Association between unaccountably high maternal alpha feto-protein and increased fetal risk

An unaccountably high maternal serum alpha-fetoprotein level at 16-18 weeks of pregnancy is associated with increased risk to the fetus in a continuing pregnancy. Thirty-one pregnancies with confirmed high levels at 16-18 weeks produced 10 preterm live and 8 liveborn small-for-date babies and 3 early neonatal deaths. Although the incidence of neural tube defects is decreasing, routine assay of maternal serum AFP at 16- 18 weeks should be continued to give possible warning of extra risk to the fetus.