Pregnancy outcomes and cervical competence after cervical unification in U2bC2V1 (complete uterine septum with duplicated cervix and vaginal septum): a ten-year single center cohort

Complete uterine septum with duplicated cervix and longitudinal vaginal septum (U2bC2V1) is a rare Mullerian anomaly associated with adverse reproductive outcomes. The impact of cervical unification on subsequent cervical competence and pregnancy management remains uncertain. This study evaluated pregnancy outcomes following cervical unification, with particular emphasis on cervical cerclage management. In this longitudinal cohort study, medical records of women diagnosed with U2bC2V1 at ROYAN Institute, Tehran, Iran, between 2012 and 2022 were reviewed. Seventy-one women who underwent hysteroscopic metroplasty, cervical unification, and vaginal septum resection were included. Pregnancy outcomes were evaluated after surgery. To reduce the influence of major independent risk factors for preterm birth, twin pregnancies and pregnancies complicated by major obstetric disorders were excluded from the comparative analysis. Outcomes were descriptively compared between women who underwent ultrasound-indicated cerclage and those managed without cerclage. Among 71 women, 56 (78.9%) achieved pregnancy, including 41 spontaneous conceptions and 15 pregnancies following assisted reproductive technologies. Fifty-one pregnancies progressed beyond the first trimester. After exclusion of pregnancies with established risk factors for preterm birth, 41 singleton pregnancies were analyzed; 24 women underwent ultrasound-indicated cerclage and 17 did not. Women requiring cerclage were significantly older than those who did not (mean difference 3.78 years, 95% CI: 0.81–6.74; P = 0.014). No significant differences were observed between groups regarding BMI (95% CI: −5.05 to 2.72; P = 0.539), infertility history ( P = 0.896), previous miscarriage history, ectopic pregnancy, intrauterine fetal demise, prior preterm birth, or repeat hysteroscopy (all P > 0.05). Furthermore, rates of second-trimester pregnancy loss ( P = 0.629), preterm birth before 37 weeks ( P = 0.512), preterm birth before 32 weeks ( P = 0.802), live birth ( P = 0.482), and low birth weight ( P = 0.560) were comparable between groups. In this observational cohort, pregnancy outcomes were comparable between women who underwent ultrasound-indicated cerclage and those who did not require cerclage during serial cervical-length surveillance. Because the comparison groups differed in baseline risk by design, these findings should be interpreted as descriptive rather than causal. Nevertheless, serial cervical-length surveillance may represent an appropriate management strategy following cervical unification. Prospective comparative studies are required to confirm these findings. Not applicable.