Reproductive outcomes of IVF patients with unicornuate uteri

Impact of congenital uterine anomalies on obstetric and perinatal outcomes: systematic review and meta-analysis

Background

Congenital uterine anomalies (CUA) can be associated with impairments of early and late pregnancy events.

Objective

To assess the impact of CUA on reproductive outcomes in pregnancies conceived spontaneously or after assisted reproduction.

Materials and Methods

Systematic review and meta-analysis of cohort studies comparing patients with CUA versus women with normal uterus. A structured literature search was performed in leading scientific databases to identify prospective and retrospective studies. The Newcastle-Ottawa scale, adapted to AHRQ standards, was used to assess the risk of bias. Pooled odds ratios (OR) were calculated. Publication bias and statistical heterogeneity were assessed, and meta-regression was used to analyse the heterogeneity.

Main outcome measures

Miscarriage, ectopic pregnancy, placental abruption, term, and premature rupture of membranes (PROM), malpresentation at delivery, preterm delivery prior to 37, 34 and 32 weeks, caesarean delivery, intrauterine growth restriction/small for gestational age, foetal mortality and perinatal mortality.

Results

32 studies were included. CUAs increased significantly the risk of first/second trimester miscarriage (OR:1.54;95%CI:1.14-2.07), placental abruption (OR:5.04;3.60-7.04), PROM (OR:1.71;1.34-2.18), foetal malpresentation at delivery (OR:21.04;10.95-40.44), preterm birth (adjusted OR:4.34;3.59-5.21), a caesarean delivery (adjusted OR:7.69;4.17-14.29), intrauterine growth restriction/small for gestational age (adjusted OR:50;6.11-424), foetal mortality (OR:2.07;1.56-2.73) and perinatal mortality (OR:3.28;2.01-5.36).

Conclusions

CUA increases the risk of complications during pregnancy, delivery, and postpartum. Complications most frequent in CUA patients were preterm delivery, foetal malpresentation, and caesarean delivery.

What is new?

Bicornuate uterus was associated with the highest number of adverse outcomes, followed by didelphys, subseptate and septate uterus.

Impact of congenital uterine anomalies on reproductive outcomes of IVF/ICSI-embryo transfer: a retrospective study

OBJECTIVE

To study the impact of congenital uterine anomalies on reproductive outcomes after in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI)-embryo transfer (ET).

METHODS

A retrospective study including a total of 865women with congenital uterine anomalies and 865 age and admission time matched controls who underwent the first IVF/ICSI-ET cycle between January 2010 and December 2019 was conducted. Women with uterine anomalies were classified into canalization defect (complete septate uterus and subseptate uterus) and unification defect (unicornuate uterus, bicornuate uterus, and didelphus uterus) according to the processes of abnormal embryological development. Control women were selected by age (± 1.0 year) and admission time (± 6 months) matched with a 1:1 ratio. The reproductive outcomes were compared between women with uterine anomalies and the controls. The primary outcome was live birth; secondary outcomes were clinical pregnancy, ectopic pregnancy, preterm delivery, and spontaneous pregnancy loss.

RESULTS

Compared with women with a normal uterus, women with canalization defects were less likely to experience live birth [84/332 (25.3%) vs 128/332 (38.6%), RR: 0.647, 95% CI 0.513-0.815, P < 0.001]. They also had a lower clinical pregnancy rate [126/332 (38.0%) vs 206/332 (62.0%), RR: 0.829, 95% CI 0.690-0.997, P = 0.046] and experienced a higher first-trimester pregnancy loss rate [25/126 (19.8%) vs 11/206 (5.3%), RR: 2.716, 95% CI 1.393-5.295, P = 0.003]. Compared with women with a normal uterus, women with a unification defect were also less likely to experience live birth [132/533 (24.8%) vs 219/533 (41.1%), RR: 0.713, 95% CI 0.586-0.868, P = 0.001]. Women with a unification defect had lower clinical pregnancy rates [182/533 (34.1%) vs 263/533 (49.1%), RR: 0.813, 95% CI 0.695-0.952, P = 0.010] and increased first-trimester pregnancy loss [36/182 (19.8%) vs 20/263 (7.6%), RR: 3.288, 95% CI 1.776-6.085, P < 0.001]. While uterine anomaly seemed not increase the risk of preterm birth, ectopic pregnancy and second-trimester pregnancy loss.

CONCLUSIONS

Both canalization defects and unification defects were associated with lower fertility outcomes, including lower live birth rates, lower clinical pregnancy rates, and higher early miscarriage rates.

Reproductive outcomes of oocyte donation in patients with uterine Müllerian anomalies

OBJECTIVE

To evaluate live-birth rates per embryo transfer in patients with uterine Müllerian anomalies (UMAs). Secondary objectives were to compare reproductive outcomes between the normal uterus group, the different UMA types, and UMA subgroups with and without required surgery.

DESIGN

This retrospective study compared two cohorts, one with UMAs and other with normal uteri of our oocyte donation program at 12 Instituto Valenciano De Infertilidad/Reproductive Medicine Associates University affiliated clinics from January 2000 to 2020. The oocyte donation reduces confounding because of differences in embryo quality. The primary outcome was the live-birth rate per embryo transfer. Secondary outcomes included the rates of implantation, clinical pregnancy, miscarriage, and ongoing pregnancy. We calculated odds ratios with 95% confidence intervals.

PATIENTS

Infertile women undergoing oocyte donation with UMAs.

INTERVENTION

None.

MAIN OUTCOME MEASURES

The rates of implantation, clinical pregnancy, miscarriage, ongoing pregnancy, and live birth.

RESULTS

We analyzed 58,337 cycles of oocyte donation: 57,869 patients had no uterine malformation, and 468 women had UMAs. Compared with patients with normal uteri, patients with UMAs had lower rates of live births (36.67% [32.84-40.65] vs. 38.1% [95% confidence intervals {CI}: 37.82-38.42]) and ongoing pregnancy (39.74% [35.93-43.66] vs. 41.5% [41.24-41.83]). The miscarriage rate was higher in patients with UMAs (19.5% [16.55-22.85] vs. 16.6% [16.47-16.92]). Specifically, patients with a unicornuate uterus (n=29) had lower rates of implantation (24.07% [13.49-37.64] vs. 42.85% [95% CI: 42.6-43.09]), pregnancy (41.86% [27.01-57.87] vs. 59.51% [59.22-59.81]), ongoing pregnancy (16.67% [6.97-31.36] vs. 41.54% [41.24-41.83]), and live births (16.67% [6.97-31.36] vs. 38.12% [37.83-38.42]). In addition, patients with a partial septate uterus (n=91) had a higher miscarriage rate (26.50% [18.44-34.89] vs. 16.7% [16.47-16.92]). Compared with the normal uterus group, the live-birth rates were lower in the UMA without surgery group (33.09% [27.59-38.96] vs. 38.12% [37.83-38.42]).

CONCLUSION

Among patients who received embryos derived from donated oocytes, live birth and ongoing pregnancy rates were lower in patients with UMAs compared with patients with normal uteri. A higher miscarriage rate was found in patients with UMAs. Patients with a unicornuate uterus had worse reproductive outcomes. Our results show that the uterus is less competent in patients with UMAs.

TRIAL REGISTRATION

This study was registered at clinicaltrial.gov (NCT04571671).

Reproductive outcome in 326 women with unicornuate uterus

OBJECTIVES

To study the reproductive outcomes of women with a unicornuate uterus and compare them to those of women with no congenital uterine anomaly.

METHODS

This was a single-center, retrospective cohort study. Cases were women aged at least 16 years who were diagnosed with a unicornuate uterus on transvaginal/transrectal ultrasound between January 2008 and September 2021. Controls were women with no congenital uterine anomaly matched 1:1 by age and body mass index. The primary outcome was live-birth rate. Secondary outcomes were pregnancy loss (miscarriage, ectopic pregnancy, termination of pregnancy), preterm delivery, mode of delivery and concomitant gynecological abnormalities (endometriosis, adenomyosis, fibroids).

RESULTS

Included in the study were 326 cases and 326 controls. Women with a unicornuate uterus had a significantly lower live-birth rate (184/388 (47.4%) vs 229/396 (57.8%); P = 0.004) and higher rates of overall miscarriage (178/424 (42.0%) vs 155/465 (33.3%); adjusted odds ratio (aOR), 2.21 (95% CI, 1.42-3.42), P < 0.001), ectopic pregnancy (26/424 (6.1%) vs 11/465 (2.4%); aOR, 2.52 (95% CI, 1.22-5.22), P = 0.01), preterm delivery (45/184 (24.5%) vs 17/229 (7.4%); aOR, 3.04 (95% CI, 1.52-5.97), P = 0.001) and Cesarean delivery (116/184 (63.0%) vs 70/229 (30.6%); aOR, 2.54 (95% CI, 1.67-3.88), P < 0.001). Rudimentary-horn pregnancies accounted for 7/26 (26.9%) ectopic pregnancies in the study group. Women with a unicornuate uterus were more likely to have endometriosis (17.5% vs 10.7%; P = 0.018) and adenomyosis (26.7% vs 15.6%; P = 0.001), but were not more likely to have fibroids compared with controls. Women with a functional rudimentary horn were more likely to have pelvic endometriosis compared to those without (odds ratio, 2.4 (95% CI, 1.4-4.1), P = 0.002).

CONCLUSIONS

Pregnant women with a unicornuate uterus should be classified as high risk. Removal of a functional rudimentary horn should be discussed with the patient to prevent a rudimentary-horn ectopic pregnancy. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Impact of uterine malformations on pregnancy and neonatal outcomes of IVF/ICSI–frozen embryo transfer

STUDY QUESTION

What is the impact of uterine malformations on reproductive and neonatal outcomes of IVF/ICSI–frozen embryo transfer?

SUMMARY ANSWER

Unification defective uteri are associated with poorer neonatal outcomes including higher preterm delivery rate and lower birthweight, and septate uteri are associated with worse fertility outcomes including higher miscarriage and lower live birth rates (LBRs).

WHAT IS KNOWN ALREADY

Several studies have investigated the negative effects of uterine malformations on pregnancy outcomes. However, an all-round and definitive conclusion has not been reached yet owing to the relatively low incidence of the disease and the heterogeneity of study populations, especially among women undergoing ART.

STUDY DESIGN, SIZE, DURATION

This was a retrospective cohort study including 411 women with congenital uterine anomalies and 14 936 women with a normal uterus who underwent first frozen-thawed embryo transfer cycles of IVF/ICSI from July 2008 to August 2019. We compared reproductive outcomes.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Reproductive outcomes of women with uterine malformations were studied through three propensity score-matched comparisons (patients with bicorporeal uterus, septate uterus and hemi-uterus [bicorporeal, septate and hemi-uterus groups, respectively] along with corresponding control groups without uterine malformations). We also compared pregnancy and neonatal outcomes, and performed subgroup analysis addressing didelphus, bicornuate uteri and septate uteri before and after surgery independently.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to the matched control group, women with a bicorporeal uterus had a significantly lower LBR (24.4% versus 34.8%, odds ratio (OR) 0.61 [95% CI: 0.37, 1.00], P = 0.048). The incidence of miscarriage and preterm delivery was higher but not statistically significant (29.0% versus 18.1%, OR 1.85 [95% CI: 0.82, 4.19], P = 0.135; 22.6% versus 9.9%, OR 2.64 [95% CI: 1.07, 6.52], P = 0.063, respectively). In addition, the bicorporeal group had a significantly lower gestational age, higher caesarean rate and lower birthweight than bicorporeal control. Women with a septate uterus had comparable clinical pregnancy rates to controls (43.3% versus 49.9%, OR 0.77 [95% CI: 0.57, 1.04], P = 0.091), increased miscarriage rates (23.5% versus 13.0%, OR 2.05 [95% CI: 1.18, 3.58], P = 0.010) and lower LBRs (29.4% versus 42.2%, OR 0.57 [95% CI: 0.41, 0.79], P = 0.001). In both singleton and twins pregnancies, pregnancy and neonatal outcomes were comparable between women with a septate uterus and control. Women with a hemi-uterus had a tendency for lower clinical pregnancy rate (36.8% versus 42.3%, OR 0.80 [95% CI: 0.52, 1.21], P = 0.287) and LBR (29.8% versus 33.1%, OR 0.86 [95% CI: 0.55, 1.34], P = 0.502), compared to women without malformations. The incidences of miscarriage and preterm delivery, respectively, were 16.7% versus 16.6% (OR 1.01 [95% CI: 0.41, 2.47], P = 0.989), and 9.5% versus 11.4% (OR 0.82 [95% CI: 0.27, 2.51], P = 1) in women with a hemi-uterus as compared to control.

LIMITATIONS, REASONS FOR CAUTION

This was a single-centre, retrospective study in which neonatal data were extracted from parental questionnaires. The information on uteri septum type and surgery methods was poorly presented, with limited detail. In patients with uterine malformations, the number of babies with birth defects and twin pregnancies was relatively small, limiting the power of the study.

WIDER IMPLICATIONS OF THE FINDINGS

Compared to patients with a normal uterus, women with uterine malformation have poorer reproductive outcomes. Pregnant women with a uterine anomaly need to be managed as high-risk pregnancies and followed with appropriate obstetric review.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Ministry of Technology (2018YFC1003000), the Elite Team Project of Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (JY201801), Shanghai Sailing Program (21YF1423200) and the Fundamental Research Program Funding of Ninth People’s Hospital affiliated to Shanghai Jiao Tong University School of Medicine (JYZZ117). B.W.M. is supported by an NHMRC Investigatorgrant (GNT1176437). B.W.M. reports consultancy (with stock options) for ObsEva. B.W.M. has received research funding from Ferring and Merck. The authors declare no other competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Reproductive, Obstetric and Neonatal Outcomes in Women with Congenital Uterine Anomalies: A Systematic Review and Meta-Analysis

Congenital uterine anomalies (CUA) may influence reproductive performance, resulting in adverse pregnancy associated complications. This study aimed to assess the association of CUA subtypes with reproductive, obstetric, and perinatal outcomes. We performed a systematic search of the MEDLINE, EMBASE, and Cochrane libraries for studies comparing pregnancy outcomes between women with CUA and those with a normal uterus. The random effects model was used to estimate the odds ratios (ORs) with a 95% confidence interval (CI). Women with CUA had a lower rate of live births (OR 0.47; 95% CI 0.33-0.69), and a higher rate of first trimester miscarriage (OR, 1.79; 95% CI 1.34-2.4), second trimester miscarriage (OR 2.92; 95% CI 1.35-6.32), preterm birth (OR 2.98; 95% CI 2.43-3.65), malpresentation (OR 9.1; 95% CI 5.88-14.08), cesarean section (OR 2.87; 95% CI 1.56-5.26), and placental abruption (OR 3.12; 95% CI 1.58-6.18). Women with canalization defects appear to have the poorest reproductive performance during early pregnancy. However, unification defects were associated with obstetric and neonatal outcomes throughout the course of pregnancy. It may be beneficial for clinicians to advise on potential complications that may be increased depending on the type and severity of CUA.

Clinical outcomes analysis of infertile women with unicornuate uterus in IVF-ET

PURPOSE

To explore the pregnancy outcomes, and neonatal status, arising from embryo transfer in unicornual uterine infertility patients.

METHODS

We analyzed 2499 cycles of clinical data from in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) from 1st May 2016 to 1st May 2018 in the Reproductive Center of the Third Affiliated Hospital of Zhengzhou University, including 109 women with unicornuate uterus (the observation group) and 2390 women with normally shaped uterus (the control group).

RESULTS

There were no significant differences in embryo implantation rate, clinical pregnancy rate or miscarriage rate (41.88 % VS 42.36 %, P = 0.904; 48.62 % VS 55.94 %, P = 0.133; 11.01 % VS 8.99 %, P = 0.474) between the two groups. The live birth rate in the observation group was lower than that in the control group (35.78 % VS 45.82 %, P = 0.040). The fetal birth weight of the observation group was lower than that of the control group among single-born live births (3009.12 ± 430.59 g VS 3413.40 ± 492.25 g, P = 0.017), but the differences were not observed in the sex ratio at birth, premature birth rate, low birth weight infant (LBW) rate and macrosomia rate (P > 0.05). The fetal birth weight of the observation group was lower than that of the control group among twins live births (2480.00 ± 190.32 g VS 2606.02 ± 471.59 g), but the difference between the groups did not reach statistical significance (P > 0.05)．Logistic regression analysis showed that age, number of embryos transplanted and uterine morphology were independent influencing factors of live birth.

CONCLUSION

Compared with women with normal uterus, the live birth rate of women with unicornuate uterus is low, and the birth weight of newborns with single birth is reduced.

Effects of bicornuate uterus on pregnancy and obstetric outcomes of in vitro fertilization / intracytoplasmic sperm injection

OBJECTIVE

A bicornuate uterus results from failure of the Müllerian ducts to completely fuse. If patients with bicornuate uterus are diagnosed with infertility, they can conceive with help from in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). With few studies on the reproductive performances of bicornuate uterus following IVF/ICSI treatment, the aim of present study is to investigate whether a bicornuate uterus would affect pregnancy rates and obstetric outcomes of infertile women.

STUDY DESIGN

A retrospective cohort study contained 232 women (58 with bicornuate uterus and 174 with normal uterus) was conducted. Patient data for IVF/ICSI treatment and follow-up were collected and analyzed. Cumulative pregnancy rate and cumulative live birth rate after one complete assisted reproductive technology (ART) cycle were the primary outcomes.

RESULTS

Baseline characteristics were comparable between the bicornuate uterus group and the control group. Ovarian response to stimulation and embryological results were similar between the two groups. In fresh embryo transfer cycles, embryo implantation rate (32.7 % vs. 42.9 %, P = 0.176), biochemical pregnancy rate (54.1 % vs. 64.9 %, P = 0.236), and clinical pregnancy rate (45.9 % vs. 58.8 %, P = 0.172) did not differ significantly between the bicornuate uterus group and the control group. Live birth rate (40.5 % vs. 43.9 %, P = 0.723), term delivery rate (93.3 % vs. 90.0 %, P = 0.696), cesarean section rate (73.3 % vs. 76.0 %, P = 0.833), and newborn birth weight (3.35 ± 0.56 vs. 3.32 ± 0.51, P = 0.524) also did not differ significantly between the two groups. In frozen-thawed embryo transfer cycles, there were no significant differences in outcomes between the two groups. Upon completion of one IVF/ICSI cycle, cumulative pregnancy rate (59.6 % vs. 71.0 %, P = 0.112) and cumulative live birth rate (58.2 % vs. 64.8 %, P = 0.375) were similar between the two groups.

CONCLUSION

There were no significant differences in ovarian responses, pregnancy outcomes, and obstetric outcomes after IVF/ICSI treatment between women with bicornuate uterus and women with normal uterus. Bicornuate uterus had no significant negative effects on cumulative IVF/ICSI outcomes of infertile patients.

Laparoscopic metroplasty for unicornuate uterus with a functional noncommunicating rudimentary horn

OBJECTIVE

To evaluate the feasibility of laparoscopic metroplasty for the treatment of unicornuate uterus with a functional noncommunicating rudimentary horn.

METHODS

Laparoscopic metroplasty was performed in one patient using traditional laparoscopy and four patients using robot-assisted laparoscopy from December 2013 to December 2017 at the Obstetrics and Gynecology Hospital of Fudan University. The records of the five patients were analyzed retrospectively.

RESULTS

In all five patients the unicornuate uterus and functional noncommunicating rudimentary horn were unified into a single cavity without intraoperative or postoperative complications. Average operative time was 281 minutes (range, 204-330 minutes) and average blood loss was 180 mL (range, 100-300 mL). Postoperative hospital stay was 7 days (range, 5-11 days) and there was no re-admission. All patients were relieved of pain and had regular menstruation after surgery. Average follow-up time was 44 months (range, 22-70 months). One patient conceived by in vitro fertilization and embryo transfer 2 years after the operation and delivered twins by cesarean at 33 weeks.

CONCLUSION

Laparoscopic metroplasty, with or without robotic assistance, is an acceptable alternative to resection for a noncommunicating rudimentary horn with a functional endometrium.

Uterine size and volume are associated with higher live birth rate in patients undergoing assisted reproduction technology: A prospective cohort study

To investigate how uterine size and volume are associated with live birth rate in patients undergoing assisted reproduction technology.This prospective cohort study was conducted at the Reproductive Medicine Centre from January 2010 to May 2017. Multivariate binary logistic regression was used to evaluate the relations between uterine size, total volume, and live birth outcomes, after they were adjusted for the main influencing factors.A total of 7320 women of clinical pregnancy were enrolled. Compared with uterine lengths of 50 to 59 mm (referent), women with uterine lengths ≥60 mm had a lower live birth rate (RR = 1.541). Compared with uterine widths of ≥50 mm (referent), women with uterine widths <30 mm had a lower live birth rate (RR = 1.430). Compared with uterine anteroposterior diameters of <30 mm (referent), women with uterine anteroposterior diameters ≥50 mm had a lower live birth rate (RR = 1.636). Compared with uterine volumes of 30 to 49 mL (referent), women with volumes <30 mL and ≥70 mL had lower live birth rates (RR = 1.368 and 1.742, respectively).Our findings indicate that uterine sizes and volumes that were too large or too small reduced the live birth rate.

Reproductive outcomes in women with unicornuate uterus undergoing in vitro fertilization: a nested case-control retrospective study

BACKGROUND

Unicornuate uterus, a congenital uterine malformation resulting from unilateral maldevelopment of Mullerian duct, is more prevalent in women with infertility. Owing to relative rarity of the condition, the evidence on the associated reproductive outcomes is derived from small heterogeneous studies that report different clinical endpoints and often do not account for the anatomical variations of unicornuate uterus. The aim of this study was to evaluate the embryological and clinical outcomes following IVF-ICSI treatment in women with unicornuate uterus without rudimentary functional cavity (ESHRE-ESGE class IVb).

METHODS

Retrospective nested case-control study comprised 342 women with unicornuate uterus and 1026 matched controls who underwent IVF-ICSI cycles between October 2012 and October 2016. Cumulative live birth rate upon one complete IVF cycle, including transfers of all resulting embryos was considered as a primary outcome measure.

RESULTS

Baseline characteristics were comparable between the unicornuate uterus and control groups except for higher rate of primary infertility in unicornuate uterus. Ovarian response to stimulation did not differ between the groups. Transfer of day-3 embryos in fresh cycle resulted in lower clinical pregnancy rate (35.9% vs. 43.9%, p = 0.028) and live-birth rate (26.9% vs. 35.2%, p = 0.017) per transfer, but the difference was not observed when either cleavage frozen-thaw embryos or blastocysts were transferred. Implantation rate was lower and miscarriage rate was higher in women with unicornuate uterus but the difference between the groups did not reach statistical significance. Transfer of cleavage embryos resulted in significantly higher miscarriage rate and lower live-birth rate in fresh versus frozen-thaw cycles in each group, whereas fresh and frozen-thaw blastocyst embryos had comparable outcomes. Upon completion of one IVF-ICSI cycle, the cumulative pregnancy rate (53.1% vs. 65.7, p < 0.001) and cumulative live birth rate (42.4% vs. 54.6%, p < 0.001) were significantly lower in women with unicornuate uterus compared to those in women with normal uterus. Cumulative outcomes were superior when embryos were cultured to blastocyst stage.

CONCLUSIONS

Women with unicornuate uterus have lower clinical pregnancy and live birth rate after IVF-ICSI treatment compared to women with normal uterus. The treatment outcomes are improved with blastocyst culture, which warrants evaluation in prospective setting.

The impact of unicornuate uterus on perinatal outcomes after IVF/ICSI cycles: a matched retrospective cohort study

OBJECTIVE

To evaluate the impact of unicornuate uterus on perinatal outcomes after in vitro fertilization and/or intracytoplasmic sperm injection (IVF/ICSI) cycles.

METHODS

We performed a retrospective cohort study including 160 women with unicornuate uterus and 1:1 matched controls with normally shaped uterus. They received IVF/ICSI treatment during January 2009 and December 2011. The perinatal outcomes were followed up till December 2014.

RESULTS

There were no significant differences in pregnancy rate, clinical pregnancy rate or live birth rate (53.6 versus 52.7, 41.4 versus 43.5, 33.8% versus 31.8%) between unicornuate uterus group and controls. Their biochemical pregnancy rate (22.8 versus 17.5%) and miscarriage rate (16.0 versus 18.8%) were similar. No significant differences were identified in preterm birth rate (18.3 versus 11.8%), birthweight (3.24 ± 0.60 versus 3.33 ± 0.54 kg) or birth length (50.47 ± 2.33 versus 50.06 ± 2.40 cm) among the singletons. However, lower gestational age (35.56 ± 2.68 versus 36.71 ± 1.73, p = .019), higher preterm birth rate (55.0 versus 34.4%, p = .038), lower birthweight (2.33 ± 0.58 versus 2.69 ± 0.38 kg, p = .001), lower birth length (45.33 ± 2.46 versus 48.88 ± 2.06 cm, p = .000), as well as higher rate of very low birthweight (13.2% versus 0, p = .007) were found for the twins from unicornuate uterus group.

CONCLUSIONS

The results indicated unimpaired pregnancy and perinatal outcomes for women with unicornuate uterus conceiving one fetus. However, close attention should be paid to twin pregnancy in unicornuate uterus owing to increased risks of prematurity and low birthweight. Selected single embryo transfer is recommended for women with unicornuate uterus undergoing IVF/ICSI cycles.