Prediction of fetal sex from cytologic examination of amnionic fluid

Maternal serum human chorionic gonadotropin concentrations and fetal sex prediction

The feasibility of using maternal serum human chorionic gonadotropin (hCG) concentrations for prenatal sex prediction was examined. hCG was mesured in 822 serum samples from 560 women with uncomplicated pregnancies. Significantly higher hCG concentrations were found in the serum of women bearing female fetuses than in the serum of women bearing male fetuses during the third trimester, especially during the 10th lunar month. The data were utilized to construct probability graphs for fetal sex prediction based upon a single maternal serum hCG determination during the third trimester and during the 10th lunar month. However, the utility of these graphs is limited by the small proportion of pregnant women with serum hCG concentrations that were high or low enough to allow a prediction with high probability.

Nuclear chromatin determination in amniotic fluid cells for prenatal sex prediction in the macaque

Amniotic fluid cells obtained after the ninetieth day of gestation in the macaque were analyzed for nuclear chromatin. The technique proved reliable for the prediction of fetal sex.

Amniotic fluid cells; prenatal sex prediction and culture

Sex chromatin studies were carried out on small amounts of amniotic fluid obtained by amniocentesis or from intact amniotic sacs removed at hysterotomy. Provided that satisfactory preparations were obtained the accuracy of fetal sexing was 87%. Nevertheless, in the management of a pregnancy in which there is a risk of a serious X-linked recessive disorder, repeat amniocentesis may be necessary to ensure satisfactory specimens.Of 90 samples of fluid cultured, satisfactory growth was obtained in 49; the success rate was not increased by the addition of stimulants to the culture medium. It is suggested that between the 13th and the 16th week of pregnancy is the optimum time for amniocentesis to obtain cells for culture, since sufficient cells are then present in a small volume of fluid and therapeutic abortion would still be possible once the results were available.