Abstract

Between 1940 and 1970, up to 10000 women in England and Wales, and up to 2 million in the USA, received prophylactic diethylstilboestrol (DES) in an attempt to improve the outcome of pregnancy. Trials performed only later showed that DES did not reduce the incidence of abortion, toxaemia, prematurity or perinatal mortality.¹ However, the use of DES in pregnancy is now known to damage the fetal reproductive tract: it can cause malignancy, maldevelopment of the urogenital tract, infertility, increased perinatal mortality and psychological problems. The complex issues raised by this disaster are not just historical, but still affect people now and have important lessons for the future.²