Impact of reproductive laws on maternal mortality: the chilean natural experiment

Abstract

Improving maternal health and decreasing morbidity and mortality due to induced abortion are key endeavors in developing countries. One of the most controversial subjects surrounding interventions to improve maternal health is the effect of abortion laws. Chile offers a natural laboratory to perform an investigation on the determinants influencing maternal health in a large parallel time-series of maternal deaths, analyzing health and socioeconomic indicators, and legislative policies including abortion banning in 1989. Interestingly, abortion restriction in Chile was not associated with an increase in overall maternal mortality or with abortion deaths and total number of abortions. Contrary to the notion proposing a negative impact of restrictive abortion laws on maternal health, the abortion mortality ratio did not increase after the abortion ban in Chile. Rather, it decreased over 96 percent, from 10.8 to 0.39 per 100,000 live births. Thus, the Chilean natural experiment provides for the first time, strong evidence supporting the hypothesis that legalization of abortion is unnecessary to improve maternal health in Latin America.

Keywords: Abortion; Fertility paradox; Maternal health; Maternal mortality; Women education.

Figure 1.

Trends in the absolute number of maternal deaths (A), live births in thousands (B), and stillbirths in thousands (C). Data based on official records from the National Institute of Statistics, Chile, 1909–2009.

Figure 2.

Historical trend of MMR year-by-year in Chile from 1909–2009. Dark gray bars identify the period of highest increase on maternal mortality between 1931 and 1937. (Koch et al., interim analyses: unpublished material from the Chilean Maternal Mortality Research Initiative CMMRI).

Figure 3.

Trends for MMR and AMR after abortion ban in Chile. A continuous decreasing trend can be observed for MMR (A) and AMR (B) between 1979 and 2009. Since abortion prohibition, MMR decreased from 40.8 to 16.9 per 100,000 live births. The accumulated decrease between 1989 and 2009 was 58 percent. AMR decreased from 10.8 to 0.4 per 100,000 live births. The accumulated decrease for the period was 96 percent.

Figure 4.

Impact of different factors on MMR based on pathway modeling using ARIMA. The dark area in the each bar illustrates the synergistic effect of the increasing women's educational level on the impact of any other variable.

Figure 5.

Main causes of maternal deaths in Chile and Mexico during 2009.