Some states that have legalized recreational cannabis have enacted policies mandating that signs warning about harms from using cannabis during pregnancy (MWS-cannabis) are to be posted in places where cannabis is sold. But new findings from a study show that the mandatory warning signs for cannabis policies are not based in evidence.
This study aimed to examine the relationship between enacting MWS-cannabis and adverse birth outcomes. To do so, the researchers took advantage of a quasi-experiment where Washington State enacted MWS-cannabis and nearby states did not. They used a Difference-in-Differences framework to compare changes in birth outcomes in Washington State to changes in birth outcomes in comparison states before and after Washington State enacted MWS-cannabis in June 2016. This study stems from a larger project examining MWS-cannabis birth outcomes and attitudes towards pregnant people's cannabis use.
Past research has shown MWS for alcohol use during pregnancy is associated with increases in adverse birth outcomes. Now, similar outcomes are associated with enacting MWS for cannabis use during pregnancy, showing that they do not provide public health benefit. Policymakers should be cautious about enacting MWS-cannabis policies.
The article, Relationship between mandatory warning signs for cannabis use during pregnancy policies and birth outcomes in the Western United States, is available in Preventive Medicine.