[Effects of prenatal exposure to phthalate ester on both testicular descent and urogenital development in rats].

Mono-n-butyl phthalate (MBP) was administered to pregnant rats to investigate the effect of phthalate ester on both testicular descent and urogenital development in prenatal rats. Ten pregnant rats were separated into two groups. In-group 1; rats were fed with special rat chow containing 1% of MBP from the 14th to the 19th gestational days. In group 2; rats fed with normal rat chow were used as control. At birth, reduced anogenital distance was seen in MBP-treated male offspring, and additional adverse effects on androgen-dependent organs were seen at the age of 70-80 days. Undescended testis, hypospadias, short prepuce, prostatic hypoplasia and hypolastic seminal vesicles were seen in mature male offspring. The results suggest that prenatal administration of MBP may act as an antiandrogenic chemical and thereby inhibit testicular descent and urogenital development in rats.