A recent study found that the implementation of recreational cannabis laws in California was linked to higher rates of cannabis use during early pregnancy. The study was published in JAMA Health Forum.
Rates of cannabis use among pregnant women have significantly increased in recent years. This increase may be partly due to recreational cannabis legalization. Until now, epidemiological research examining recreational cannabis laws and prenatal cannabis use have been limited, and have produced conflicting results.
In the current study, researchers examined data from 300, 993 pregnancies collected between 2012 and 2019 from the Kaiser Permanente Northern California healthcare system with universal screening for cannabis use in early pregnancy. Data on prenatal cannabis use included urine toxicology test results and self-reports.
The researchers examined the data in light of the passage of California state recreational cannabis legislation in November 2016 and the implementation of legal sales in January 2018 with a one-month lag. They also examined the health data alongside local policies allowing or banning medical retailers pre-legalization and adult-use retailers post-legalization.
Before recreational cannabis law implementation, rates of prenatal cannabis use steadily rose from 4.5% in January 2012 to 7.1% in January 2018. They noted no change in usage rates after the passage of cannabis legalization in 2016; however, a month after laws were implemented, in February 2018, use significantly rose to 8.6%. Similar results were found whether defining prenatal cannabis use by a toxicology test or self-report.
From local policy analyses, the researchers found that increases in cannabis use post-legal implementation were only found among those living in jurisdictions that allowed adult-use cannabis retailers.
“Longer-term studies are needed to understand whether trends persist or change further over time. As legalization spreads across the US, it will be important to test whether local policies that prohibit or limit adult-use retailers moderate changes in prenatal cannabis use associated with state-level legalization,” concluded the researchers in their paper.
Sources: EurekAlert, JAMA Health Forum