Urinary excretion of placental male sex-linked protein during pregnancy.

The placental male protein in the maternal urine was examined by means of the column chromatographic method, the same method used in determination of the male protein in human placenta. The urinary examination was made in ten near-term pregnant women, five with male and five with female fetuses. It was found that the male protein was present in the urine of every pregnant woman with a male fetus and was absent in those with a female fetus. The result of this study suggests that the male protein in the placenta is released into the maternal circulation and excreted into the urine during pregnancy. The presence of the male protein in the pregnant women's urine may be used as a criteria in determining the presence of a male fetus.