Pregnant women’s alcohol use is correlated with their partners’ drinking, according to a large European study — and partners are unlikely to meaningfully reduce or halt their alcohol consumption while expecting a baby. The findings may offer a new way of identifying women at risk of drinking in pregnancy and potentially intervening to prevent or reduce harm. Alcohol consumption during pregnancy can seriously impair fetal health and development, causing stillbirth and lifelong disabilities. These include fetal alcohol spectrum disorders (FASDs), the primary cause of non-genetic cognitive disability worldwide. Although the drinking patterns of women and their partners are known to be correlated, little attention has been given to partners’ alcohol use during pregnancy and how this may affect women’s drinking and pregnancy outcomes. For the study in Alcoholism: Clinical & Experimental Research, investigators searched for associations between pregnant women’s and their partners’ alcohol use before and during pregnancy.

Researchers worked with 14,800 women during 21,500 singleton pregnancies in Finland, 2009–2018, a sample representative of the pregnant and parenting population in that country. During the study period, two in three participants gave birth once, the others twice or more. The researchers collected information on the pregnant women and partners using electronic questionnaires and during clinical visits. They used a diagnostic scale to retrospectively evaluate the risk of problematic alcohol use before pregnancy, and statistical analysis to explore links between the women’s and their partners’ drinking over time.

In 82% of births, the women were engaged, married, or cohabiting with partners. In 86% of pregnancies, women reported using alcohol before pregnancy; for one in ten participants, this included binge drinking twice a month or more. The women’s alcohol use before pregnancy correlated strongly with their partners’ frequency of drinking, frequency of binge drinking, weekly amounts consumed, and alcohol-use risk scores. Most of the women terminated their drinking during pregnancy, though women reported drinking in 4.5% of pregnancies. In one in four cases, the woman stopped drinking only after recognizing that she was pregnant, raising the possibility of alcohol exposure early in pregnancy. Younger women (up to age 26) reported the riskiest drinking before pregnancy, though during pregnancy their alcohol consumption was similar to that of the older women. Overall, partners’ alcohol use during pregnancy declined only slightly, and none reportedly stopped drinking. During pregnancy, the correlations between the women’s and the partners’ alcohol use weakened but remained significant. For example, among pregnant women who drank, the amount of alcohol they consumed was related to their partners’ drinking patterns. Women who reported using alcohol in pregnancy were generally heavier drinkers before pregnancy, suggesting the possibility of alcohol dependency.

The findings support assessing all prospective parents’ alcohol use and encouraging reductions in drinking before pregnancy to avoid unintentional prenatal exposure. Interventions such as counseling both parents on the harms of fetal alcohol exposure, and highlighting partners’ role in supporting pregnant women, may help reduce women’s drinking during pregnancy.