Congenital imperforate hymen in a newborn presenting with vaginal protrusion and abdominal distension: a rare case report.

Imperforate hymen is a rare neonatal anomaly that can cause hydrocolpos and urinary obstruction. We report a newborn girl who presented on day three with abdominal distension and was found to have severe hydrocolpos from an imperforate hymen, leading to bilateral hydronephrosis but with preserved renal function. A hymenal incision effectively drained the accumulated secretions, resulting in rapid clinical improvement and complete resolution on follow-up imaging. Hydrocolpos occurs due to fluid accumulation behind a vaginal obstruction such as an imperforate hymen, and early recognition is essential to prevent complications like hydronephrosis and renal impairment. In this case, timely imaging and focused examination enabled prompt hymenotomy and immediate decompression. This highlights the importance of clinical suspicion, early imaging, and careful genital examination in female neonates. Neonatal imperforate hymen can cause significant hydrometrocolpos and hydronephrosis, emphasizing the need for early recognition and intervention.