Evaluating the effects of recreational cannabis policies on prenatal cannabis use and maternal and child health outcomes for real-world impact

About This Grant

PROJECT SUMMARY Cannabis use among pregnant women has increased more than 60% over the past decade. Up to 15% of women use cannabis prior to pregnancy and 6% prenatally, with differences by demographics, mental health symptoms, polysubstance use, and area-level factors. While evidence is building on the detrimental effects of cannabis use on adverse birth outcomes, the consequences of prenatal use on women's health during pregnancy or postpartum or on child health outcomes remains under-studied. The cannabis policy context has been evolving rapidly with 24 states and DC having legalized recreational cannabis. Significant gaps remain in understanding the effects of legalization on prenatal cannabis use and spillover effects on other substances, birth outcomes, maternal and child health outcomes, and provider assessment of use as well as variations in policy effects across individual- and area-level factors. The state of Maine provides an important natural experiment to understand the contextual landscape and trajectory of cannabis use among pregnant women. Maine legalized recreational cannabis in January 2017 and introduced retail sales in October 2020; municipalities were required to opt-in, providing staggered retail sales across the 16 counties. We propose a novel data linkage between Maine Pregnancy Risk Assessment Monitoring System 2016-2023 state-representative cohorts with birth certificates, All-Payer Claims Data and hospital health insurance claims to collate 6 years of data on each pregnant woman (N=6,307) and resulting child(ren) from 2 years prior to conception to 3 years postpartum, covering 2014-2026. With individual-level data and county-level identifiers, we will rigorously evaluate the effects of state- and county-level recreational cannabis policies on women's cannabis, tobacco, and alcohol use (referred to as substance use) before, during, and after pregnancy and, subsequently, on birth outcomes and maternal and child health outcomes. This project has three Specific Aims. Aim 1 will quantify the effects of state recreational cannabis legalization and county retail sales on women's substance use and health outcomes. Aim 2 will quantify the downstream effects of state recreational cannabis legalization and county retail sales on birth outcomes and child health outcomes. Aim 3 will examine the differential effects of state recreational cannabis legalization and county retail sales across demographic (race/ethnicity, education, health insurance status, age) and higher-risk (depression, polysubstance use) strata and area-level (rural/urban, federal poverty level) factors across Aims 1 and 2. The cannabis policy landscape is evolving rapidly. Study findings will (a) fill critical gaps in understanding the unintended consequences of emerging cannabis policies on pregnant women, birth outcomes, and maternal and child health; and (b) inform dissemination strategies that translate findings to guide policy and public health responses and inform clinical practice to protect the health of vulnerable mothers and children.