Drinking alcohol during the first three months of pregnancy has been linked to an increased risk of premature birth or "unexpectedly small babies."
The U.K. Department of Health recommends completely cutting out alcohol during pregnancy and even when trying to conceive; most middle-aged women drink more than this, a British Medical Journal news release reported.
The research team looked at 1,264 questionnaires taken by women who had a low risk of birth complications. The mothers were asked how often they consumed alcohol and what kind they drank at four different points in time: "in the four weeks before conception; and in each of the subsequent three months (trimesters) throughout the pregnancy" the news release reported.
The researchers found alcohol consumption was significantly higher before conception and in the first three months of pregnancy than in the last two trimesters. The rate of consumption averaged at 11 units per week before conception; four during early pregnancy; and under two during the later trimesters.
The U.K. Department of Health includes abstaining for alcohol during pregnancy, but recommends no more than two units per week. Fifty-three percent of the women in the study consumed over that recommended weekly maximum during the first trimester. About four out of 10 women admitted they drank more than 10 units a week while trying to conceive.
Those who drank more than two units per week were more likely to be "older, educated to degree level, of white ethnicity, and more likely to live in affluent areas," the news release reported.
The team found a significant link between alcohol consumption during the first three weeks of pregnancy and an increased risk of premature or underweight birth. Even women who did not exceed the recommended two units per week maximum still had an increased risk of these complications. Drinking while trying to conceive was also associated with "restricted fetal growth."
"Our results highlight the need for endorsing the abstinence-only message, and further illuminate how timing of exposure is important in the association of alcohol with birth outcomes, with the first trimester being the most vulnerable period," the authors wrote, the news release reported.
