Prenatal Cannabis Exposure May Disrupt Reproductive Development Across Generations

A recent study conducted by Washington State University reveals that cannabis use during pregnancy and nursing can have lasting effects on the reproductive health of female offspring, extending even to subsequent generations. The research, published in Toxicological Sciences, involved exposing female mice to vaporized cannabis extract from the start of pregnancy until their offspring were weaned. The findings showed that females directly exposed to cannabis produced smaller litters, experienced delayed puberty, and had irregular reproductive cycles. Notably, these effects were most pronounced in the first generation and became less severe in the second, with no significant symptoms observed by the third generation.

While the study indicated that cannabis exposure did not influence pregnancy duration, litter size, or survival rates, the early developmental delays observed in first-generation females suggest a direct impact on reproductive maturation. This highlights concerns about the safety of cannabis use during pregnancy, despite its legal status in 24 U.S. states and Washington, D.C. Cannabis remains the most widely used recreational drug in the country, with over 48 million users annually. However, health authorities like the American College of Obstetricians and Gynecologists strongly advise against its use during pregnancy and breastfeeding due to risks such as low birth weight and impaired brain development.

The researchers replicated human consumption by exposing female mice to vaporized cannabis twice daily throughout pregnancy and lactation, then analyzing outcomes across three generations. Interestingly, the study showed that maternal reproductive parameters remained unaffected, suggesting that the reproductive delays are likely due to developmental disruptions caused by cannabis exposure rather than pregnancy complications.

In addition to its direct effects, the study emphasizes the importance of considering mixed substance use during pregnancy, as many women also consume alcohol, tobacco, or other drugs. Her team is now exploring whether male offspring are similarly impacted, with preliminary results indicating more severe reproductive effects in males.

The findings underscore the need for awareness around the potential long-term reproductive consequences of cannabis use during pregnancy and the importance of ongoing research in this area.

For more details, see the original publication: Mingxin Shi et al, Transgenerational effects of perinatal cannabis exposure on female reproductive parameters in mice, Toxicological Sciences (2025). DOI: 10.1093/toxsci/kfaf043.