Cannabis use, preterm birth, and small for gestational age: findings from the national birth defects prevention study

As the prevalence of cannabis use continues to increase among women of reproductive age, studies exploring the impact of in utero cannabis exposure on birth outcomes are warranted.

Using data from the National Birth Defects Prevention Study, logistic regression was used to assess the relationship between maternal self-report of cannabis use during early pregnancy and 1) preterm birth, and 2) being born SGA. Patterns of cannabis use during the first six months of pregnancy were also assessed.

Three percent of the sample (n = 324) reported cannabis use in early pregnancy. A slight majority (56%) of users ceased the use of cannabis after the second month of pregnancy. No significant association was observed between cannabis use and preterm birth (aOR = 1.27, 95% CI: 0.88-1.83) or SGA (aOR = 1.00, 95% CI: 0.68-1.47).

Cannabis use in early pregnancy was not significantly associated with preterm birth or SGA in this sample.