According to a report from nine Maternal Mortality Review Committees (MMRCs), 60 percent of pregnancy-related deaths are preventable. The reason for these unnecessary deaths and the overall rise in maternal mortality cannot be definitively understood, specifically due to the overall lack of explicit and conclusive data. From a medical standpoint, common causes of maternal death include: cardiomyopathy, cardiovascular and coronary conditions, hemorrhage, and infection.
Cardiomyopathy is a disease of the heart muscle that impedes it from effectively pumping blood to the rest of the body, potentially leading to heart failure. Pregnancy places additional strain on the body and the heart, exemplified by doubled heart output and increased heart rate (by 15 percent). Thus, any pre-existing or pregnancy-induced cardiac conditions (such as cardiovascular disease) can worsen under this increased physiological burden. Yet, these complications may not be immediately visible at the beginning of a pregnancy and may not immediately stop once the baby is born. According to the Center for Disease Control and Prevention (CDC), between 2011 to 2014 cardiomyopathy and cardiovascular disease led to 10.3 percent and 15.2 percent of pregnancy-related deaths, respectively. 68 percent of these cardiovascular and coronary maternal deaths have been deemed preventable.
Hemorrhage can occur for several reasons such as: placental issues (i.e. placenta accreta and placenta previa), uterine rupture, or tears. Between 2011 to 2014, hemorrhage accounted for 11.5 percent of pregnancy-related deaths. According to a report by nine MMRCs, 70 percent of hemorrhage-caused deaths were considered preventable.
Postpartum infections stem from a variety of factors including: C-sections, forceps delivery, prolonged or obstructed labor, malnutrition, anemia, and preterm birth. Delivery in a low-resource setting poses additional risk of postpartum infection. These initial infections can lead to sepsis, as the body undergoes chemical changes in an attempt to combat the pathogen. The CDC concluded that infection (or sepsis) led to 12.8 percent of pregnancy-related deaths from 2011 to 2014.
Other Potential Factors:
When analyzing broad trends in maternal mortality rates, factors beyond the strictly physiological must be considered. As mentioned in a previous post, procedural changes in the reporting of maternal deaths occurred on both a federal and a state level. As a result, higher rates of maternal mortality were reported after the adoption of a death certificate in line with the national one. This phenomenon is exemplified by a Maryland study, which demonstrated that the ability to identify maternal deaths was much higher (98 percent versus 62 percent) after specific pregnancy questions were added to a death certificate. Thus, this improved data collection may be contributing to the trend of rising reported maternal mortality. Nevertheless, there are definitively other factors largely responsible for the observed increase of maternal mortality, which MMRCs aim to investigate and identify.
Some have postulated that the increasing prevalence of Caesarian sections factors into the rising maternal death rate. There are multiple reasons why Caesarian sections should be considered for delivery. However, Caesarian sections can come with additional risks. According to birth cohorts studied by MacDorman et. al. (2006), neonatal mortality was more prevalent among infants delivered by Caesarian section in comparison to vaginal birth (1.77 versus 0.62 per 1,000 live births). Solheim et. al. (2011) determined the rate of Caesarians sections performed has been rising steadily since 1996. In fact, the study predicts that, by 2020, there will be a Caesarian delivery rate of 56.2 percent.
Though the causality behind the rising rates of maternal mortality has yet to be conclusively determined, there are undeniable disparities with regards to maternal death. There is a clear disparity in maternal outcomes with regards to age, socioeconomic status, and race. According to the CDC, National Center for Health Statistics, and National Vital Statistics system, the rate of maternal death increases with age. While, for pregnant women under 20 years of age, there are 7.1 instances of maternal mortality (per 100,000 live births), the number jumps to 32.3 for mothers 35 years and older.
In addition to age, socioeconomic status also impacts the rate of maternal mortality. In a study by the U.S. Department of Health and Human Services, participants’ data from various counties was divided into three financially-based categories: a low poverty group (less than 5 percent of families in a county are below the poverty line), a middle poverty group (5 to 14.999 percent), and a high poverty group (15 percent or greater). In comparison to the low poverty group, the middle and high poverty groups had increased rates of maternal mortality by 58 and 102 percent, respectively.
In all economic categories, African American women had a maternal mortality risk approximately 3 times higher than their Caucasian counterparts, indicating that racial disparity in maternal outcomes transcends economic class. According to the American College of Obstetricians and Gynecology, maternal death occurs in 7 of 100,000 live births for Caucasian women. However, for African American women, 26 of 100,000 live births result in mortality. Yet, this disparity is not geographically homogenous; African American women residing in New York City are 12 times more likely to experience maternal mortality than Caucasian women.