Ethyl linoleate in meconium: A biomarker for prenatal ethanol exposure

Background: Fetal alcohol syndrome, fetal alcohol effects, alcohol-related neurodevelopmental disorder, and alcohol-related birth defects, all terms r eferring to the spectrum of consequences of in utero exposure to ethanol, a re a major public health burden. There is currently no laboratory test to i dentify newborns exposed to ethanol in utero. Meconium was analyzed for eth yl linoleate, a metabolite of ethanol, as a biological marker for fetal eth anol exposure. Methods: Samples of meconium were obtained from 248 infants and analyzed for fatty acid ethyl esters. Detailed maternal alcohol, tobacc o, and drug use histories were obtained within 1 month of giving birth. Res ults: The detection of ethyl linoleate in meconium was called a positive te st. The mean number of drinks reported per week in the month before pregnan cy, the first trimester, and overall were significantly higher in the posit ive group (unadjusted: 9.2 +/- 1.9 vs. 4.3 +/- 1.4, p = 0.004; 7.3 +/- 1.7 vs. 3.8 +/- 1.2, p = 0.03; and 6.1 +/- 1.3 vs. 3.0 +/- 1.0, p = 0.006). A p ositive test was not associated with marijuana, cocaine, or tobacco use. Se nsitivity and specificity of the test were 72% and 51% to distinguish women who reported 1 or more drinks/week in the third trimester from women who d enied use, and 68% and 48% to distinguish women who used greater than or eq ual to 1 drink/week from women who used <1 drink/week in the month before p regnancy. Conclusions: The presence of ethyl linoleate in meconium is the f irst reported biological marker for maternal ethanol use during pregnancy. Because of the inherent inaccuracy associated with the use of self-reportin g, the establishment of true values of sensitivity and specificity will req uire validation where the presence, quantity, and timing of exposure to alc ohol is known. Further validation of this marker will permit identification and intervention of at-risk infants.