A 21-Year Longitudinal Analysis of the Effects of Prenatal Alcohol Exposure on Young Adult Drinking

Abstract

Because drinking at age 14 reportedly is a risk factor for a range of disorders related to alcohol use, this study was undertaken to learn whether prenatal alcohol exposure predisposes to alcohol problems in the young adult years. Maternal drinking during pregnancy was ascertained by interviews of women receiving prenatal care at midpregnancy. Parental substance use and the family environment were periodically evaluated from the prenatal period to age 21 to 23 years, at which time the offspring reported their drinking history and completed the Alcohol Dependence Scale (ADS). A total of 433 families were interviewed 22 years after the initial prenatal assessment. All but 20% of women drank alcohol while pregnant and in the months before they learned they were pregnant. Heavy episodic drinking (5 or more drinks at about the same time) was self-reported by 31% of women. Two infants were diagnosed at birth as having fetal alcohol syndrome. Approximately 83% of the offspring acknowledged being current drinkers, with an average of nearly 6 drinking episodes per month and an average of nearly 4 drinks on each occasion. The rate of heavy episodic drinking was 36.5%. The ADS indicated at least mild alcohol dependence in 35 offspring, 8% of the total. A variety of statistical methods, including regression analysis, indicated that prenatal alcohol exposure was significantly associated with alcohol problems at age 21. This relationship was independent of a family history of alcohol problems, nicotine exposure, other prenatal exposures, and postnatal environmental factors such as parental use of other substances. Although most persons who drink heavily at age 21 do not later develop alcohol misuse disorders, those with persistent problems in midlife do typically start drinking in adolescence or early adulthood. How those at risk for alcohol-related problems later in life could be identified remains to be discovered.