This study assessed testicular viability after 476 inguinal procedures performed in 338 infants under 6 months of age, between 1974 and 1993. One hundred twenty-one elective hernia repairs (contralateral explorations) were compared with 355 hernia repairs complicated by incarceration and/or orchiopexy. Clinical examination of 323 testes in the early postoperative period showed 20 atrophic testes. Since January 1994, 71 of the 338 patients have had testicular measurements obtained through ultrasonography (US). An additional 13 atrophic testes were found during US examination. Of these, nine were believed to be normal during early postoperative examination. Assuming that US examination will confirm atrophy in the 20 atrophic testes noted early in the postoperative clinical evaluation, and that all other testes not yet scanned are found to be normal, the minimal atrophy rate (MAR) would be 9.3% (33 of 355). Neither operative nor early postoperative testicular assessment correlates with ultimate testicular survival. Testicular pathology may become more evident after puberty, and the real incidence of atrophy may increase.