High alcohol intake is associated with decreased female fertility, says a recent study.

Women who drink 14 or more servings of alcohol a week are slightly more likely to have reduced fertility, suggests a study published by The British medical Journal. Low to moderate intake of alcohol, defined as one to seven servings a week, seemed to have no effect on women’s fertility, nor did the type of alcohol beverage consumed. But the authors still recommend for couples to abstain from alcohol during their fertile window until a pregnancy is ruled out, because the foetus may be particularly vulnerable to alcohol during the first few weeks after conception.

In developed countries, up to 24 percent of couples experience infertility, defined as time to pregnancy of 12 months or more. Official guidelines in several countries, including Australia, recommend that women trying to become pregnant should abstain from alcohol consumption. But the extent to which alcohol intake affects female fertility is unclear. So a group of Danish researchers carried out a large study to examine the association between pre-conception alcohol consumption and time to pregnancy. In total, 6,120 female Danish residents, aged 21-45 years, were included. They were all in a stable relationship with a male partner, trying to conceive and not receiving fertility treatment.

The study assessed overall alcohol consumption as well as intake of specific types of alcoholic beverages. Each woman completed bimonthly questionnaires for 12 months, or until conception occurred, on alcohol use, pregnancy status, menstrual cycles, frequency of intercourse, and smoking. In women who drank 14 or more servings of alcohol a week, there were 37 pregnancies in 307 cycles, compared with 1381 pregnancies in 8054 cycles in women who did not drink.