Abstract
Vaginal atresia was observed with 5.8% morbidity (58/998 females) in adult BALB/cA-nu/+ and -nu/nu mice. Twenty-seven of the diseased mice were pathologically examined. In the affected mice, the vaginal orifice failed to open even 2 months of age and the perineal region was swollen, being scrotumlike. In addition, an increase of the follicle and a decrease of the corpus luteum were noticed in the ovary. This disorder was regarded as a malformation concerned with a heredity.