Cannabis use in pregnancy may raise infant health risks

A large study of more than 360,000 mothers and infants found increased risk of low birth weight and admission to the neonatal intensive care unit (NICU) for babies whose mothers used cannabis during pregnancy.

The findings align with previous research suggesting a connection between prenatal cannabis use and low birthweight babies, and advice from the American College of Obstetricians and Gynecologists that pregnant patients avoid cannabis in pregnancy.

The researchers also found a “dose-response” relationship, meaning increasing risk of infant health risks with more frequent reported use of cannabis.

The analysis used health records from 364,924 infants born to Kaiser Permanente Northern California (KPNC) members between January 2011 and July 2020. Of these, 6.2% of the infants were exposed to cannabis in utero. Information about cannabis use was obtained from a self-report prenatal screening questionnaire and a urine toxicology test.

The study found statistically significantly greater odds of low birthweight, baby that is small for gestational age, preterm birth, and admission to a NICU. 

“Our analysis adds new concerns about the potential for preterm birth and NICU admission, which are associated with immediate, highly stressful situations for the family as well as long-term adverse outcomes for the child,” said lead author Lyndsay Avalos, PhD, MPH, a research scientist with the Kaiser Permanente Division of Research.

About Kaiser Permanente
Kaiser Permanente is committed to helping shape the future of health care. We are recognized as one of America’s leading health care providers and not-for-profit health plans. Founded in 1945, Kaiser Permanente has a mission to provide high-quality, affordable health care services and to improve the health of our members and the communities we serve. We currently serve 12.7 million members in 8 states and the District of Columbia. Care for members and patients is focused on their total health and guided by their personal Permanente Medical Group physicians, specialists, and team of caregivers. Our expert and caring medical teams are empowered and supported by industry-leading technology advances and tools for health promotion, disease prevention, state-of-the-art care delivery, and world-class chronic disease management. Kaiser Permanente is dedicated to care innovations, clinical research, health education, and the support of community health.