Placental Morphology in Fetal Alcohol Spectrum Disorders

Aims: Maternal alcohol drinking adversely affects pregnancy outcome. Although fetal health and development are highly dependent upon the integrity of placentation, little is known about placental morphology following gestational exposure to alcohol in humans. Methods: In this clinical study, subjects were recruited between 2010 and 2013 from an outpatient substance abuse and mental health treatment center for women. Data collected included maternal age, substance abuse history, comorbidities, pregnancy outcomes, gestational age at delivery, birth weight and placental weight. Placental histopathological lesions associated with uteroplacental malperfusion (UPM) were scored under code. Villous cytotrophoblasts reflecting another measure of UPM were immunostained with E-cadherin and quantified using stereology. Inter-group comparisons were made using univariate or multivariate analysis. Results: Of the 92 women enrolled in the study, 61 (66%) had histories of alcohol use during the pregnancy while the remaining 31 served as controls. The alcohol-exposed group significantly differed from controls based on (a) higher rates of smoking and polydrug use during pregnancy, (b) lower mean gestational age and birth weight of their infants, (c) elevated UPM scores, (d) increased densities of villous cytotrophoblastic cells and (e) more extensive chorangiosis in placenta. Logistic regression analysis demonstrated alcohol to be the only significant predictor of these outcomes and responses. Conclusions: Gestational alcohol exposure is significantly associated with UPM, which could account for the higher rates of preterm delivery and reduced mean birth weights. Since chorangiosis reflects altered placental oxygen dynamics, the greater abundance of this abnormality could represent a compensatory response to UPM. Short Summary: In this clinical study, we assessed the effects of maternal alcohol drinking on placental morphology. Applying a cumulative scoring system, we determined that gestational alcohol exposure is significantly associated with uteroplacental malperfusion, which could account for the higher rates of preterm delivery and reduced mean birth weights.