Heavy Alcohol Consumption Increases Risk of Unintended Pregnancy While Cannabis Use Does Not

A recent study published in the journal Addiction has revealed that heavy alcohol consumption significantly raises the likelihood of unintended pregnancies among women who strongly wish to avoid pregnancy. The research analyzed data from over 2,000 women aged 15–34, focusing on a subgroup of 936 women expressing a high desire to prevent conception. Among these, 429 reported engaging in heavy drinking, while 362 used cannabis regularly, with 157 indicating daily use.

Findings showed that women who drank heavily had a 50% higher chance of becoming pregnant unintentionally compared to those who drank moderately or abstained from alcohol. Conversely, cannabis use did not correlate with an increased risk of unplanned pregnancy, with less than half of the undesired pregnancies occurring among women who used cannabis.

Over the course of a year, 71 women most motivated to avoid pregnancy became pregnant. Notably, 38 of these pregnancies occurred among heavy drinkers, highlighting the impact of alcohol on pregnancy risk. In contrast, only 28 pregnancies were among cannabis users, indicating no significant link between cannabis use and unintended pregnancies.

Lead researcher Dr. Sarah Raifman from the University of California, San Francisco, emphasized the importance of these findings. She stated that women who consume alcohol heavily tend to have a stronger desire to avoid pregnancy but are nonetheless at a higher risk of conception within a year. This suggests the need for targeted interventions and counseling.

Raifman also highlighted the potential risks associated with prenatal alcohol exposure, such as fetal alcohol spectrum disorders (FASD). Given the rising consumption of alcohol during pregnancy and its serious health implications, doctors and healthcare providers are encouraged to support women in reducing or stopping heavy drinking as soon as pregnancy is suspected.

This research underscores the importance of addressing alcohol use among women planning pregnancies and highlights that cannabis use does not appear to influence pregnancy intentions or risks.