Effects of alcohol, cigarettes, methamphetamine and marijuana exposure during pregnancy on maternal serum alpha-fetoprotein levels at 20-24 weeks’gestation

Addressing the burden of stillbirths is a worldwide priority.1 As many stillbirths are not associated with known risk factors, including previous obstetric history in primigravidas,2 the value of routine blood tests such as maternal serum alpha-fetoprotein (MSAFP) to identify pregnant women at risk should be explored. Although the main indication for MSAFP analyses in the mid-trimester is the exclusion of fetal neural tube defects,3 unexplained raised values are associated with stillbirths,4 low birth weight and fetal growth restriction5–8 and preterm delivery.9,10 In addition, elevated MSAFP levels.9,11,12 have also been associated with placental abruption, one of the main causes of stillbirth in high13 and low-income countries14 or in mixed populations.15 Alcohol use during pregnancy may be associated with placental abruption,16–18 stillbirth,15 and small-for-gestational-age newborns.19 Cigarette smoking during pregnancy has also been associated with placental abruption,20 stillbirth21 and fetal growth restriction.22 It is therefore essential to know how environmental conditions such as smoking, drinking and the use of marijuana and methamphetamine affect MSAFP levels, both in pregnancies with normal and adverse outcomes, to improve interpretation of unexplained raised MSAFPvalues. The Safe Passage Study (SPS) of the Prenatal Alcohol in SIDS and Stillbirth (PASS) Network was undertaken to test the hypothesis that prenatal alcohol exposure is associated with increased risk for stillbirth and/or sudden infant death syndrome (SIDS).23 Detailed evaluations, including MSAFP, were performed during pregnancy to assess fetal growth and placental function. Information from the SPS would therefore provide valuable information on the interpretation and significance of MSAFP values.