Prevalence of dysmorphic uterus in infertile women by 3D-TVUS: a retrospective longitudinal cohort study.

BACKGROUND: The true prevalence and clinical significance of congenital uterine malformations (CUM), particularly the dysmorphic uterus, in infertile populations remain a matter of debate, largely due to historical limitations in diagnostic methods. This study aimed to (1) determine the prevalence of CUM in an infertile cohort using modern, objective three-dimensional transvaginal ultrasound (3D-TVUS) criteria; (2) evaluate reproductive outcomes following surgical correction; and (3) investigate associated intrauterine pathologies that may contribute to infertility. METHODS: This a retrospective longitudinal cohort study included 154 women presenting for infertility investigation at a university hospital tertiary referral center between January 2020 and December 2022. All patients underwent 3D-TVUS for uterine assessment based on Congenital Uterine Malformation by Experts (CUME) criteria. Women diagnosed with CMU underwent hysteroscopic metroplasty. The primary outcomes were the prevalence of CMU subtypes and the 1-year cumulative live birth rate (LBR). Statistical analysis was performed using one-way ANOVA and chi-square tests. RESULTS: CMU was identified in 47/154 (30.5%) women. Dysmorphic uterus was the most common anomaly, present in 42/154 women (27.3% of the total cohort; 89.4% of all anomalies). A significant association was found between dysmorphic/septate uteri and the presence of endometrial polyps (45.2%/40.0% vs. 8.5% in normal uteri; P < 0.001). After metroplasty, the 1-year cumulative LBR for the dysmorphic uterus group (26.2%) was comparable to the normal uterus group (20.6%; P = 0.907). The miscarriage rate per clinical pregnancy was also similar between the dysmorphic (15.4%) and normal uterus (25.7%) groups. CONCLUSIONS: Using modern, objective 3D-TVUS criteria, the prevalence of a dysmorphic uterus in infertile women is substantially higher than previously reported. Surgical correction may improve reproductive outcomes to levels comparable to those in infertile women with normal uterine anatomy. Furthermore, the novel association with endometrial polyps warrants further investigation and underscores the importance of a comprehensive uterine assessment during the infertility workup.