SERUM SCREENING FOR DOWNS-SYNDROME IN WOM EN AGED UNDER 35 YEARS WITHAN AGE-UNRELATED INDEX

The need for alternatives to amniocentesis, beset by 1% abortion rate, has been increasingly voiced over the past years and also includes th e under 35 age group. However, the known age-dependent screening progr ams such as Alpha program according to Wald (1988) and the Dermalog Pr ogram according to Norgaard-Pederson (1990) only yield a detection rat e of 50 or, at best, 70% (Muller, 1992) for this age group. We tried t o improve this result by index calculation. Compared to the tested age -dependent screening programs the Ulm Index achieves a 25 to 40% highe r detection rate (85%). For pregnant women beyond 35 years the detecti on rate of Down's syndrome can even be raised to 95-100% by a combinat ion of the Alpha or Dermalog program with the Ulm Index, without entai lling an increase in the rate of false-positive results.