The impact of prenatal alcohol exposure on frontal cortex development in utero

Objective: Whether prenatal alcohol exposure was associated with a reduction in the frontal cortex was examined. Study Design: Pregnant women (n = 167) received multiple ultrasonographic assessments. During the assessment, brain structures were visualized and measured, including the distance from the posterior margin of the cavum to the calvarium, the distance from the posterior margin of the thalamus to the calvarium, the transcerebellar diameter, and the biparietal diameter. Results: Regression analyses and odds ratios demonstrated that alcohol exposure was associated with a reduction in the frontal cortex, but not other brain structures. Strikingly, the percent of fetuses with a frontal cortex below the 10th percentile increased from 4% for nonexposed fetuses to 23% for heavily exposed fetuses. Conclusion: There was a relationship between frontal brain size and maternal alcohol consumption, suggesting that ultrasonography may be a sensitive tool for detecting alcohol-induced changes in the fetal brain. (Am J Obstet Gynecol 2001;185:737-42.)