July 31, 2014 — Summary of "Assessing Preventability of Maternal Mortality in Illinois: 2002-2012," Geller et al., American Journal of Obstetrics & Gynecology, June 20, 2014.
Although the U.S. maternal mortality rate decreased dramatically in the 20th century, it "has nearly tripled over the last quarter century," according to researchers led by Stacie Geller of the University of Illinois College of Medicine's Center for Research on Women and Gender. The researchers serve on the Illinois Department of Public Health Maternal Mortality Review Committee Working Group.
While reasons for the increase in maternal mortality are not completely known, studies suggest that about half of the nearly 650 pregnancy-related deaths in the U.S. each year are from preventable causes, the researchers noted.
The researchers sought to assess the potential preventability of maternal deaths in Illinois, where the state "require[s] the reporting and review of all deaths to women within a year of pregnancy, regardless of cause of death." The reviews are conducted by the state's network of Regionalized Perinatal Centers, which determine whether the death was possibly preventable. The state defines maternal deaths as those "caused by direct or indirect complications of pregnancy."
Specifically, the researchers examined records on maternal deaths from the Illinois Department of Public Health's Maternal Mortality Review Form database for 2002 to 2012. The database "includes demographics, characteristics of the pregnancy and delivery/termination, determination of cause of death as related to pregnancy, and an assessment of the potential preventability of the death and identification of avoidable factors (patient, provider or systems)," the researchers explained.
For the study, maternal mortality ratio was defined as the number of women who died from a pregnancy-related cause during pregnancy or within 42 days afterward, "divided by the number of live births multiplied by 100,000." The researchers noted that deaths directly related to pregnancy -- such as those resulting from obstetrical complications -- and deaths indirectly related to pregnancy -- such as those stemming from a pre-pregnancy condition -- are both considered pregnancy-related deaths.
The researchers then analyzed associations between the causes of death and possible preventability of pregnancy-related deaths.
The study identified 610 maternal deaths in Illinois from 2002 to 2012.
One-third (210) of the deaths were pregnancy-related, 7.1% (43) were possibly related, and 52.6% (321) were not related to pregnancy. The researchers calculated a maternal mortality ratio of 10.5 maternal deaths per 100,000 live births.
More than 80% of all maternal deaths (509) occurred in women ages 20 to 39. Almost 50% of the deaths occurred among non-Hispanic white women, 35.3% occurred among non-Hispanic black women and 11.5% were among Hispanic women.
About two-thirds of the deaths occurred at hospitals, while the others occurred at women's residences or "other locations such as the site of a car accident," the researchers wrote. Twenty-one percent of the women died while pregnant and two-thirds died postpartum, mostly at more than 42 days postpartum.
The most common cause of pregnancy-related death was vascular issues, followed by cardiac causes and hemorrhage. One-third of pregnancy-related deaths were possibly preventable. Deaths associated with hemorrhage or psychiatric causes were most commonly deemed preventable, "while cancer and vascular-related deaths were generally not considered preventable," the researchers wrote.
According to Geller and colleagues, their findings in Illinois are similar to analyses in other states.
"In order to reduce maternal mortality and morbidity, states should review the causes and preventability of pregnancy-deaths," the researchers wrote. They noted that previous research has found that "30-50% of these cases are potentially preventable," which is consistent with their findings in Illinois.
Reducing "preventable pregnancy-related deaths can be achieved through the use of a multi-tiered approach addressing provider, system and patient-related factors," according to the researchers.
They concluded, "Efforts aimed at addressing these factors have the greatest potential to improve the delivery and coordination of obstetric care, possibly leading to improved overall maternal health in the state of Illinois."