[Screening for Down's syndrome in the 2d trimester of pregnancy: initial results].

A total of 332 pregnant women with risk of foetal aneuploidy underwent amniocentesis between January 1991 and August 1992: 247 women (74 per cent) for advanced age over 35 years and 85 younger ones (26 per cent) because of significant risk of Down's syndrome as a result of multimarker screening. Maternal serum alpha-fetoprotein, intact human choriogonadotropin and age were used as variables for combined individual risk evaluation according to Wald et al. The Demo version of ALPHA computer programme was used for risk computations. Two prenatally detected cases of Down's syndrome from a total of 5 were from pregnancies of younger mothers aged 18 and 23 years. Various screening protocols and strategies combining age and biochemical variables are discussed.