P-782 Are pregnancy complications associated with the method of conception in female same-sex couples? Results of a retrospective, matched cohort study comparing ROPA and IUI
Authors: Moeykens M , Aktoz F , Loreti S , Darici E , Roelens C , Tournaye H , De Munck N , Blockeel C , Mackens S 
Published: July 2024

Abstract

Study question
Are pregnancies in female same-sex couples at a higher risk when using reception of oocytes from partner (ROPA) compared to those following intrauterine insemination (IUI)?

Summary answer
In female same-sex couples, pregnancies following ROPA demonstrated a higher incidence of preterm birth and first-trimester bleeding.

What is known already
Reception of Oocytes from PArtner (ROPA) enables both partners to contribute biologically to the desired pregnancy. However, oocyte donation, often performed in case of (premature) ovarian failure, is associated with an increased risk of hypertensive disorders of pregnancy/preeclampsia. Female same-sex couples typically comprising healthy, young women without underlying subfertility problems, are a priori at low absolute risk for pregnancy complications. Few studies have investigated the incidence of pregnancy complications and/or obstetrical outcomes in this specific group of women. Further insights and formal data could guide clinicians and patients in making informed decisions regarding the preferred method of conception.

Study design, size, duration
A retrospective, single-center, matched cohort study was performed including 577 unique female same-sex couples using donor semen who became pregnant after reproductive treatment (88 pregnancies following ROPA and 489 following IUI). None of the patients who opted for ROPA had (failed) IUI before. The study covered the period from January 2015 to January 2023.

Participants/materials, setting, methods
Pregnancies following ROPA were matched with pregnancies following IUI for age (+/-4 years), BMI (+/-4 kg/m2), parity (nulliparous vs multiparous) and date of embryo transfer/IUI (+/-1year) in a 1:1 ratio. Statistical Package for Social Sciences (SPSS) v26.0 was used for statistical analysis. Kolmogorov-Smirnov test was used to evaluate the normal distribution of continuous variables. Normally distributed data were analyzed with the student t-test and categorical variables were analyzed with the chi-square test.

Main results and the role of chance
After matching, 154 pregnancies (77 ROPA versus 77 IUI) were eligible for the study. Age (mean age 31.4±4.0 for ROPA versus 31.2±4.3 years for IUI, p = 0.48) and BMI (24.5±3.9 kg/m2 versus 25.2±4.4 kg/m2, for respectively ROPA versus IUI, p = 0.32) were comparable between groups after matching. Two ROPA pregnancies were excluded from further analysis due to elective termination of pregnancy (radiusaplasia and trisomy 21). Both groups experienced two stillbirths (two unexplained mors in utero, one chorioamnionitis and one intrapartum death). No significant difference in hypertensive disorders of pregnancy (HDP) (10.7% (8/75) versus 13.7% (10/73) for ROPA and IUI respectively, p = 0.53) or preeclampsia rates (11.0% (8/73) and 6.7% (5/75) for ROPA and IUI respectively, p = 0.33) was observed. ROPA-associated preeclampsia cases were often preterm (&lt;37weeks’ gestation) compared to IUI (5/8 versus 1/5). ROPA pregnancies had a higher incidence of preterm birth (15.1% vs 1.3%,p&lt;0.002) and first trimester bleeding was significantly more frequent (12.3% vs 0%,p&lt;0.001). No statistically significant differences were observed between groups in neonatal weight, fetal structural malformations and cesarean section delivery rates.

Limitations, reasons for caution
The study is limited by its retrospective design and inherent bias. Despite reducing the sample size, matching enhanced study robustness. Recognized risk factors for hypertensive disorder of pregnancy, like the use of donor sperm, may mitigate differences associated with conception methods in this population.

Wider implications of the findings
The study points out potentially increased obstetrical risks following ROPA. These data are crucial to counsel and guide female same-sex couples in their decision regarding the method of conception. The risk of hypertensive disorders of pregnancy, specifically preterm preeclampsia, associated with ROPA warrants further attention, urging larger prospective studies.

Trial registration number
not applicable