Mike: Hello, I'm Mike Clarke, podcast editor for the Cochrane Library. The topics for some Cochrane Reviews cut across multiple Review Groups. This is the case with an April 2024 review of interventions to stop or reduce alcohol consumption during pregnancy, which is relevant to both Cochrane Pregnancy and Childbirth and Drugs and Alcohol. Here’s one of the authors, Julia Sinclair from the University of Southampton in the UK to tell us more.

Julia: Alcohol (ethanol) is a small molecule that, once it is absorbed into the blood stream can reach every organ of the body, including the womb. There, it can affect the developing foetus, which is highly sensitive to toxins.
Alcohol is widely consumed in many societies, and although most people drink at levels that are considered relatively low risk, it is now accepted that there is no ‘safe level’ of alcohol consumption, particularly during pregnancy. Harms from alcohol include direct and indirect effects on physical and mental health, as well as wider negative impacts on the individual and society. The harms caused by alcohol to the pregnant person or unborn child vary widely, dependent on the amount and pattern of exposure to alcohol over the course of the pregnancy.
This is the first systematic review specifically investigating the effects of any kind of treatment, including drugs, psychosocial or educational interventions to achieve abstinence from alcohol or reduce alcohol consumption during pregnancy. We looked at the effects on various outcomes, including the number or rate of participants who achieved abstinence, number or rate of abstinent days, alcohol consumed per week, and scores on validated questionnaires.
We found eight randomised studies involving nearly 1400 women who reported any alcohol use when pregnant. There were six studies from the USA, one from Spain and the other was conducted in the Netherlands. In two studies, almost half the participants were diagnosed with a current or previous alcohol use disorder. All the studies focussed on the efficacy of psychosocial interventions (mainly brief interventions) for helping pregnant women to achieve and maintain abstinence, or at least reduce their alcohol use during pregnancy.
We found that the brief psychosocial interventions increased the rate of pregnant women reaching and maintaining continuous abstinence. However, the evidence was more uncertain about the effects on the number of drinks consumed per day. Finally, we found that the addition of a brief intervention to treatment as usual duing pregnancy resulted in little to no difference in the number of women who completed treatment, which is positive.
Unfortunately, though, the small number and variability across the studies in types of participant, intervention and measurement of outcome limit our confidence in these findings. We hope that this will be improved by future studies and that these will provide detailed information on alcohol use before and during pregnancy using consistent alcohol consumption measures, such as the number of drinks per drinking day.

Mike: Thanks Julia. If you would like to read more about the current evidence and watch for an update to the review if the new studies become available, just go to CochraneLibrary.com and search ‘alcohol during pregnancy’.