Abstract
Chorionic "growth hormone-prolactin" in serum and urine from pregnant women, in serum from umbilical cord, and in amniotic fluid was assayed by a sensitive immunological method dependent on the combination of rabbit antiserum to the growth hormone-prolactin with the iodine-131-labeled hormone. The hormone is detectable in serum and urine early in gestation, and with advancing pregnancy its concentration in serum continues to increase to a maximum during the last trimester. It was not found in serum within 8 hours after delivery.
