Each week a woman consumes alcohol during the first five to 10 weeks of pregnancy is associated with an 8% increase, according to a new studyRisk of miscarriagetied together.
The results were published in the “American Journal of Obstetrics and Gynecology.” Researchers at Vanderbilt University Medical Center (VUMC) are studying the timing, amount and type of alcohol consumption during pregnancy and the relationship between these factors and the risk of miscarriage before 20 weeks of pregnancy.
The effects of alcohol consumption increase in the 9th week of pregnancy, and the risk increases regardless of whether a woman reports drinking less than one or more than four drinks per week. The risk is also independent of the type of alcohol consumed and whether the woman has had episodes of binge drinking.
Although most women change their alcohol consumption after a positive pregnancy test, drinking alcohol before a pregnancy is detected is common among both planned and pregnant womenan unwanted pregnancyusual. Half of the 5,353 women included in the analysis reported alcohol consumption around the time of conception and during the first weeks of pregnancy.
The median gestational age (length of pregnancy already achieved) for stopping alcohol consumption was 29 days. Although 41% of women changed their drinking within three days of a positive pregnancy test, those who stopped drinking near their last menstrual period had a 37% higher risk of miscarriage than women who did not consume alcohol.
“Avoiding alcohol during conception or pregnancy has long been recommended for many reasons, including preventing fetal alcohol syndrome (FAS). “Still, moderate alcohol consumption is often considered safe,” said Dr. Katherine Hartmann, principal investigator and vice president for research integration at VUMC.
“For this reason, our results are alarming. The level of alcohol consumption that women and some doctors consider responsible is harmful, and no amount of alcohol can be described as safe in relation to miscarriage”.
The study recruited women planning to become pregnant or in early pregnancy from eight metropolitan areas in Tennessee, North Carolina and Texas. Participants were asked about their alcohol consumption during the first trimester of pregnancy.
According to the researchers, one in six recognized pregnancies ends in miscarriage. Biologically, little is known about how alcohol causes harm during early pregnancy, but it may increase the risk of miscarriage by altering hormonal patterns or the quality of egg implantation or by increasing oxidative stress.
Because alcohol is most commonly consumed in the first few weeks - when the embryo is developing most rapidly and establishing the pattern for organ development - it is important to understand how timing relates to miscarriage risk.
To avoid an increased risk of miscarriage, researchers emphasize the importance of using home pregnancy tests that can detect pregnancy as early as possible. This allows women to stop drinking alcohol immediately if they are planning to become pregnant or if pregnancy is possible.
