Evaluation of postterm pregnancies with maternal serum placental lactogen and alpha-fetoprotein concentrations.
Studies of maternal serum placental lactogen (hPL) levels in 70 women delivering beyond 42 weeks of gestation revealed significantly lower levels of hPL when the offspring had one or more of ten signs of postmaturity or distress. A sequential combination of hPL measurements and intrapartum fetal heart rate monitoring (FHRM) (performed in 61 patients) gave a high degree of prognosis (75% of abnormalities detected, 88% with normal tests having no abnormalities). Considered separately, neither maternal serum hPL levels nor FHRM predicted abnormalities in the offspring to the same high degree. On the other hand, hPL could not be correlated with staining, desquamation, and the presence of meconium in the amniotic fluid at delivery, these criteria being considered separately or in combination. Maternal serum alpha-fetoprotein (AFP) levels during late gestation showed considerable variation and did not permit distinction between pregnancies with or without an abnormality in the offspring.