P-295 Impact of septate uteri on pregnancy and neonatal outcomes of IVF/ICSI–frozen embryo transfer

Study question What is the impact of septate uteri on reproductive and neonatal outcomes of IVF/ICSI–frozen embryotransfer? Summary answer septate uteri are associated with lower birthweight and worse fertility outcomes including lower Intrauterine implantation rate and lower live birth rates. What is known already Several studies have investigated the negative effects of septate uteri 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 theheterogeneity of study populations, especially among women undergoing ART. Study design, size, duration This was a retrospective cohort study including 149 women with septate uteri and 13921 women with a normal uterus who underwent first frozen-thawed embryo transfer cycles of IVF/ICSI from january 2016 to December 2022. We compared reproductive outcomes. Participants/materials, setting, methods Reproductive outcomes of women with septate uteri were studied through propensity score-matched comparisons (patients with septate uterus respectively along with corresponding control group without uterine malformations). We also comparedpregnancy and neonatal outcomes. Main results and the role of chance Compared to the matched control group, women with septate uterus had asignificantly lower LBR(37.58% versus 50.56%, odds ratio (OR) 1.698 [95% CI: 1.161, 2.484], P = 0.006) and Intrauterine implantation rate(36.31% versus 45.67%, odds ratio (OR) 1.474 [95% CI: 1.06, 2.06], P = 0.021) Limitations, reasons for caution This was a single-centre, retrospective study in which neonatal data were extracted fromparental questionnaires. In patientswith uterine malformations, the number of babies with birth defects and twin pregnancies was relatively small, limiting the power of thestudy. Wider implications of the findings Compared to patients with a normal uterus, women with septate uterus have poorer reproductive outcomes. Pregnant women with a septate uterus need to be managed as high-risk pregnancies and followed withappropriate obstetric review. Trial registration number not applicable