Results of 12 years' combined maternal serum alpha-fetoprotein screening and ultrasound fetal monitoring for prenatal detection of fetal malformations in Havana City, Cuba.

Progressively since 1982 and as part of a nationwide programme for the diagnosis and prevention of genetic diseases, maternal serum alpha-fetoprotein (MS-AFP) screening and ultrasound fetal monitoring has been implemented in all pregnant women in Cuba. In Havana City, 328,983 pregnant women underwent MS-AFP screening between 15 and 19 weeks of gestational age. With a cut-off level of > or = 2 multiples of the normal median (MOM), 1767 amniocenteses were carried out to determine the levels of amniotic fluid AFP and 685 malformed fetuses were diagnosed. By ultrasound fetal monitoring, an additional 686 malformed fetuses were detected. As a result of the programme, the birth prevalence of neural tube defects has fallen by 90 per cent.