Pregnant women consumed just as much alcohol in 2005 as they did in 1991, with 12% drinking at least once during pregnancy and 2% reporting binge drinking.
The findings illustrate the small effect of national educational programs that have been aimed at decreasing this dangerous behavior, according to the primary author, Clark Denny, Ph.D.
In Healthy People 2010, the national health agenda that was published in 2000, Dr. David Satcher, the U.S. Surgeon General at that time, set abstinence targets of 95% for alcohol and 100% for binge drinking among pregnant women.
“The prevalence of both types of drinking behavior among pregnant women remains higher than the Healthy People 2010 targets and greater progress will be needed to reach them,” Dr. Denny wrote (MMWR 2009;58:529-32).
The 15-year study found that women aged 35 to 44 years had the highest incidence of drinking during pregnancy (18%), wrote Dr. Denny, an epidemiologist from the Centers for Disease Control and Prevention. Rates were also higher in college-educated women, employed women, and unmarried women.
The study was based on data collected from 1991 to 2005 through the Behavioral Risk Factor Surveillance System surveys. These annual surveys randomly poll community-dwelling U.S. adults about behavioral health issues. The CDC study included data collected from women aged 18 to 44 years, who were asked about alcohol use (at least one drink in the last 30 days) and binge drinking (at least five drinks on any one occasion in the last 30 days).
During the 15-year period, 533,500 women were surveyed; 22,000 (4%) reported being pregnant at the time of the survey. The average annual percentage of any alcohol use among the pregnant women was 12% and did not change from 1991 to 2005. The average annual percentage of pregnant women who said they binged was 2%; again, that percentage was stable over the survey period.
From 2001 to 2005, the study also examined the relationship between drinking during pregnancy and demographic factors. Age was associated with both any drinking and binge drinking. The oldest women (35 to 44 years) had the highest drinking rate (18%), while the youngest women (18 to 24 years) had the lowest rate (9%). Age was not highly associated with binge drinking.
Education, employment, and marital status were also associated with drinking during pregnancy. Any drinking was higher in employed women than unemployed (14% vs. 8%), and in unmarried women than married women (13% vs. 10%). Binge drinking was also more common in employed than unemployed women (2% vs. 1%), and unmarried women than married women (4% vs. 1%).
The reasons for these associations are unclear, Dr. Denny wrote. “Some possible reasons include that older women might be more likely to be alcohol dependent and have more difficult abstaining while pregnant; more educated and employed women might have more discretionary money for the purchase of alcohol; and unmarried women might attend more social occasions where alcohol is served.”
The rates of drinking and binge drinking were higher among nonpregnant women (54% and 12%, respectively). Prepregnancy alcohol use is a strong predictor of use during pregnancy, and many women who drink continue to do so before realizing that they are pregnant, Dr. Denny noted. “Approximately 40% of women realize they are pregnant at 4 weeks of gestation, a critical period for fetal organ development.”
The findings confirm the need for alcohol use screening and counseling among all women, he wrote in a press statement. “By screening and advising women about the risks of drinking while pregnant, health care providers can play a key role in reducing rates of fetal alcohol syndrome. This study revealed that there is still a great need for health care professionals to routinely ask all women who are pregnant or at risk of being pregnant about their alcohol consumption.”