[Antenatal diagnosis of fetal sex. Method and implications]

An outline of fetal antenatal sex determination and its diagnostic methods are rapidly enumerated. Actual methods are based on direct and indirect identification of sexual chromosomes from three types of cells : desquamated ones in amniotic fluid, fetal lymphocytes circulating in maternal blood and desquamated chorionic cells from endocervical smear. Three methods are utilizable : evidence of sexual chromatine, fluorescence specificity of the Y chromosome and the karyotype. Cells from amniotic fluid permit a correct prediction up to 97,5 p.100. However, the high risk of contamination limits its use. There is a 86 p. 100 diagnostic certainty with fetal lymphocytes in maternal blood or cervical desquamated chorionic cells. Future sex preselection may be contemplated and along with this the speculative social consequences. On the other hand, sex determination and volontary selection are limited at the moment by available technics and also by scientific and medical ethics.