[Prenatal sex determination from the maternal saliva (author's transl)].

A modified Zimmermann reaction (detection of 17-keto-steroids) has been tested for its applicability to fetal sex diagnosis after 20 weeks of pregnancy. In 90 pregnant women the overall reliability of prediction was only 52%. It increased, however, to 67% by analyzing non-morning samples of saliva, while it decreased to 40% if the first saliva was collected. The sensitivity of the method was found to be unequivocally too low to measure salivary androgens. While this procedure in its present form is not suited to antenatal sex determination, further studies of the still unknown nature of the colour reaction might lead to a new understanding of the changes in salivary composition during pregnancy.