FRIDAY, March 25 (HealthDay News) -- Teens whose mothers drank alcohol regularly throughout the first trimester of pregnancy have a threefold increased risk of developing severe behavior problems, a new study warns.

Researchers from the University of Pittsburgh School of Medicine and Medical Center analyzed data collected from 592 children and their mothers. The mothers were evaluated when four and seven months pregnant and shortly after childbirth and then, along with their children, when the children were 8 months old, 18 months old and 3, 6, 10, 14 and 16 years old.

The quantity, frequency and patterns of alcohol use -- including beer, wine and liquor -- by the women during pregnancy were summarized as average daily alcohol consumption.

When the children were 16 years old, those whose mothers had consumed, on average, one or more alcoholic drinks a day in the first trimester of pregnancy were three times more likely to meet the criteria for conduct disorder than were teens whose mothers had consumed less than one drink a day or no alcohol at all, the investigators found.

Conduct disorder refers to a pattern of serious behavior problems that last for more than a year and includes, according to the researchers, such things as property destruction, aggression toward people and animals, dishonesty or theft, and serious rule violations.

The study is published in the March issue of the Journal of the American Academy of Child and Adolescent Psychiatry.

"From a clinical perspective, prenatal alcohol exposure should be considered as another risk for conduct disorder. The next steps in research should be to define the interactions between prenatal exposures, environmental factors and heritability. This would allow a more complete picture of the relations between prenatal alcohol exposure and conduct disorder," concluded Cynthia A. Larkby, of the University of Pittsburgh, and colleagues.

More information

The March of Dimes has more about the dangers of drinking alcohol during pregnancy.