9 38.1±2.1 0.670 Premature birth rate (%) 20.5(8/39) 21.7(26/120) 0.879 Pulmonary embolism (%) 0.0(0/39) 0.8 (1/120) 1.000 The univariate logistic regression showed live birth rate was associated with age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E 2 , approach of fertilization and whether CT infection or not. After adjusting for these factors, significant difference was still found in the rate of premature rupture of membranes between two groups, while no difference was showed comparing other pregnancy outcomes. (Table.4). Table.4 Clinical Outcomes after Adjustment Indexes OR (95%CI) P Adjusted OR (95%CI) P Chemical pregnancy rate (%) 0.821(0.544,1.241) 0.350 1.058(0.486,2.302) 0.887 Clinical pregnancy rate (%) 0.737(0.485,1.120) 0.153 0.932 (0.434,1.999) 0.856 Abortion rate (%) 1.894(0.826,4.347) 0.132 0.703 (0.121,4.082) 0.695 Live birth rate (%) 0.648 (0.417,1.007) 0.054 0.897 (0.411,1.958) 0.786 Multiple pregnancies rate (%) 0.297(0.110,0.805) 0.017 0.174(0.21,1.474) 0.109 Premature rupture of membranes (%) 12.000(1.308,110.051) 0.028 206.675(5.103,8369.836) 0.005 Categorical variables are presented as percentage (their frequencies), OR and 95% CI. Chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate are additionally adjusted for age, BMI, bFSH and infertility factors, approach of fertilization, transferred embryo stage (D3, D5 or D6), Number of transferred embryos. Italic values represents statistical significance. 3. The pregnancy outcomes of different intervals between infection and embryo transfer According to previous study (Patton et al.,1994), the detection of antibody against CT may associate with the intervals from the end of treatment. Based on the findings above and the clinical experience, we further subdivided the infection group into two subgroups for ≤ 3 months and > 3 months, according to the different intervals between CT infection and embryo transfer. All patients in CT positive group were treated with a 7-days regimen and retested CT negative before transferring embryos. The characteristics and outcomes of the two subgroups were also compared (Table.5). Table.5 Characteristics and outcomes after IVF/ICSI-ET in the infected group Indexes ≤3 months (n=60) >3 months (n=69) P Age (years) 31.35±3.89 30.95±3.82 0.263 BMI (kg/m2) 21.32±2.31 21.01±2.39 0.455 Basal FSH (U/L) 5.48±1.44 5.26±1.34 0.385 Types of infertility (%) 0.061 Primary infertility 40 (24/60) 56.5 (39/69) Secondary infertility 60(36/60) 43.5 (30/69) Endometrial thickness (mm) 11.71±2.21 11.60±2.36 0.789 Approach of Fertilization (%) 0.979 IVF 68.3 (41/60) 68.1 (47/69) ICSI/IVF+ICSI 31.7 (19/60) 31.9 (22/69) Type of embryo transfer (%) 0.053 TET 48.3 (29/60) 65.2 (45/69) Fresh cycle 51.7 (31/60) 34.8 (24/69) Number of transferred embryos (%) 0.767 1 53.3 (32/60) 50.7 (35/69) 2 46.7 (28/60) 49.3 (34/69) Transferred embryo stage (%) 0.500 D3 56.7 (34/60) 50.7 (35/69) D5/6 43.3 (26/60) 49.3 (34/69) Good-quality embryo rate (%) 86.7 (284/328) 80.9 (365/451) 0.034* Blastocyst formation rate (%) 59.9 (240/400) 65.9 (344/522) 0.064 Chemical pregnancy rate (%) 38.3 (23/60) 50.7 (35/69) 0.158 Clinical pregnancy rate (%) 36.7(22/60) 42.0(29/69) 0.534 Multiple pregnancies rate (%) 0(0/22) 17.2(5/29) 0.115 Premature rupture of membranes (%) 4.5(1/22) 13.6(3/22) 0.600 Abortion rate (%) 22.7(5/22) 20.7(6/29) 1.000 Live birth rate (%) 28.3(17/60) 31.9(22/69) 0.661 Gestational age(w) 37.4±3.5 38.2±2.4 0.417 Premature birth rate (%) 13.6(3/22) 17.9(5/28) 0.988 Birth weight (g) 3082.9 2844.8 0.271 Macrosomia (%) 4.5 (1/22) 3.6(1/28) 1.000 Normal birth weight infant (%) 81.8(18/22) 75.0(21/28) 0.815 Low birth weight infant (%) 13.6(3/22) 10.7(3/28) 1.000 Very low birth weight infant (%) 0(0/22) 10.7(3/28) 0.325 Congenital malformation (%) 4.5(1/22) 0(0/28) 0.440 The baseline characteristics were similar and comparable. Patients with interval >3 months showed slightly lower good-quality embryo rate than those ≤3 months. Except for this, there were no significant differences in pregnancy outcomes between the subgroups. The univariate logistic regression showed live birth rate was associated with age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E 2 , approach of fertilization and whether CT infection or not. The multivariate logistic regression showed the live the birth rate can be affected by age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E 2 , approach of fertilization and whether CT infection or not, which is consistent with the findings above. No significant difference was found in the clinical outcomes after adjustment (Table.6). Table.6 Clinical Outcomes after Adjustment in the infected group Indexes OR (95%CI) P Adjusted OR (95%CI) p Chemical pregnancy rate (%) 1.656 (0.820,3.343) 0.158 1.533 (0.703,3.343) 0.282 Clinical pregnancy rate (%) 1.286 (0.624,2.684) 0.495 1.140 (0.519,2.502) 0.745 Abortion rate (%) 0.862 (0.168,2.772) 0.593 0.555 (0.121,2.541) 0.448 Live birth rate (%) 1.313 (0.603,2.856) 0.493 1.184 (0.531,2.731) 0.692 Categorical variables are presented as percentage (their frequencies), OR and 95% CI. Chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate are additionally adjusted for age, BMI, bFSH and infertility factors, approach of fertilization, transferred embryo stage (D3, D5 or D6), number of transferred embryos. Discussion As we all know, the ICSI cycles have similar pregnancy outcomes to the IVF cycles [ 21 ]. In this study, women who underwent ICSI-ET treatment without fallopian tube factors were included in our control group, so as to minimize the impact of fallopian tube problems probably caused by previous CT infection on the outcome of the control group. The risk of major birth defects after ICSI were not found in the control group [ 22 ]. The infection and control groups were comparable regarding demographic data, infertility duration, duration of stimulation, duration of treatment, E 2 level and endometrial thickness on the day of HCG administration. There was no statistically significant difference observed between the two groups regarding the mean number of oocytes retrieved per patient and blastocyst formation rate, but the mean number of embryos transferred per patient and good quality embryos rate were significantly lower while the rate of premature rupture of membranes was higher in infection group than in control group. It had suggested that adverse reproductive sequelae of ectopic pregnancy due to CT infection had been associated with antibody response to the chlamydial heat shock protein 60 (CHSP 60) [ 4 , 5 , 16 ]. In our infection group, infertile women combined with tubal factors had higher incidence of previous ectopic pregnancy than the control group without tubal factors. However, during our IVF/ICSI-ET treatment, CT infection did not increase the incidence of ectopic pregnancy significantly. We speculated the possible reason was that previous studies on the impact of CT on natural conception did not address whether CT is prescriptively treated and turned negative before pregnancy, and some are even found to be CT positive during pregnancy. While in this study, the patients started the treatment for IVF/ICSI-ET only when CT was prescriptive therapy and the cervical swab resulted negative for Chlamydia. The impacts of CT on the pregnancy outcomes in assisted reproductive technology (ART) are still controversial. Several researchers demonstrated negative effects of previous chlamydial infection. According to Witkin et al. [ 10 ], the prevalence of CHSP 60 antibodies induce an inflammatory reaction in the uterus that may impair embryo implantation. Pacchiarotti et al. [ 9 ] found the presence of anti-chlamydia antibodies in both the serum and follicular fluid reduced the number of mature oocytes in antibodies-positive group, leading to the poor IVF outcome. On the contrary, some studies demonstrated that previous CT infection does not affect pregnancy outcomes in IVF/ICSI (11-13,17). Claman et.al [ 18 ] showed no differences in pregnancy rates or outcomes in patients with and without serologic evidence of previous CT infection. Nevertheless, Serum antichlamydial antibodies do not correlate as well with cervical infection. When infected by CT in genital tract, the expression and distribution of different kind of antibodies are not synchronoused [ 7 ]. Therefore, the misclassification of chlamydia stages may account for the different impacts of CT on pregnancy outcomes. A global systematic review [ 19 ] demonstrates associations between chlamydia and several adverse pregnancy outcomes. But there are some limitations due to the substantial heterogeneity across studies and the confounding variables such as medical history. The possible impacts of the related factors on the results cannot be explained when quantifying the correlation. In addition, differences of study population, sample size, treatment and random error may also have certain impact on the result. Our results of multivariable regression analysis showed that CT infection was not significantly associated with lower chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate, which confirmed that previous CT infection is not a risk factor of adverse pregnant outcomes of IVF/ICSI. The rate of premature rupture of membranes was higher in infection group than in control group. The persistent subclinical chlamydial infection and the abnormal immune induced by previous CT infection may increase the concentration of polymorphonuclear leukocytes which is capable of altering the local tissue pH and thus perturbing lysosomal membranes in the adjacent chorioamnion and histological chorioamnionitis. The effect could lead to weaken membranes and hence membrane rupture [ 23 , 24 ]. According to previous study [ 20 ], the detection of antibody against CT may associate with the intervals from the end of treatment. Based on the findings above and the clinical experience, we further subdivided the infection group into two subgroups for ≤ 3 months and > 3 months. There was no differences between the subgroups, showing that the group >3 months interval between CT infection diagnosis and embryo transfer have similar outcomes in the IVF/ICSI to those ≤3 months. According to Hoenderboom et.al. [ 14 ], Women with previous CT infection have similar overall pregnancy rates as those tested negative but took longer to get pregnant possibly because of intratubal microdamage. Therefore, we suggested that the infection of CT without hydrosalpinx will not impair the ability of embryos implantation and development after their transfer to the uterus. However, the PROM rate showed higher in the infection group than the control group while no different was found between the subgroups. It suggested that longer time interval would not reduce the impact of CT infection on the risk of PROM. In this study, we formulated strict inclusion criteria, exclusion criteria and perform a multivariable logistic regression, which is conducive to eliminate the possible effects of general characteristics in the transplantation cycles. Compared with previous studies, we greatly controlled the possible confounders between the infection group and the control group. Subgroup stratification was performed in the infected group to analyze whether the time intervals between infection and embryo transfer had any effect on pregnancy outcomes. The results showed that prolonged interval did not increase implantation rate, clinical pregnancy rate, live birth rate, and did not reduce miscarriage rate when the interval >3 months verse ≤ 3 months. Our results suggest that there is no need to delay embryo transfer after cure of CT infection during the IVF/ICSI cycle. Conclusion This study demonstrates that cured CT infection without hydrosalpinx will not impair embryo implantation, clinical pregnancy and live birth but lead women at high risk of PROM during IVF/ICSI. Although CT infection does not significantly affect the live birth rate, it can result in an increased incidence of PROM, while extended interval between infection and embryo transfer will not decrease the risk of adverse outcomes, which may provide a good warning for clinical practice. There are still many deficiencies due to the limited sample size, testing technology and other reasons. We have not analyzed the long-term effects of previous CT infection to the infants. The effects of longer or shorter time intervals on pregnancy outcomes are unknown yet. Further study is warranted to confirm our proposal. Abbreviations IVF: In-Vitro Fertilization; ICSI: Intracytoplasmic sperm injection; Gn: Gonadotropins; CT: Chlamydia trachomatis; HSP 60: Heat shock protein 60; CHSP 60: Chlamydial heat shock protein 60 Declarations Ethics approval and consent to participate This study was performed under the approval of the local ethics committee of the First Affiliated Hospital of Sun Yat-Sen University and all patients provided signed written informed consent. Consent for publication Not Applicable. Availability of data and materials The datasets analyzed during the current study are not publicly available given the privacy of patient data and we plan to further analyze the data to dig up much more clinic information. But they are available from the corresponding author on reasonable request. Competing interests The authors declare that they have no competing interests. Funding This work was supported by Guangdong Provincial Key Laboratory of Reproductive Medicine. (Grant numbers 2012A061400003) Authors' contributions (I) Conception and design: YX, DZ; (II) Administrative support: YX; (III) Provision of study materials or patients: DZ, ZW; (IV) Collection and assembly of data: DZ, ZW, CM; (V) Data analysis and interpretation: DZ, XH, YM; (VI) Manuscript writing: DZ, XH; (VII) Final approval of manuscript: All authors. Acknowledgements Not applicable. References Low N. Screening programmes for chlamydial infection: when will we ever learn? BMJ. 2007;334(7596):725–8. Geisler WM. Duration of untreated, uncomplicated Chlamydia trachomatis genital infection and factors associated with chlamydia resolution: a review of human studies. J Infect Dis. 2010;201(Suppl 2):104–13. Davies B, Turner KME, Benfield T, et al. Pelvic inflammatory disease risk following negative results from chlamydia nucleic acid amplification tests (NAATs) versus non-NAATs in Denmark: A retrospective cohort. PLoS Med. 2018;15(1):e1002483. Menon S, Timms P, Allan JA, et al. 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Antibody to the Chlamydia trachomatis 60 kDa heat shock protein in follicular fluid and in vitro fertilization outcome. Am J Reprod Immunol. 2008;59(2):85–9. Pacchiarotti A, Sbracia M, Mohamed MA, et al. Autoimmune response to Chlamydia trachomatis infection and in vitro fertilization outcome. Fertil Steril. 2009;91(3):946–8. Witkin SS, Sultan KM, Neal GS, Jeremias J, Grifo JA, Rosenwaks Z. Unsuspected Chlamydia trachomatis infection and in vitro fertilization outcome. Am J Obstet Gynecol. 1994;171(5):1208–14. Spandorfer SD, Neuer A, LaVerda D, et al. Previously undetected Chlamydia trachomatis infection, immunity to heat shock proteins and tubal occlusion in women undergoing in-vitro fertilization. Hum Reprod. 1999;14(1):60–4. Xie QZ, Xu WM, Qi QR, Luo ZL, Dong L. Patients with cervical Ureaplasma Urealyticum and Chlamydia Trachomatis infection undergoing IVF/ICSI-ET: The need for new paradigm. J Huazhong Univ Sci Technolog Med Sci. 2016;36(5):716–22. Zhu Y, Yin B, Wu T, et al. Comparative study in infertile couples with and without Chlamydia trachomatis genital infection. Reprod Health. 2017;14(1):5. Hoenderboom BM, van Bergen JEAM, Dukers-Muijrers NHTM, et al. Pregnancies and Time to Pregnancy in Women With and Without a Previous Chlamydia trachomatis Infection. Sex Transm Dis. 2020;47(11):739–47. Workowski KA, Bolan GA. Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines, 2015 [published correction appears in MMWR Recomm Rep. 2015 Aug 28;64(33):924]. MMWR Recomm Rep. 2015;64(RR-03):1-137. Brunham RC, Peeling R, Maclean I, Kosseim ML, Paraskevas M. Chlamydia trachomatis-associated ectopic pregnancy: serologic and histologic correlates. J Infect Dis. 1992;165(6):1076–81. Gaudoin M, Rekha P, Morris A, Lynch J, Acharya U. Bacterial vaginosis and past chlamydial infection are strongly and independently associated with tubal infertility but do not affect in vitro fertilization success rates. Fertil Steril. 1999 Oct;72(4):730–2. Claman P, Amimi MN, Peeling RW, Toye B, Jessamine P. Does serologic evidence of remote Chlamydia trachomatis infection and its heat shock protein (CHSP 60) affect in vitro fertilization-embryo transfer outcome? Fertil Steril. 1996;65(1):146–9. Tang W, Mao J, Li KT, et al. Pregnancy and fertility-related adverse outcomes associated with Chlamydia trachomatis infection: a global systematic review and meta-analysis. Sex Transm Infect. 2020;96(5):322–9. Patton DL, Askienazy-Elbhar M, Henry-Suchet J, et al. Detection of Chlamydia trachomatis in fallopian tube tissue in women with postinfectious tubal infertility. Am J Obstet Gynecol. 1994;171(1):95–101. Calderón G, Belil I, Aran B, et al. Intracytoplasmic sperm injection versus conventional in-vitro fertilization: first results. Hum Reprod. 1995;10(11):2835–9. Hansen M, Kurinczuk JJ. et.al. The risk of major birth defects after intracytoplasmic sperm injection and in vitro fertilization. N Engl J Med. 2002;346(10):725–30. Kacerovsky M, Musilova I, Hornychova H, et al. Bedside assessment of amniotic fluid interleukin-6 in preterm prelabor rupture of membranes. Am J Obstet Gynecol. 2014;211(4):385. .e1-385.e3859 . Alger LS, Lovchik JC, Hebel JR, Blackmon LR, Crenshaw MC. The association of Chlamydia trachomatis, Neisseria gonorrhoeae, and group B streptococci with preterm rupture of the membranes and pregnancy outcome. Am J Obstet Gynecol. 1988;159(2):397–404. Cite Share Download PDF Status: Published Journal Publication published 10 Apr, 2022 Read the published version in BMC Pregnancy and Childbirth → Version 1 posted First submitted to journal 07 Feb, 2022 Editorial decision: Minor revision 05 Oct, 2021 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. 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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-885642","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":86760980,"identity":"1a39155c-c5f3-451b-b7a8-d01b21ef73f9","order_by":0,"name":"Dan Zhang","email":"","orcid":"","institution":"Sun Yat-sen University First Affiliated Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Dan","middleName":"","lastName":"Zhang","suffix":""},{"id":86760981,"identity":"d1884cdd-4b61-4ec8-a2d5-f4b533e50e53","order_by":1,"name":"Zengyan Wang","email":"","orcid":"","institution":"Sun Yat-sen University First Affiliated Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Zengyan","middleName":"","lastName":"Wang","suffix":""},{"id":86760982,"identity":"cf214489-3060-491e-9e3f-06591326d593","order_by":2,"name":"Xingyuan Hu","email":"","orcid":"","institution":"Sun Yat-sen University Zhongshan School of Medicine","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xingyuan","middleName":"","lastName":"Hu","suffix":""},{"id":86760983,"identity":"edcd9a28-3817-4b8e-a8fb-09151eda5ba8","order_by":3,"name":"Chunguang Ma","email":"","orcid":"","institution":"Sun Yat-sen University First Affiliated Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Chunguang","middleName":"","lastName":"Ma","suffix":""},{"id":86760984,"identity":"df652307-c55e-47ca-897a-e3d72b778833","order_by":4,"name":"Yuanlin Ma","email":"","orcid":"","institution":"Sun Yat-sen University First Affiliated Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yuanlin","middleName":"","lastName":"Ma","suffix":""},{"id":86760985,"identity":"59152146-2222-4e23-b73d-ed1e97a26d15","order_by":5,"name":"Yanwen Xu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDElEQVRIiWNgGAWjYDADfiA+8ADG4yFGi2QDUEsCSVoMDgAJorQY3Mgx/FzYZpNnfO3wQ6AtdYnzZyQwPnjbxiBvjss9M3KMpWe2pRWb3U4zAGo5nLjhRgKz4dw2BsOdDdi18EvkGEjzbjucuO12AkjLgcQNEgls0rxtDAlgp2IBbBI5xr95t/1P3Dw7/QPMYey/8WkB2mIGtAVouHQOyBbmxIYbCWzM+LRI9jwrs+b9l5w443ZOwYEEg8PGG848bJacc07CcAMOLQbHkzff5jljl9g/O33zhw8VdbLz25MPfnhTZiOPyxYGBg4DZBMYHBsYGBuALAlc6oGA/QEK1x6P0lEwCkbBKBihAACkYF/Ar2KbQwAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-6834-7009","institution":"Reproductive Medical Center, the First Affiliated Hospital of Sun Yat-sen","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Yanwen","middleName":"","lastName":"Xu","suffix":""}],"badges":[],"createdAt":"2021-09-08 10:35:23","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-885642/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-885642/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12884-022-04624-z","type":"published","date":"2022-04-10T08:48:20+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":18690629,"identity":"b9fb043d-ec3c-4c03-a033-28219357c7a7","added_by":"auto","created_at":"2022-02-28 15:12:17","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":34541,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTimeline of Diagnosis and IVC/ICSI Stage of the Infected Group\u003c/strong\u003e\u003c/p\u003e\u003cp\u003e\u003cbr\u003e\u003c/p\u003e","description":"","filename":"Fig.1TimelineofDiagnosisandIVCICSIStage.png","url":"https://assets-eu.researchsquare.com/files/rs-885642/v1/93a94cada027c8f422c26c55.png"},{"id":18690353,"identity":"ea50e7c3-2f16-4968-9df1-46fbfee1a191","added_by":"auto","created_at":"2022-02-28 15:09:17","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":34091,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eThe recruitment process\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.2Therecruitmentprocess.png","url":"https://assets-eu.researchsquare.com/files/rs-885642/v1/ac5a3a1e56c819203b530057.png"},{"id":20158936,"identity":"cf8f6f29-8319-468e-b202-68b0950c8e59","added_by":"auto","created_at":"2022-04-10 08:48:29","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":671877,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-885642/v1/e5843732-7ea8-478d-99a5-369e3332de4d.pdf"}],"financialInterests":"","formattedTitle":"Effect of Previous Chlamydia Trachomatis Infection on the Outcomes of IVF/ICSI Treatment: A retrospective study","fulltext":[{"header":"Background","content":"\u003cp\u003eGenital chlamydia trachomatis (CT) infection is one of the most common sexually transmitted diseases throughout the world. Presenting as asymptomatic in most cases [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], chlamydial infections can cause infection for more than one year among up to 50% of the infected people if not treated in time [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], which can lead to a series of serious complications such as pelvic inflammatory disease [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], ectopic pregnancy, fecundity decline and even tubal obstruction [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSince the infection of CT has shown adverse impact on human reproductive capability, however, the impact of CT infection on IVF/ICSI among infertile patients has been controversial and previous studies have reached different conclusions. It was reported that CT affected not only the fallopian tubes which can lead to tubal factor infertility, but also other genital tract sites [\u003cspan additionalcitationids=\"CR7 CR8\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The presence of anti-Chlamydia antibodies or heat shock protein 60 (HSP 60) may contribute to autoimmune response and the persistent subclinical chlamydial infection, leading to adverse effects on pregnancy outcomes in IVF/ICSI cycles [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. It has been suggested that abnormal immune induced by persistent CT infection might promote tubal damage and have impact on IVF/ICSI outcomes. On the other hand, some studies found that there was no significant difference in outcomes of IVF/ICSI between patients with CT infection and those without infection [\u003cspan additionalcitationids=\"CR12 CR13\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eFurthermore, there were few reports on the optimal time for embryo transfer after cure of chlamydia infection. As a result, we conducted a retrospective cohort study to further explore the impact of CT infection and the intervals between infection and embryo transfer on IVF / ICSI outcomes.\u003c/p\u003e"},{"header":"Methods","content":"\u003ch2\u003e1. Study population\u003c/h2\u003e\n\u003cp\u003eIn this retrospective study, all women had screened for Mycoplasma genitalium, Chlamydia, bacterial vaginosis and trichomonas vaginalis before entering IVF/ICSI. Women who tested CT positive before oocyte retrieval or frozen embryo transfer of IVF/ICSI cycles were included in the experimental group when the CT test turned negative after one standard treatment. Women who tested CT negative without female tubal factors were enrolled as the control group from June 2018 to January 2020 of the First Affiliated Hospital of Sun Yat-sen University. The timeline of diagnosis and IVC/ICSI stage of infected group shown in Figure1. The other inclusive criteria: (1) undergoing an IVF / ICSI program. (2) Age between 20 and 38 years. (3) BMI\u0026le;28 kg/m2. (4) Normal ovarian reserve (bFSH \u0026lt; 10IU/L). (5) Number of oocytes retrieved\u0026ge; 5. (6) Total number of oocytes retrieval cycles \u0026le; 3. (7) Endometrial thickness on hCG day or progesterone conversion day \u0026ge;7mm. The exclusion criteria: (1) Patients with intrauterine abnormalities, including: endometrial polyps or submucosal fibroids, history of uterine adhesiolysis, uterine malformation. (2) Patients with a history of recurrent spontaneous abortion (RSA), RSA was defined as three or more consecutive pregnancies loss (including biochemical pregnancy abortion and clinical pregnancy loss). (3) Three or more times of embryo transfer without clinical pregnancy. (4) Patients with hydrosalpinx. (5) Patients with uncontrolled hyperprolactinemia, hypothyroidism and severe medical or surgical diseases. The institutional ethical board of the First Affiliated Hospital of Sun Yat-sen University approved this retrospective study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFig.\u0026nbsp;1 Timeline of Diagnosis and IVC/ICSI Stage of the Infected Group\u003c/strong\u003e\u003c/p\u003e\n\u003ch2\u003e2. CT Detection and Treatments\u003c/h2\u003e\n\u003cp\u003eAll patients were required to detect CT before oocyte retrieval or frozen embryo transfer every 6 months in IVF/ICSI cycles. The specimens were cervical swabs detected chlamydial lipopolysaccharide (LPS) by enzyme immunoassay (EIA). Patients tested positive were treated with a 7-day regimen of azithromycin or doxycycline before IVF/ICSI according to the recommendations of the Center for Disease Control and Prevention [\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e]..Sexual partners of CT-positive patients were treated at the same time. Only when patients retested negative after completing therapy can they enter IVF/ICSI-ET or frozen embryo transfer cycles.\u003c/p\u003e\n\u003ch2\u003e3. Ovarian stimulation\u003c/h2\u003e\n\u003cp\u003ePatients received the luteal-phase gonadotrophin-releasing hormone agonist or gonadotrophin antagonist protocols. Since the pituitary was adequately suppressed, or on the 2-3 day of menstruation, ovarian stimulation was induced with human menopausal gonadotrophin and recombinant FSH (Merck Serono) individualized. Human chorionic gonadotrophin (hCG) was injected when two or more dominant follicles reached 18 mm in diameter. Then we collected oocytes 36 hours after hCG injection.\u003c/p\u003e\n\u003ch2\u003e4. Outcome measures\u003c/h2\u003e\n\u003cp\u003eAn infertility investigation was performed in all couples. We collected and analyzed data of general characteristics, ovulation induction, embryonic development and pregnancy outcomes. The primary outcome was live-birth rates, the secondary outcomes were the embryo implantation rate, chemical pregnancy rate, ectopic pregnancy rate, abortion rate and clinical pregnancy rate.\u003c/p\u003e\n\u003cp\u003eIn order to investigate whether the interval between CT infection and embryo transfer had any effective on pregnancy outcomes, we further divided the infection group into two subgroups: \u0026le; 3 months and \u0026gt; 3 months according to the intervals between CT infection and embryo transfer. Data of two subgroups were also compared.\u003c/p\u003e\n\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e\n\u003ch2\u003e5. Statistical analysis\u003c/h2\u003e\n\u003cp\u003eThe statistical analyses were performed by SPSS 24.0 software. Pearson's Chi square test was used to analyze differences between relative frequencies. Student's t-test and one-way ANOVA were used to compare continuous variables. P\u0026lt;0.05 was considered statistically significant. The multivariate logistic regression model was fitted to analyze the effect of CT infection and the intervals between CT infection and embryo transfer on live birth adjusting for the study variables (baseline characteristics, protocols, and transfer cycles) for live birth rate. Odds ratios or hazard ratios and 95% confidence intervals were calculated. A two-sided a level of 0.05 was considered as statistically significant.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Results","content":"\u003ch2\u003e1. Baseline Characteristics\u003c/h2\u003e\n\u003cp\u003eFrom June 2018 to January 2020, a total of 690 patients were tested positive for C. trachomatis during the inclusion period, of whom 129 couples were eligible and among 687 patients tested CT negative and undergoing ICSI only for male infertility, 302 were enrolled for this analysis (Fig.\u0026nbsp;1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFig.\u0026nbsp;2 The recruitment process\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the infection group, 88 couples underwent IVF, 37 underwent ICSI and 4 underwent IVF+ICSI. The fresh cycle of 74 couples in the infection group and 151 in the control group were cancelled and they underwent thawed embryo transfer (TET) later mainly for ovarian hyperstimulation syndrome (OHSS), elevated progesterone and endometrial factors.\u003c/p\u003e\n\u003cp\u003eCycle baseline characteristics were similar between CT positive and negative group, such as age, BMI, infertility duration and basic FSH, while the incidence of secondary infertility and previous ectopic pregnancy rate was higher in CT infection group than that in control group (Table.1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.1 Baseline Characteristics of the infection and control group\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Taba\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eInfection group\u003c/p\u003e\n\u003cp\u003e(n=129)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eControl group\u003c/p\u003e\n\u003cp\u003e(n=302)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAge (years)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e30.82\u0026plusmn;3.80\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e30.85\u0026plusmn;3.65\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.939\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBMI (kg/m2)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e21.19\u0026plusmn;2.25\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e21.20\u0026plusmn;2.34\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.962\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eInfertility duration (years)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3.40\u0026plusmn;2.05\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3.73\u0026plusmn;2.56\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.208\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBasal FSH (IU/L)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5.35\u0026plusmn;1.38\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5.52\u0026plusmn;1.40\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.237\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTypes of infertility (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.028*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePrimary infertility\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e48.8(63/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e60.3(182/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSecondary infertility\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e51.2(66/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e39.7(120/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePrevious ectopic pregnancy (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e16.27(21/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e1.98(6/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003ctfoot\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"4\"\u003eContinuous variables are presented as the mean \u0026plusmn; SD\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tfoot\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThere were no significant differences between two groups concerning initial dose of gonadotropins (Gn), days of Gn used, total dose of Gn, level of serum E\u003csub\u003e2\u003c/sub\u003e and endometrial thickness on the day of hCG injection, number of retrieved oocytes, blastocyst formation rate and type of embryo transfer, but infection group had lower good-quality embryo rate and embryo transfer numbers, higher blastocyst transfer rate (Table.2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.2 Parameters of Patients with and without C. trachomatis Infection\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabb\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eInfection group\u003c/p\u003e\n\u003cp\u003e(n=129)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eControl group\u003c/p\u003e\n\u003cp\u003e(n=302)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eInitial dose of Gn (IU)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e210.48\u0026plusmn;58.38\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e201.44\u0026plusmn;55.42\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.175\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eDays of Gn used (IU)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e10.69\u0026plusmn;2.39\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e10.07\u0026plusmn;1.73\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.060\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTotal dose of Gn (IU)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2279.70\u0026plusmn;961.29\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2086.76\u0026plusmn;800.81\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.054\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003elevel of E\u003csub\u003e2\u003c/sub\u003e on hCG day (ng/ml)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3203.27\u0026plusmn;1244.91\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2986.53\u0026plusmn;1271.71\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.157\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eEndometrial thickness (mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e11.70\u0026plusmn;2.20\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e11.79\u0026plusmn;3.15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.804\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNumbers of oocytes retrieved\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e15.80\u0026plusmn;6.96\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e15.79\u0026plusmn;6.96\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.990\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGood-quality embryo rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e83.3(649/779)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e86.5(1438/1662)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.041*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBlastocyst formation on Day 5 or 6(%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e63.3(584/922)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e61.2(1217/1987)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.282\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTransferred embryo stage (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.006*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eD3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e53.5(69/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e67.5(204/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eD5/6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e46.5(60/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e32.5(98/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eType of embryo transfer (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.161\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTET\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e57.4(74/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50(151/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eFresh cycle\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e42.6(55/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50(151/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNumber of transferred embryos (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.003*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e51.9(67/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e36.4(110/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e48.1(62/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e63.6(192/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003ch2\u003e2. Pregnancy outcomes\u003c/h2\u003e\n\u003cp\u003eThe implantation rate (28,2% vs 36.2%, P=0.046) and multiple pregnancies rate (9.8% vs 26.8%, P=0.013) were found significantly lower and the PROM rate (7.8% vs 0.7%, P=0.025) was higher in CT infection group comparing with the CT negative. No significant difference was found in the chemical pregnancy rate (48.1%\u003cem\u003evs\u003c/em\u003e 53.0%, \u003cem\u003eP\u003c/em\u003e=0.349), abortion rate (21.6% \u003cem\u003evs\u003c/em\u003e 12.7%, \u003cem\u003eP\u003c/em\u003e=0.127), clinical pregnancy rate (39.5%\u003cem\u003evs\u003c/em\u003e 47.0%, \u003cem\u003eP\u003c/em\u003e=0.152), and ectopic pregnancy rate (2.0% \u003cem\u003evs\u003c/em\u003e 1.3%, \u003cem\u003eP\u003c/em\u003e=0.709) between the two groups (Table.3).\u003c/p\u003e\n\u003cp\u003eDuring pregnancy, seven patients developed hypertensive disorders of pregnancy, one developed hyperthyroidism in pregnancy, one suffered with placenta previa and one had low amniotic fluid in the control group, which are not statistically significant comparing to the infection group. The rate of gestational diabetes mellitus is slightly higher in the control group than the infection group.\u003c/p\u003e\n\u003cp\u003eAs for conditions of birth and delivery, the rates of abortion, live birth and premature birth and the average birth weight of newborn are similar in both groups. One patient in the control group was diagnosed pulmonary embolism in the postpartum period. There was one neonate with cryptorchidism, one with strephenopodia and one with gastroschisis in the control group and one in the infection group was born with congenital heart diseases.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.3 Clinical Outcomes of Patients with and without C. trachomatis Infection\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabc\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eInfection group (n=129)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eControl group\u003c/p\u003e\n\u003cp\u003e(n=302)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eImplantation rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e28.2(55/195)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e36.2(177/489)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.046*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eChemical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e48.1(62/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e53.0(160/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.349\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eClinical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e39.5(51/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e47.0(142/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.152\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eEctopic pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.0(1/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.3(2/160)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.709\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMultiple pregnancies rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e9.8(5/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e26.8(38/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.013*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGestational diabetes mellitus (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e9.9(14/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.044*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHypertensive disorders of pregnancy (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e4.9(7/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.239\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHyperthyroidism in pregnancy (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.7(1/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePlacenta previa (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.7(1/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePremature rupture of membranes (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e7.8(4/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.7 (1/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.025*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eOligohydramnios (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.7(1/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAbortion rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e21.6(11/51)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e12.7(18/142)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.127\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLive birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e30.2(39/129)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e40.1(121/302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.053\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGestational age (w)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e38.3\u0026plusmn;1.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e38.1\u0026plusmn;2.1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.670\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePremature birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e20.5(8/39)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e21.7(26/120)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.879\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePulmonary embolism (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0(0/39)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.8 (1/120)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe univariate logistic regression showed live birth rate was associated with age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E\u003csub\u003e2\u003c/sub\u003e, approach of fertilization and whether CT infection or not. After adjusting for these factors, significant difference was still found in the rate of premature rupture of membranes between two groups, while no difference was showed comparing other pregnancy outcomes. (Table.4).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.4 Clinical Outcomes after Adjustment\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabd\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eOR (95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eAdjusted OR (95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eChemical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.821(0.544,1.241)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.350\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.058(0.486,2.302)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.887\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eClinical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.737(0.485,1.120)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.153\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.932 (0.434,1.999)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.856\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAbortion rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.894(0.826,4.347)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.132\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.703 (0.121,4.082)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.695\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLive birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.648 (0.417,1.007)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.054\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.897 (0.411,1.958)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.786\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMultiple pregnancies rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.297(0.110,0.805)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.017\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.174(0.21,1.474)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.109\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePremature rupture of membranes (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e12.000(1.308,110.051)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.028\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e206.675(5.103,8369.836)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.005\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003ctfoot\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"5\"\u003eCategorical variables are presented as percentage (their frequencies), OR and 95% CI. Chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate are additionally adjusted for age, BMI, bFSH and infertility factors, approach of fertilization, transferred embryo stage (D3, D5 or D6), Number of transferred embryos. Italic values represents statistical significance.\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tfoot\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003ch2\u003e3. The pregnancy outcomes of different intervals between infection and embryo transfer\u003c/h2\u003e\n\u003cp\u003eAccording to previous study (Patton et al.,1994), the detection of antibody against CT may associate with the intervals from the end of treatment. Based on the findings above and the clinical experience, we further subdivided the infection group into two subgroups for \u0026le; 3 months and \u0026gt; 3 months, according to the different intervals between CT infection and embryo transfer. All patients in CT positive group were treated with a 7-days regimen and retested CT negative before transferring embryos. The characteristics and outcomes of the two subgroups were also compared (Table.5).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.5 Characteristics and outcomes after IVF/ICSI-ET in the infected group\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabe\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e\u0026le;3 months\u003c/p\u003e\n\u003cp\u003e(n=60)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003e\u0026gt;3 months\u003c/p\u003e\n\u003cp\u003e(n=69)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAge (years)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e31.35\u0026plusmn;3.89\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e30.95\u0026plusmn;3.82\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.263\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBMI (kg/m2)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e21.32\u0026plusmn;2.31\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e21.01\u0026plusmn;2.39\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.455\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBasal FSH (U/L)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5.48\u0026plusmn;1.44\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e5.26\u0026plusmn;1.34\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.385\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTypes of infertility (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.061\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePrimary infertility\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e40 (24/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e56.5 (39/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSecondary infertility\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e60(36/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e43.5 (30/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eEndometrial thickness (mm)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e11.71\u0026plusmn;2.21\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e11.60\u0026plusmn;2.36\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.789\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eApproach of Fertilization (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.979\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eIVF\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e68.3 (41/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e68.1 (47/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eICSI/IVF+ICSI\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e31.7 (19/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e31.9 (22/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eType of embryo transfer (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.053\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTET\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e48.3 (29/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e65.2 (45/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eFresh cycle\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e51.7 (31/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e34.8 (24/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNumber of transferred embryos (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.767\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e53.3 (32/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50.7 (35/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e46.7 (28/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e49.3 (34/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTransferred embryo stage (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.500\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eD3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e56.7 (34/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50.7 (35/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eD5/6\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e43.3 (26/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e49.3 (34/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGood-quality embryo rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e86.7 (284/328)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e80.9 (365/451)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.034*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBlastocyst formation rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e59.9 (240/400)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e65.9 (344/522)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.064\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eChemical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e38.3 (23/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e50.7 (35/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.158\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eClinical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e36.7(22/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e42.0(29/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.534\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMultiple pregnancies rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0(0/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e17.2(5/29)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.115\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePremature rupture of membranes (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e4.5(1/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e13.6(3/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.600\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAbortion rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e22.7(5/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e20.7(6/29)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLive birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e28.3(17/60)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e31.9(22/69)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.661\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eGestational age(w)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e37.4\u0026plusmn;3.5\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e38.2\u0026plusmn;2.4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.417\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePremature birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e13.6(3/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e17.9(5/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.988\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eBirth weight (g)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3082.9\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e2844.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.271\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMacrosomia (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e4.5 (1/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e3.6(1/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNormal birth weight infant (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e81.8(18/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e75.0(21/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.815\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLow birth weight infant (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e13.6(3/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e10.7(3/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.000\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eVery low birth weight infant (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0(0/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e10.7(3/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.325\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eCongenital malformation (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e4.5(1/22)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0(0/28)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.440\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe baseline characteristics were similar and comparable. Patients with interval \u0026gt;3 months showed slightly lower good-quality embryo rate than those \u0026le;3 months. Except for this, there were no significant differences in pregnancy outcomes between the subgroups.\u003c/p\u003e\n\u003cp\u003eThe univariate logistic regression showed live birth rate was associated with age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E\u003csub\u003e2\u003c/sub\u003e, approach of fertilization and whether CT infection or not.\u003c/p\u003e\n\u003cp\u003eThe multivariate logistic regression showed the live the birth rate can be affected by age, BMI, infertility duration, basal FSH, initial dose of Gn, total dose of Gn, level of E\u003csub\u003e2\u003c/sub\u003e, approach of fertilization and whether CT infection or not, which is consistent with the findings above. No significant difference was found in the clinical outcomes after adjustment (Table.6).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable.6 Clinical Outcomes after Adjustment in the infected group\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003ctable id=\"Tabf\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eIndexes\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eOR (95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eP\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eAdjusted OR (95%CI)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003ep\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eChemical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.656 (0.820,3.343)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.158\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.533 (0.703,3.343)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.282\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eClinical pregnancy rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.286 (0.624,2.684)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.495\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.140 (0.519,2.502)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.745\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAbortion rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.862 (0.168,2.772)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.593\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.555 (0.121,2.541)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.448\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eLive birth rate (%)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.313 (0.603,2.856)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.493\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.184 (0.531,2.731)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.692\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003ctfoot\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"5\"\u003eCategorical variables are presented as percentage (their frequencies), OR and 95% CI. Chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate are additionally adjusted for age, BMI, bFSH and infertility factors, approach of fertilization, transferred embryo stage (D3, D5 or D6), number of transferred embryos.\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tfoot\u003e\n\u003c/table\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eAs we all know, the ICSI cycles have similar pregnancy outcomes to the IVF cycles [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. In this study, women who underwent ICSI-ET treatment without fallopian tube factors were included in our control group, so as to minimize the impact of fallopian tube problems probably caused by previous CT infection on the outcome of the control group. The risk of major birth defects after ICSI were not found in the control group [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. The infection and control groups were comparable regarding demographic data, infertility duration, duration of stimulation, duration of treatment, E\u003csub\u003e2\u003c/sub\u003e level and endometrial thickness on the day of HCG administration. There was no statistically significant difference observed between the two groups regarding the mean number of oocytes retrieved per patient and blastocyst formation rate, but the mean number of embryos transferred per patient and good quality embryos rate were significantly lower while the rate of premature rupture of membranes was higher in infection group than in control group.\u003c/p\u003e \u003cp\u003eIt had suggested that adverse reproductive sequelae of ectopic pregnancy due to CT infection had been associated with antibody response to the chlamydial heat shock protein 60 (CHSP 60) [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In our infection group, infertile women combined with tubal factors had higher incidence of previous ectopic pregnancy than the control group without tubal factors. However, during our IVF/ICSI-ET treatment, CT infection did not increase the incidence of ectopic pregnancy significantly. We speculated the possible reason was that previous studies on the impact of CT on natural conception did not address whether CT is prescriptively treated and turned negative before pregnancy, and some are even found to be CT positive during pregnancy. While in this study, the patients started the treatment for IVF/ICSI-ET only when CT was prescriptive therapy and the cervical swab resulted negative for Chlamydia.\u003c/p\u003e \u003cp\u003eThe impacts of CT on the pregnancy outcomes in assisted reproductive technology (ART) are still controversial. Several researchers demonstrated negative effects of previous chlamydial infection. According to Witkin et al. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], the prevalence of CHSP 60 antibodies induce an inflammatory reaction in the uterus that may impair embryo implantation. Pacchiarotti et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] found the presence of anti-chlamydia antibodies in both the serum and follicular fluid reduced the number of mature oocytes in antibodies-positive group, leading to the poor IVF outcome. On the contrary, some studies demonstrated that previous CT infection does not affect pregnancy outcomes in IVF/ICSI (11-13,17). Claman et.al [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] showed no differences in pregnancy rates or outcomes in patients with and without serologic evidence of previous CT infection. Nevertheless, Serum antichlamydial antibodies do not correlate as well with cervical infection. When infected by CT in genital tract, the expression and distribution of different kind of antibodies are not synchronoused [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Therefore, the misclassification of chlamydia stages may account for the different impacts of CT on pregnancy outcomes.\u003c/p\u003e \u003cp\u003eA global systematic review [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e] demonstrates associations between chlamydia and several adverse pregnancy outcomes. But there are some limitations due to the substantial heterogeneity across studies and the confounding variables such as medical history. The possible impacts of the related factors on the results cannot be explained when quantifying the correlation. In addition, differences of study population, sample size, treatment and random error may also have certain impact on the result. Our results of multivariable regression analysis showed that CT infection was not significantly associated with lower chemical pregnancy rate, clinical pregnancy rate, abortion rate and live birth rate, which confirmed that previous CT infection is not a risk factor of adverse pregnant outcomes of IVF/ICSI.\u003c/p\u003e \u003cp\u003eThe rate of premature rupture of membranes was higher in infection group than in control group. The persistent subclinical chlamydial infection and the abnormal immune induced by previous CT infection may increase the concentration of polymorphonuclear leukocytes which is capable of altering the local tissue pH and thus perturbing lysosomal membranes in the adjacent chorioamnion and histological chorioamnionitis. The effect could lead to weaken membranes and hence membrane rupture [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. According to previous study [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], the detection of antibody against CT may associate with the intervals from the end of treatment. Based on the findings above and the clinical experience, we further subdivided the infection group into two subgroups for \u0026le; 3 months and \u0026gt; 3 months. There was no differences between the subgroups, showing that the group \u0026gt;3 months interval between CT infection diagnosis and embryo transfer have similar outcomes in the IVF/ICSI to those \u0026le;3 months. According to Hoenderboom et.al. [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], Women with previous CT infection have similar overall pregnancy rates as those tested negative but took longer to get pregnant possibly because of intratubal microdamage. Therefore, we suggested that the infection of CT without hydrosalpinx will not impair the ability of embryos implantation and development after their transfer to the uterus. However, the PROM rate showed higher in the infection group than the control group while no different was found between the subgroups. It suggested that longer time interval would not reduce the impact of CT infection on the risk of PROM.\u003c/p\u003e \u003cp\u003eIn this study, we formulated strict inclusion criteria, exclusion criteria and perform a multivariable logistic regression, which is conducive to eliminate the possible effects of general characteristics in the transplantation cycles. Compared with previous studies, we greatly controlled the possible confounders between the infection group and the control group. Subgroup stratification was performed in the infected group to analyze whether the time intervals between infection and embryo transfer had any effect on pregnancy outcomes. The results showed that prolonged interval did not increase implantation rate, clinical pregnancy rate, live birth rate, and did not reduce miscarriage rate when the interval \u0026gt;3 months verse \u0026le; 3 months. Our results suggest that there is no need to delay embryo transfer after cure of CT infection during the IVF/ICSI cycle.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study demonstrates that cured CT infection without hydrosalpinx will not impair embryo implantation, clinical pregnancy and live birth but lead women at high risk of PROM during IVF/ICSI. Although CT infection does not significantly affect the live birth rate, it can result in an increased incidence of PROM, while extended interval between infection and embryo transfer will not decrease the risk of adverse outcomes, which may provide a good warning for clinical practice. There are still many deficiencies due to the limited sample size, testing technology and other reasons. We have not analyzed the long-term effects of previous CT infection to the infants. The effects of longer or shorter time intervals on pregnancy outcomes are unknown yet. Further study is warranted to confirm our proposal.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eIVF: In-Vitro Fertilization;\u003c/p\u003e\n\u003cp\u003eICSI: Intracytoplasmic sperm injection;\u003c/p\u003e\n\u003cp\u003eGn: Gonadotropins;\u003c/p\u003e\n\u003cp\u003eCT: Chlamydia trachomatis;\u003c/p\u003e\n\u003cp\u003eHSP 60: Heat shock protein 60;\u003c/p\u003e\n\u003cp\u003eCHSP 60: Chlamydial heat shock protein 60\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was performed under the approval of the local ethics committee of the First Affiliated Hospital of Sun Yat-Sen University and all patients provided signed written informed consent.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets analyzed during the current study are not publicly available given the privacy of patient data and we plan to further analyze the data to dig up much more clinic information. But they are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by\u0026nbsp;Guangdong Provincial Key Laboratory of Reproductive Medicine. (Grant numbers 2012A061400003)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e(I) Conception and design: YX, DZ; (II) Administrative support: YX; (III) Provision of study materials or patients: DZ, ZW; (IV) Collection and assembly of data: DZ, ZW, CM; (V) Data analysis and interpretation: DZ, XH, YM; (VI) Manuscript writing: DZ, XH; (VII) Final approval of manuscript: All authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLow N. Screening programmes for chlamydial infection: when will we ever learn? BMJ. 2007;334(7596):725\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGeisler WM. 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MMWR Recomm Rep. 2015;64(RR-03):1-137.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrunham RC, Peeling R, Maclean I, Kosseim ML, Paraskevas M. Chlamydia trachomatis-associated ectopic pregnancy: serologic and histologic correlates. J Infect Dis. 1992;165(6):1076\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGaudoin M, Rekha P, Morris A, Lynch J, Acharya U. Bacterial vaginosis and past chlamydial infection are strongly and independently associated with tubal infertility but do not affect in vitro fertilization success rates. Fertil Steril. 1999 Oct;72(4):730\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eClaman P, Amimi MN, Peeling RW, Toye B, Jessamine P. Does serologic evidence of remote Chlamydia trachomatis infection and its heat shock protein (CHSP 60) affect in vitro fertilization-embryo transfer outcome? Fertil Steril. 1996;65(1):146\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTang W, Mao J, Li KT, et al. Pregnancy and fertility-related adverse outcomes associated with Chlamydia trachomatis infection: a global systematic review and meta-analysis. Sex Transm Infect. 2020;96(5):322\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePatton DL, Askienazy-Elbhar M, Henry-Suchet J, et al. Detection of Chlamydia trachomatis in fallopian tube tissue in women with postinfectious tubal infertility. Am J Obstet Gynecol. 1994;171(1):95\u0026ndash;101.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCalder\u0026oacute;n G, Belil I, Aran B, et al. Intracytoplasmic sperm injection versus conventional in-vitro fertilization: first results. Hum Reprod. 1995;10(11):2835\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHansen M, Kurinczuk JJ. et.al. The risk of major birth defects after intracytoplasmic sperm injection and in vitro fertilization. N Engl J Med. 2002;346(10):725\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKacerovsky M, Musilova I, Hornychova H, et al. Bedside assessment of amniotic fluid interleukin-6 in preterm prelabor rupture of membranes. Am J Obstet Gynecol. 2014;211(4):385. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e.e1-385.e3859\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAlger LS, Lovchik JC, Hebel JR, Blackmon LR, Crenshaw MC. The association of Chlamydia trachomatis, Neisseria gonorrhoeae, and group B streptococci with preterm rupture of the membranes and pregnancy outcome. Am J Obstet Gynecol. 1988;159(2):397\u0026ndash;404.\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":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Chlamydia trachomatis infection, In vitro fertilization, Intracytoplasmic sperm injection, Pregnancy outcome","lastPublishedDoi":"10.21203/rs.3.rs-885642/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-885642/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eThe impact of Chlamydia trachomatis infection (CT) on the outcomes of In-Vitro Fertilizition / Intracytoplasmic sperm injection (IVF/ICSI) has been controversial. \u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This retrospective study investigated the effect of cured CT infection and the intervals between infection and the first embryo transfer on pregnancy outcomes in infertile patients undergoing IVF/ICSI. A total of 431 infertility women aged 20-38 years with or without Chlamydia trachomatis infection before fresh/ frozen embryo transfer were included. We subdivided the infected group into two subgroups for ≤ 3 months and \u0026gt; 3 months according to the different intervals between Chlamydia trachomatis positive testing and embryo transfer. The effect of chlamydia infection and the intervals between infection and embryo transfer on pregnancy outcomes was analyzed.\u003cstrong\u003e \u003c/strong\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eOur results revealed that implantation rate was significantly lower and the premature rupture of membranes (PROM) was higher in women with CT infection than non-infection. The multivariate logistic regression analysis adjusting for baseline characteristics showed no significant difference in embryo implantation between neither two groups nor two subgroups while patients in infection group have higher rate of PROM than those in control group.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e The study suggests that previous Chlamydia trachomatis infection would not impair embryo implantation but lead to high risk of PROM and the intervals between infection and embryo transfer would not impact the pregnancy outcomes of IVF/ICSI.\u003c/p\u003e","manuscriptTitle":"Effect of Previous Chlamydia Trachomatis Infection on the Outcomes of IVF/ICSI Treatment: A retrospective study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-02-28 15:09:16","doi":"10.21203/rs.3.rs-885642/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"submitted","content":"BMC Pregnancy and Childbirth","date":"2022-02-07T09:44:10+00:00","index":"","fulltext":""},{"type":"decision","content":"Minor revision","date":"2021-10-05T14:11:51+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"18c3e5c8-05e4-4b36-8165-890b66d42371","owner":[],"postedDate":"February 28th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2022-04-10T08:48:20+00:00","versionOfRecord":{"articleIdentity":"rs-885642","link":"https://doi.org/10.1186/s12884-022-04624-z","journal":{"identity":"bmc-pregnancy-and-childbirth","isVorOnly":false,"title":"BMC Pregnancy and Childbirth"},"publishedOn":"2022-04-10 08:48:20","publishedOnDateReadable":"April 10th, 2022"},"versionCreatedAt":"2022-02-28 15:09:16","video":"","vorDoi":"10.1186/s12884-022-04624-z","vorDoiUrl":"https://doi.org/10.1186/s12884-022-04624-z","workflowStages":[]},"version":"v1","identity":"rs-885642","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-885642","identity":"rs-885642","version":["v1"]},"buildId":"-HB7Z8yhvgn0wM9Nzuekk","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}