Prenatal screening for cystic fibrosis: 5 years' experience reviewed

Background Although several programmes of prenatal screening for cystic fibrosis have been completed and reported, there are still uncertainties about rates of take up and also about the action of parents identified as having a one-in-four risk of an affected child. I report 5 years' experience with the two-step and couple models of prenatal screening of cystic fibrosis. Methods Screening has been available at two antenatal clinics in Edinburgh, UK, since January, 1992, first on a research basis and then routinely. 25 000 couples have been screened. Findings Take-up rates for the two-step and couple models of delivery are very similar at about 70%. Take-up rates did not change when screening moved from a research to a routine service. Of 22 high-risk couples identified entirely through screening, 20 (91%) opted for prenatal diagnosis. Four couples returned for second and two for third monitored pregnancies. In all eight cases where affected fetuses were identified, pregnancy was terminated. Interpretation These data remove one of the few remaining obstacles to a general implementation of prenatal screening for cystic fibrosis.