Fertility in men exposed prenatally to diethylstilbestrol

Prenatal exposure to diethylstilbestrol does not appear to affect a man's fertility. Researchers contacted 494 men between the ages of 38 and 41 whose mothers had taken part in a randomized trial of diethylstilbestrol to treat pregnancy complications between 1950 and 1952. A total of 253 men had been exposed to the drug prenatally during the study and 241 had not been exposed. Fifteen percent of those exposed to the drug had a testicular malformation, compared to 5% of those who were not exposed. However, the incidence of infertility was no higher in those exposed than in those not exposed. Men with testicular malformations were no more likely to be infertile than those without such malformations. The rates of pregnancy in the men's female partners were also similar in the two groups.