We report an 18-month old male presenting with a right-sided inguinal
hernia and undescended testes. At herniotomy, a uterus and two fallopi
an tubes were found in the pelvic peritoneum adjacent to the two gonad
s which received their blood supply partly along the Mullerian duct re
mnants. The gonads were testes by histological examination. Bilateral
orchiopexy was performed without removal of the Mullerian structures f
or fear of jeopardizing the testicular blood supply. The diagnosis of
persistent Mullerian duct syndrome was confirmed postoperatively by ge
netic and hormonal investigations.