Based on neonatal examination at birth, it has been estimated that epi
leptic women have a 2-3 times greater risk of giving birth to an infan
t with congenital anomalies. But anticonvulsant drugs may also have mo
re subtle influences on the developing foetus which are not visible at
birth but only emerge later in life. Evidence for these functional te
ratogenic influences has been provided by animal research and follow-u
p studies in young children. This article discusses these findings in
human and animal studies. In addition, the outline of a study carried
out at the Department of Obstetrics and Neonatology, Academic Medical
Centre, Amsterdam, is described. In this study cognitive functioning,
fertility and gender role behaviour of young adults, who had been pren
atally exposed to barbiturates and/or hydantoins was examined.