Prolactin and beta-hCG in pregnancy: 24 hour hormone profiles during preterm labour and the last 6 hours up to delivery.

We examined the 24 hour plasma profiles of prolactin and beta-hCG in 7 women with preterm labour between the 30th and 34th week of gestation. The results showed that, despite preterm labour, the circadian rhythm of prolactin was maintained. The beta-hCG levels showed a wide scattering in the normal range which is also characteristic of pregnancy with no complications. In addition we examined the prolactin and beta-hCG levels during the last 6 hours preceding delivery. Here we found significant higher hormone concentrations of hCG in the mothers delivered of female babies than in the mothers of males. This higher hormone level declined continuously during the delivery, however, without significance. We also observed concordant secretion patterns of prolactin and beta-hCG in these cases. Normal hCG and prolactin values were found in mothers delivered of male babies.