The effect of unicornuate uterus on reproductive outcomes in infertile patients.

Objective: Unicornuate uterus, which is a rare congenital anomaly, has been associated with obstetric and perinatal complications. The aim of this study is to evaluate the reproductive outcomes of patients with unicornuate uterus, and also to compare them with outcomes of infertile patients without a Müllerian anomaly.

Methods: Retrospective analyses of the data of 18-40 year old infertile patients with unicornuate uterus diagnosed in between January 2012 and December 2022, and a control group with the same number of patients, with age and infertility durations matched were performed. Demographic data, cycle parameters and reproductive outcomes of the unicornuate uterus and control groups were compared.

Results: A total of 75 patients with unicornuate uterus and a control group of 75 infertile patients without a Müllerian anomaly were included in the study. Totally, 116 and 91 pregnancies were achieved at unicornuate uterus and the control groups, respectively. Ectopic pregnancy rates (10.3 % vs 2.2 %, OR = 5.53, 95 %CI [1.17-26.21]) and malpresentation rates (29 % vs 0 %, OR = 1.40, 95 %CI [1.12-1.76]) were significantly higher and newborn birth weights in singleton pregnancies were significantly lower in the unicornuate group (3000 g vs 3455 g, p = 0.005). No significant difference was found in other obstetric parameters.

Conclusion: Unicornuate uterus constitutes a small portion of all congenital uterine anomalies. Although increased ectopic pregnancy and malpresentation rates with diminished birth weights were found in the unicornuate group in our study, live birth rates and preterm deliveries did not differ significantly between the two groups. However, patients should be counseled on this issue both during the reproductive treatment process and during pregnancy, and should be followed closely.