The values for the clinical probabilities were:
No form of carrier or prenatal diagnosis available.
Couples with a greater than 10% risk of an affected child:
50% for all diseases considered except CF; and
30% (range: 30 - 70%) for CF.
Couples with a less than 10% risk of an affected child:
80% for all diseases considered.
DNA diagnosis available:
percentage of at risk couple choosing carrier screening, 100% (>10% risk) and 90% (< 10% risk);
percentage of at risk couples choosing (further) offspring, 85% (range: 60 - 100%);
percentage of at risk couples choosing prenatal diagnosis, 90% (range: 60 - 100%); and
termination of pregnancy when the fetus is affected, 99%.
In addition, the percentage of all CF mutations identified after analysis of the 10 most frequent mutations was 85%, the risk of infertility was 10%, and the risk of induced abortion after chorionic villus sampling was 1%.