Impacts of Medicaid Expansion Before Conception on Prepregnancy Health, Pregnancy Health, and Outcomes.

Preconception health care is heralded as an essential method of improving pregnancy health and outcomes. However, access to health care for low-income US women of reproductive age has been limited because of a lack of health insurance. Expansions of Medicaid program eligibility under the Affordable Care Act (as well as prior expansions in some states) have changed this circumstance and expanded health insurance coverage for low-income women. These Medicaid expansions provide an opportunity to assess whether obtaining health insurance coverage improves prepregnancy and pregnancy health and reduces prevalence of adverse pregnancy outcomes. We tested this hypothesis using vital statistics data from 2011-2017 on singleton births to female US residents aged 15-44 years. We examined associations between preconception exposure to Medicaid expansion and measures of prepregnancy health, pregnancy health, and pregnancy outcomes using a difference-in-differences empirical approach. Increased Medicaid eligibility was not associated with improvements in prepregnancy or pregnancy health measures and did not reduce the prevalence of adverse birth outcomes (e.g., prevalence of preterm birth increased by 0.1 percentage point (95% confidence interval: -0.2, 0.3)). Increasing Medicaid eligibility alone may be insufficient to improve prepregnancy or pregnancy health and birth outcomes. Preconception programming in combination with attention to other structural determinants of pregnancy health is needed.