Impact of State-Level Changes on Maternal Mortality: A Population-Based, Quasi-Experimental Study

Background/Purpose: Reports that maternal mortality rates in the US continue to climb are in stark contrast to historical US declines as well as falling global trends. Maternal mortality rates are 3-4 times higher for black women than white or Hispanic women. Recent increases and persistent disparities have led to speculation about why the US has higher maternal mortality rates than most high-income countries.

Women are entering pregnancy in poorer health, while political and economic changes may be affecting family planning and reproductive health services. Over the last decade, the US has witnessed a changing political, economic, and social climate related to women’s reproductive health. State policies and programs related to women’s access to family planning and reproductive health services may directly or indirectly affect maternal mortality rates. However, to our knowledge, whether these changes are contributing to the increase in maternal mortality remains unknown. Our aim was to examine the impact of changes in state-level factors plausibly linked to maternal mortality on overall rates and by race/ethnicity.

Methods: Data and samples: We used the 2007-2015 National Vital Statistics System microdata mortality files from 38 states and DC. The primary exposures were five state-level sexual and reproductive health indicators (Number of Planned Parenthood clinics, laws restricting abortions based on gestational age, requiring abortion providers to obtain admitting privileges, restricting coverage for abortion in Marketplace insurance; maternal mortality review committee) and six health and economic conditions (obesity prevalence, cesarean section prevalence, unemployment rate, percentage of Medicaid recipients, Medicaid expansion, HRSA funding rate). The maternal mortality rate was defined as death of a woman while pregnant or within 42 days of termination of pregnancy per 100,000 live births. We estimated a difference-in-differences zero-inflated negative binomial regression model to examine the impact of state-level factors on maternal mortality rates, using the race/ethnicity-age-state-year population as the denominator and adjusting for race/ethnicity, age, state, and year. We subsequently tested interactions with each sexual and reproductive health indicator and race/ethnicity. 

Results: There were 4,767 deaths among women up to age 44 years resulting in a maternal mortality rate of 17.9 per 100,000 live births. The maternal mortality rate for black women was 3 times higher (39.9) than the rate for white (13.8) or Hispanic (13.2) women. We found that reducing the proportion of Planned Parenthood clinics by 20% from the state-year mean increased the maternal mortality rate by 8% (IRR 1.08; 95% CI 1.04-1.12). States that enacted legislation to restrict abortions based on gestational age increased the maternal mortality rate by 38% (IRR 1.38; 1.03-1.84). Planned Parenthood clinic closures negatively impacted all women, increasing mortality by 6-15% across racial/ethnic groups. While gestational limits primarily increased mortality among white women (IRR 1.56; 1.13-1.98), rates were elevated across all racial/ethnic groups.

Conclusions and Implications: Recent fiscal and legislative changes reducing women’s access to family planning and reproductive health services have contributed to rising maternal mortality rates. In order to improve maternal outcomes we need to move beyond short-term political decisions and consider their longer-term, evidence-based impact on women’s health.