The outcome of 78 pregnancies, monitored by second trimester amniocentesis for prevention of genetic disease, and the outcome of an equal number of matched controls are reported. The controls were selected from the same obstetrical department, among the same population, and were matched for age, number of previous children, abortions and stillbirths. No significant difference was found in Apgar score, birth‐weight and length, duration of pregnancy, placenta condition or malformatio