Neural tube defects in Havana City--incidence and prenatal diagnosis.

An evaluation was made of all cases of neural tube defects born in seven gynaecological hospitals and obstetric centres of Havana, between 1970 and 1980. Neural tube defects were recordable from 492 infants out of 319,228 births. The families concerned were briefed in human genetics and informed about the possibility of prenatal diagnosis of anencephaly and bifid spine (spina bifida aperta). Some of them had a record of this defect. Amniocentesis was applied to 30 women with an empirical risk of 1:20, and alphafoetoprotein was analysed in their amniotic fluid. Anencephaly was diagnosed in one case and confirmed by termination of pregnancy. The occurrence of neural tube defects usually is of spontaneous nature, and incidence is relatively high. Therefore efforts are now being made to introduce a scheme of prenatal screening based on alphafoetoprotein assessment in the serum of pregnant women.