The effects of maternal alcohol consumption and cigarette smoking during pregnancy on acoustic cry analysis.

During the last trimester of pregnancy, 127 primiparous Irish mothers were interviewed to ascertain their history of alcohol and tobacco use. Confounding effects due to other drugs were not a factor in this sample. Mothers consumed an average of .21 ounces absolute alcohol (AA) per day, with 62% classified as moderate drinkers, 10.6% as heavy drinkers, and 26% as nondrinkers. Neurobehavioral status was measured using acoustic characteristics of the infant's cry, collected on the third day of life. Multiple regression analysis showed that more ounces AA per day was related to more dysphonation and higher first formant, while more cigarette smoking was related to higher pitch, higher second formant, and more variability in the second formant. Analysis of variance comparisons of these 3 alcohol groups demonstrated significant cry effects on infants of heavy drinking mothers.