Am Fam Physician. 2006;73(10):1837
Maternal use of alcohol is considered to be a leading cause of birth defects and developmental delays in the United States. Prenatal alcohol exposure can lead to a range of adverse outcomes, referred to as fetal alcohol spectrum disorders. Diagnostic criteria for the most common condition, fetal alcohol syndrome (FAS), were revised in 2004 by a Centers for Disease Control and Prevention expert group and endorsed by the American College of Obstetricians and Gynecologists and the American Academy of Pediatrics. (The guidelines are available online athttp://www.cdc.gov/ncbddd/fas/documents/fas_guidelines_accessible.pdf.) A review by Floyd and colleagues discusses the implications of the new definitions for practice, stressing the need for the prevention and early detection of FAS.
The most common reasons for under-diagnosis of FAS are a lack of awareness of maternal drinking history and a lack of physician experience with the condition. The facial features of FAS can be subtle in newborns, and the neurologic manifestations may not be apparent at first. Reported prevalence of FAS ranges from 0.5 to 2.0 per 1,000 live births, but rate of diagnosis rises when physicians are familiar with the condition. Diagnosis rests on documented abnormalities in three facial features (i.e., smooth philtrum, thin vermilion border, small palpebral fissures), in growth, and in neurologic function. Specific diagnostic criteria for other fetal alcohol spectrum disorders have not been developed.
Alcohol use, particularly binge drinking, is increasing among women of childbearing age. A 2003 survey found that among women who were not pregnant, 53 percent reported alcohol use and 23 percent reported binge drinking. Among pregnant women, 9.8 percent used alcohol and 4.1 percent reported binge drinking. Alcohol dosage is one of the most important factors in FAS. A correlation has been established between the amount of alcohol consumed and the severity of the adverse effects. The review by Floyd and colleagues stresses the need to detect and intervene in heavy alcohol use in women of childbearing age, especially because one half of pregnancies are unplanned. The fetus in an unplanned or unrecognized pregnancy is at high risk of alcohol exposure, particularly in the early, organ-forming period.
For women who are not pregnant, a limit of one drink per day is recommended. Binge drinking in women is defined as four or more drinks on a single occasion. Any woman consuming more than seven drinks per week or more than three drinks on any day should be assessed for alcohol-related problems. For women who are pregnant, abstinence from alcohol use is recommended. Screening for alcohol use in all adults, and all women who are pregnant, is recommended by the Agency for Healthcare Research and Quality. Two short screening instruments, T-ACE and TWEAK, have been validated for use in women who are pregnant. These instruments take less than one minute to administer and more effectively identify alcohol use than routine physician questioning.
Brief physician intervention that is focused on discussing the risks, assessing the patient's readiness to change, and offering support has been associated with a 20 to 25 percent reduction in alcohol intake and episodes of binge drinking in women. The authors recommend discussion of pregnancy postponement and contraception as well as alcohol reduction in women who are not pregnant to minimize the risk of alcohol exposure in an unplanned pregnancy. Regular follow-up to document changes in alcohol use and to reinforce the use of services to lower alcohol intake is strongly recommended in women at high risk. Brief interventions in women who are pregnant have been associated with significant reductions in alcohol intake and improved infant outcomes.