Prenatal Cannabis Exposure Modestly Associated With Decreased Birth Weight

Cannabis use is becoming more prevalent in the US, including among persons who are pregnant. Moreover, the potency of cannabis has been increasing. This raises concerns about the potential effect of prenatal cannabis exposure (PCE) on birth outcomes. Researchers used data from the Michigan Archive for Research on Child Health from 2017 to 2022 to prospectively investigate the association between PCE and birth outcomes while adjusting for other factors.

• Of the 584 pregnant persons in the cohort, 90 (15 percent) reported cannabis use during pregnancy. Those who reported use were younger, more likely to identify as non-Hispanic Black, to report high school as their highest level of education, or to have government insurance; they were less likely to be obese, smoke tobacco, or use alcohol.
• In adjusted analyses, PCE was associated with lower birth weight (ß = −0.3), but not with other measured birth outcomes: pre-term birth, gestational age, five-minute Apgar score, and neonatal intensive care unit admission.

Comments: This study shows an association between PCE and modestly lower birth weights, but not other birth outcomes. This information can be used to counsel persons who are pregnant or may potentially become pregnant.

Darius A. Rastegar, MD

Reference: Vanderziel A, Anthony JC, Barondess D, et al. Estimating the effects of prenatal cannabis exposure on birth outcomes. Am J Addict. 2025;34(1):21-29.