Serious psychiatric outcome of subjects prenatally exposed to diethylstilboestrol in the E3N cohort study.

BACKGROUND Prenatal exposure to diethylstilboestrol (DES) may induce neurodevelopmental disturbances potentially mediating an increased risk of psychiatric disorders in exposed subjects. Most findings of an increased prevalence of psychiatric disorders in men and women prenatally exposed to DES are not easy to interpret because of selection biases. METHOD Information on hormonal treatment during pregnancy and on offspring's medical outcome was collected from women participating in the Etude Epidemiologique de femmes de la Mutuelle Générale de l'Education Nationale (E3N) prospective cohort who completed consecutive postal questionnaires on a range of medical events since 1990. Information on hormonal treatment during pregnancy was collected in 1992 and on offspring's medical outcome in 2004. The psychiatric outcome of subjects prenatally exposed to DES was compared to that of their unexposed siblings. RESULTS A total of 1352 mothers with DES treatment for at least one pregnancy provided information on 1680 exposed children and 1447 unexposed siblings. After adjustment for duration of follow-up, educational level, history of obstetric complication, prenatal exposure to progestagen drugs or other hormones and parental history of psychiatric hospitalization, no association was found between prenatal exposure to DES and occurrence of strictly defined serious psychiatric outcome (suicide or psychiatric hospitalization) [adjusted odds ratio (OR) 0.8, 95% confidence interval (CI) 0.5-1.2], or of broadly defined serious psychiatric outcome (same events plus psychiatric or psychological consultation) (adjusted OR 1.0, 95% CI 0.8-1.2). CONCLUSIONS These findings suggest that the impact of prenatal DES exposure on foetal brain development, if any, is unlikely to increase the risk of serious psychiatric disorders.