FRIDAY, Feb. 15, 2002 (HealthDayNews) -- Danish researchers who have already found a connection between alcohol use and a higher risk of miscarriage now say that drinking during pregnancy also increases the risk of stillbirth.
The researchers, from Aarhus University, found women who consumed five or more drinks per week were nearly three times more likely to deliver a stillborn baby than were women who had less than one drink a week.
In the first study, announced last week in the February issue of the journal Alcohol and Alcoholism, the team found that five or more drinks of alcohol consumed during the first trimester increased the risk of miscarriage. Surprisingly, the study also found that alcohol had no such effect during the second trimester.
However, in those women who did not lose their babies during the first trimester and continued to drink, up to as many as nine of every 1,000 went on to deliver stillborn babies.
The latest research appears in today's issue of the American Journal of Epidemiology.
"The message here is as clear as any can be: alcohol and pregnancy don't mix. And to drink while you are pregnant is to not only put your pregnancy at risk, but to put your baby at risk for a number of serious potential outcomes," says Dr. Andrei Rebarber, assistant professor of obstetrics and gynecology at New York University Medical Center. Rebarber did not participate in the study.
The researchers say they aren't clear how alcohol caused the stillbirths. However, they hint at the possibility that it could be related to dysfunction of the placenta, the sac that surrounds the baby in the uterus.
For Rebarber, the theory makes sense, and may even be what links alcohol to miscarriage.
"If, for example, the alcohol is causing some type of problem within the placenta, it could mean that it in some way also interferes with the implantation, which could account for the increased risk of miscarriage," he says.
Often, placenta-related pregnancy problems occur, says Rebarber, because of a decrease in the ability of nutrients to make it from the mother's body -- through the vessels in the placenta -- to the baby. This, he says, can lead to "starvation" -- a point where the baby is dramatically losing nutrient support necessary for growth and development.
When this occurs, he says, either a miscarriage or stillbirth can be the result.
In this latest study, doctors gathered data on 24,768 singleton pregnancies between 1989 and 1996. Information about the mothers' alcohol intake, other lifestyle factors, maternal characteristics, and obstetric risk factors was garnered from questionnaires and hospital records.
The doctors then divided the women into two groups -- those who consumed less than one drink per week and those who consumed five or more drinks, with some of the women reporting as many as 14 drinks or more per week. The researchers then compared the pregnancy outcomes among all the women.
The risk for women who had five or more drinks during pregnancy was 2.96 times that of women who consumed less than one drink a week, the study says. At the higher level of drinking, the stillbirth rate was 8.83 per 1,000 births.
These numbers remained consistent even after the doctors made adjustments for possible confounding factors, including smoking, caffeine intake, age, pre-pregnancy body mass index, martial status, occupational status, education, number of previous children, and the sex of the child.
The increased risk of stillbirth was not associated with alcohol's link to increased risk of low birth weight, pre-term delivery, or birth defects.
Importantly, the deadly effects of alcohol were limited to unborn babies; there appeared to be no alcohol-related increased risk of death in infants born alive.
For Rebarber, the study is sound and the results convincing. However, he points out there appeared to be no consideration of whether the women used recreational drugs -- a factor that can independently increase the risk of stillbirth.
"The researchers were also relying on questionnaires that were filled out by the women themselves, which is not always the most reliable way to obtain data, particularly when it comes to habits like smoking, drinking and drug use," Rebarber says. Often, people tend to underestimate the amount of alcohol they consume or cigarettes they smoke.
In addition to increased risks of both miscarriage and stillbirth, other studies have shown alcohol can cause developmental delays in the form of fetal alcohol syndrome.
What To Do
For more information on the causes of stillbirth, visit the Stillbirth and Neonatal Death Society.
For a more personal look at the tragedy of stillbirth, go to Labor of Love.
