Some critical aspects on prenatal diagnosis of sex in leucocyte cultures from pregnant women.

An attempt was made to assess fetal sex by means of chromosome analysis following the procedure of Walkonowska, Conte, and Grumbach (1969). Peripheral venous blood was obtained from 23 pregnant women between 11 and 38 weeks of gestation. Leucocyte cultures were prepared and more than 50 well-defined metaphase plates for each blood sample were examined. Karotype analysis was carried out on the plates with small acrocentrics of G groups. 4 out of 23 women showed 1 or 2 metaphase figures with 46 or 47 chromosomes including 5 acrocentrics. 1 of the 5 small acrocentrics was thought to be the Y chromosome. 3 of the 4 women with 5 acrocentrics containing 4 G-autosomes and a Y gave birth to male infants. It appears that the prenatal diagnosis of sex in maternal blood is theoretically possible but its practical application seems to be unadvisable at the present status of methodology.