Résumé
Herlyn-Werner-Wunderlich syndrome (HWWS) is a very rare congenital anomaly of the urogenital tract involving Mullerian ducts and Wolffian ducts, and is characterized by the triad of uterine didelphys, unilateral obstructed hemivagina and ipsilateral renal agenesis. Generally it is diagnosed at puberty after menarche due to recurrent pelvic pain or abdominal mass. We report 2 cases of female newborns whose fetal ultrasonography (USG) showed unilateral renal agenesis and were diagnosed with HWWS by postnatal evaluation. Both cases were female newborns who were born at term by vaginal delivery. They had no perinatal problems except suspicious findings of unilateral renal agenesis from fetal USG. Abdominal ultrasonography and pelvic MRI were performed after birth, and they were diagnosed with HWWS. The potential complications of this syndrome such as pyosalpinx, pelvic adhesions and increased risk of abortion or infertility can occur, but without complication, the prognosis is very good with simple surgical treatment. If renal agenesis is detected in a fetus or a newborn, possible anomalies of urogenital tract such as HWWS should be considered; and postnatal evaluation should be performed, as a simple surgical treatment before menarche can prevent unnecessary complications of disease.