[Prenatal diagnosis of sex by determination of amniotic testosterone and FSH].

Among hormones which can be determined in the amniotic fluid in the mid-pregnancy period, testosterone and F.S.H. allow the best discrimination between sexes (Figure 1). Moreover, F.S.H. is clearly increasing during the 2d trimester of pregnancy in case of a female fetus. This is a quick and reliable method which uses a small quantity of amniotic fluid. Combined with chromosomal analysis, it increases the accuracy of the sex diagnosis and indicates a repeat amniocentesis if there is a discrepancy between karyotype and hormonal determinations.