Study: 1 in 6 Michigan moms use pot while pregnant

OG article by Dan Chalk

December 29, 2025

A Michigan State University study reveals that at least one in six pregnant women in Michigan use marijuana during pregnancy, with results published in the January 2026 issue of Addiction. The research, led by epidemiologist Ban Al-Sahab, used urine samples to track cannabis use among expectant mothers statewide and found unmarried women twice as likely as married women to use it, alongside higher rates among those with less education. Central Michigan University Professor Beth Bailey, a developmental psychologist and maternal child health expert, aligns these findings with her mid-Michigan research, noting patterns of lower head circumference, shorter stature in exposed babies, and elevated body mass index by age 3. Her 2023 CMU study in Frontiers in Pediatrics highlighted first-trimester effects on fetal growth. Bailey emphasizes that modern marijuana's THC potency has increased tenfold due to commercialization post-legalization in 2018, shifting effects from minimal to significant compared to pre-2012 research, often confounded by tobacco co-use. She warns that legalization fosters perceptions of safety, necessitating enhanced public health education, especially for unplanned pregnancies (50% of cases), to inform women early. Healthcare providers must address substance use comprehensively, using marijuana discussions as entry points to tackle more harmful tobacco exposure. Education of future physicians on these dangers is critical for better outcomes.