New mom-child alcohol link found

A woman's heavy drinking during pregnancy triples the chances that her child will show signs of alcohol problems by young adulthood, new research suggests.

Maternal alcohol use has been linked to a variety of problems in offspring, including mental retardation, developmental delays and behavioral disorders. But this study is the first to tie prenatal alcohol exposure to later drinking problems, said co-author Ann Streissguth, head of the University of Washington's Fetal Alcohol and Drug Unit.

The finding, published in the Archives of General Psychiatry, is part of a broader UW study that has been tracking 433 young adults since before birth.

The study began in 1974 when it was common and socially acceptable for pregnant women to drink alcohol. Eighty percent of mothers in the study drank during pregnancy or during the months before they knew they were pregnant.

Nearly one-third of the mothers drank "heavily" — five or more drinks — on at least one occasion during pregnancy. When their children were interviewed at age 21, 14 percent showed signs of alcohol problems, compared with just 4.5 percent of those whose mothers drank less.

The link held true even after researchers controlled for factors such as demographics, family history of alcoholism, growing up around alcohol and exposure to nicotine.

"This raises the possibility that the inheritance of alcoholism is more complex than just genetics," said Dr. Sam Cullison, director of Swedish Medical Center's addiction-recovery program. "It could partly be a poisonous effect of prenatal exposure."

The study found no difference in the reported amount of drinking by 21-year-olds whose mothers drank heavily in pregnancy versus those whose mothers hadn't drunk heavily. (Overall, more than 80 percent of the children said they were current alcohol users, consuming an average of 3.79 drinks per occasion, 5.77 times per month.)

The disparity lay in how the two groups handled alcohol. Those born to heavy-drinking mothers were three times more likely to show symptoms of alcohol dependence, including blackouts, hangovers, being physically sick, staggering and unclear thinking.

The fact that the offspring were 21 when they were interviewed complicates the findings because the college-age years are generally the period of heaviest drinking for most people. Many people who drink heavily during those years curb the habit by their mid-20s; however, most lifelong alcoholics begin showing drinking problems by this age, so it's hard to identify who's who, said lead author Dr. John Baer, a research associate professor of psychology at the UW.

"We don't know if this effect is seen at one point in time or if this leads to long-term problems with alcohol," Baer said, adding that the researchers will continue to follow the group.

A previous study of this population at age 14 showed the first hints of a link between prenatal exposure and experimenting with alcohol.

The findings underscore the message that women who have a chance of becoming pregnant should be vigilant about avoiding alcohol, said Streissguth, who more than 20 years ago first helped identify fetal alcohol syndrome. FAS refers to a set of physical, mental and behavioral defects caused by a woman's use of alcohol during pregnancy.

The Centers for Disease Control and Prevention estimates between 1,200 and 8,800 babies are born in the United States each year with FAS and many more have less-severe impairments.

Julia Sommerfeld: 206-464-2708 or jsommerfeld@seattletimes.com