BACKGROUND/PURPOSE: While recent evidence indicates increases in marijuana use among adult women in the United States (US), important questions remain with respect to marijuana use during pregnancy. This study examines trends and correlates of prenatal marijuana use and the effects of marijuana-specific risk/protective factors on marijuana use trends using a nationally representative sample.

METHOD

Data were derived from the National Survey on Drug Use and Health (2005-2014), a nationally representative survey that included 3640 married and 3987 unmarried pregnant women in the United States. The significance of marijuana use trends was tested using logistic regression analyses while adjusting for complex sampling design effects and controlling for sociodemographic and marijuana-specific factors.

RESULTS

From 2005-2014, marijuana use prevalence among unmarried pregnant women increased by 85% from 5.4% to 10.0% while the prevalence among married pregnant women remained stable (mostly under 1.5%). The increasing trend among unmarried pregnant women was associated with their lower disapproval and risk perceptions of marijuana use. In addition, past-year anxiety (AOR=3.30, 95% CI=1.87-5.82) and depression (AOR=3.85, 95% CI=2.33-6.36) diagnoses were linked with marijuana use among unmarried, but not married, pregnant women.

DISCUSSION

Increased attention should be paid to reducing prenatal marijuana use among unmarried women. Findings also suggest the need to attend to unmarried pregnant women's mental health problems as well as their physical health-risk behaviors.