Clinical characteristics and outcomes of anterior anus in female infants: a multicenter retrospective cohort study.

Background: Anterior anus (AA) is a congenital anatomical variant with unclear clinical implications and management strategies. This study evaluated the clinical features, associated anomalies, and outcomes of AA in female infants.

Methods: This multicenter retrospective cohort study included infants diagnosed with AA between 2020 and 2024 at six tertiary referral centers in South Korea. The clinical characteristics, coexisting anomalies, and outcomes including constipation and urinary tract infections were analyzed.

Results: Among the 64 patients included in this study, 51.6% had a concomitant perineal groove. Congenital heart diseases were the most common coexisting anomaly, occurring in 32 patients. During a mean follow-up of 22.9 months, constipation was observed in 23% of the patients. Urinary tract infections were not observed. The perineal groove resolved spontaneously in 87.9% of cases.

Conclusion: AA is a benign anatomical variant that does not increase the risk of constipation or urinary tract infections. Given the observed association with congenital heart disease, cardiac evaluation should be considered when clinically indicated.