Single measurements of chorionic gonadotropin and schwangerschafts protein for assessing gestational age and predicting the day of delivery.
Human chorionic gonadotropin (hCG) and schwangerschafts protein 1 (SP1) were measured in blood samples from 26 women at 36-60 days of normal pregnancy. There was a highly significant linear correlation between the levels of these placental proteins and the stage of gestation as judged from the day of the last menstrual period and the day of spontaneous delivery at term. There was no relationship between hCG and SP1 levels in early pregnancy and the sex or birth weight of the child. These findings confirm the previous demonstration of the practical value of biochemical estimations in dating an early pregnancy. In addition, and for the first time, they demonstrate that such determinations may be used to ascertain the expected date of term delivery.