Paternal Marijuana Use Linked to Miscarriage Risk

A male partner's use of marijuana at least once a week has been found to be associated with increased risk of miscarriage in pregnancy, according to research being presented this week at the Scientific Congress of the American Society for Reproductive Medicine.

A prospective cohort study used data from the Pregnancy Study Online to examine male partners' pre-conception marijuana use patterns, with frequency of use in the two months prior to conception categorized as no use, use less than once a week, and use once or more a week. The study from researchers at the Boston University School of Public Health found that couples with male partners who used marijuana at least once a week had a greater risk of miscarriage compared with those where the male partner used no marijuana. Little association with miscarriage risk was seen in the group where male partners used marijuana less frequently.

“There have long been concerns about the impact of marijuana on sperm quality,” Harris Nagler, MD, president of the Society for Male Reproduction and Urology, said in a news release about the study results. “As the legal landscape changes, it is important that we do more of this kind of research to help us counsel our patients.”

The association between more frequent marijuana use and risk of spontaneous abortion persisted after adjusting for reproductive history, and was slightly stronger when the analysis was restricted to couples where the female partner did not use marijuana.