Prenatal sex detection with endocervical smears: successful results utilizing Y-bodyfluoroscence.

Highly equivocal results, regarding procedures for the prenatal detection of fetal sexls found in the endocervix, are reported in the literature dating from 1971. The far-reaching genetic and obstetric implications of such procedures led us to investigate endocervical smears from 36 patients (taken during all three trimesters) and study the validity and practicality of this test. Fetal sex was correctly predicted in 31 of 36cases and all 18 male predictions delivered males. In addition, many previously reported and newly found sources of error were encountered and evaluated. It is concludedthat there are indeed cells of fetal origin being shed into the endocervix and they canbe used as a reliable indicator of fetal sex in all three trimesters.