RESUMEN
Herlyn-Werner-Wunderlich syndrome is characterized by a triad of uterine didelphys, obstructed hemivagina, and ipsilateral renal agenesis. The syndrome should be suspected in any young woman with abdominal pain or cyclic dysmenorrhea, and radiologic evidence of müllerian duct and renal anomalies. Herein is presented the case of a 25-year-old woman with a rare variant of Herlyn-Werner-Wunderlich syndrome, characterized by an anomalous connection between the 2 endocervical canals, who underwent hemivaginal septum resection to relieve progressively worsening dysmenorrhea. The right hemivaginal septum was resected medially from the left cervix and laterally off the right vaginal wall. Hydrodissection between the hemivaginal septum and right cervix facilitated surgical resection. After resection of the hemivaginal septum there was complete resolution of dysmenorrhea and no recurrence of hematometra or hematocolpos.