A clinical service for prenatal diagnosis.

A centralised clinical prenatal diagnostic service has been established and the results of amniocentesis in 174 patients are discussed. Termination of pregnancy was performed in 3 patients on the basis of cytogenetic abnormalities (47,XXY, 47,XXX, 47,XY 21+): in 2 patients with anencephalic fetuses on the basis of alpha-fetoprotein and ultrasound investigations, and 1 patient with fetal Hurler's syndrome. One mother, aged 45, refused amniocentesis and gave birth to a child with Down syndrome. Amniocentesis was followed by fetal death and abortion in 3 patients, all of whom had repeat amniocentesis. Cytogenetic results were not obtained from cell-culture in 9 out of 155 patients, but it was possible to explain all but 2 of the failures. An unexplained error in fetal sex determination occurred once.