The costs, benefits, and cost-effectiveness of interventions to reduce maternal morbidity and mortality in Mexico

Abstract

Background: In Mexico, the lifetime risk of dying from maternal causes is 1 in 370 compared to 1 in 2,500 in the U.S. Although national efforts have been made to improve maternal services in the last decade, it is unclear if Millennium Development Goal 5--to reduce maternal mortality by three-quarters by 2015--will be met.

Methodology/principal findings: We developed an empirically calibrated model that simulates the natural history of pregnancy and pregnancy-related complications in a cohort of 15-year-old women followed over their lifetime. After synthesizing national and sub-national trends in maternal mortality, the model was calibrated to current intervention-specific coverage levels and validated by comparing model-projected life expectancy, total fertility rate, crude birth rate and maternal mortality ratio with Mexico-specific data. Using both published and primary data, we assessed the comparative health and economic outcomes of alternative strategies to reduce maternal morbidity and mortality. A dual approach that increased coverage of family planning by 15%, and assured access to safe abortion for all women desiring elective termination of pregnancy, reduced mortality by 43% and was cost saving compared to current practice. The most effective strategy added a third component, enhanced access to comprehensive emergency obstetric care for at least 90% of women requiring referral. At a national level, this strategy reduced mortality by 75%, cost less than current practice, and had an incremental cost-effectiveness ratio of $300 per DALY relative to the next best strategy. Analyses conducted at the state level yielded similar results.

Conclusions/significance: Increasing the provision of family planning and assuring access to safe abortion are feasible, complementary and cost-effective strategies that would provide the greatest benefit within a short-time frame. Incremental improvements in access to high-quality intrapartum and emergency obstetric care will further reduce maternal deaths and disability.

Figure 1. Schematic of Natural History Model.

Upper Panel. The ovals represent the key health states used in the model. Nonpregnant 15-year-old women enter the model and are subject to an annual risk of pregnancy. Once pregnant, a woman may experience a miscarriage, elect to undergo an abortion, develop a maternal complication, or have an uncomplicated pregnancy and delivery. A small proportion of nonpregnant women will have severe anemia and subsequently will have a higher risk of mortality from maternal complications. Lower Panel. Every pregnant woman is subject to a risk of developing major maternal complications, such as a sexually transmitted infection with chlamydia or gonorrhea, sepsis, postpartum hemorrhage, severe preeclampsia/eclampsia, or obstructed labor. Each maternal complication is associated with a further risk of death or long-term sequelae (e.g., infertility, severe anemia, neurological sequelae, rectovaginal fistula), which are associated with a decrement in health-related quality of life and costs related to either management or treatment.

Figure 2. Schematic of Modeled Interventions.

Interventions are applied to different points along the clinical course of pregnancy and delivery. Prenatal care, the treatment of sexually transmitted infections, and the management of severe anemia apply throughout the three trimesters of pregnancy prior to labor and delivery. Safe abortion applies to the first trimester of pregnancy. Hospital-based interventions such as the management of severe preeclampsia/eclampsia, obstructed labor, postpartum hemorrhage, and sepsis apply to the periods of labor and delivery as well as postpartum.

Figure 3. The Impact of Costs Invested in Enhancing Access to EmOC.

The additional costs required to enhance access to comprehensive EmOC, expressed as the composite cost of a successfully referred woman, is assumed to include the costs required for ensuring recognition of the need for referral, expedient transport, and ultimate access to an appropriate facility capable of comprehensive EmOC. Shown is the impact of varying the cost per successfully referred woman from $18.50 to $370, on the incremental cost-effectiveness ratios (ICER) for a strategy that includes (1) an increase in family planning from 59% to 74% in women age 20 and older, and from 18% to 33% in women younger than age 20, (2) access to safe abortion for all women who electively terminate a pregnancy; and (3) access to high-quality intrapartum care for all pregnant women and enhanced access to comprehensive emergency obstetric care for at least 90% of women (pink line), compared with a strategy only focusing on family planning and safe abortion. Also shown is the impact on the total lifetime savings for a cohort of 100,000 women that could be achieved using this strategy as compared to current practice in Mexico (blue line). Provided the incremental cost was below $120 per successfully referred woman, the most effective strategy would be associated with a lower average per-woman lifetime cost than that of current practice (green dashed line). Even at a cost of $185 per successfully referred woman (red solid line), the incremental cost-effectiveness ratio was less than the Mexico-specific GDP per capita, and would be considered very cost-effective.