Minority women have a disproportionate risk of serious complications during delivery, according to researchers from the Centers for Disease Control and Prevention in Atlanta, Georgia; Brigham and Women’s Hospital; and Harvard Medical School, both in Boston, Massachusetts. Whereas maternal death has been the “traditional sentinel event” for monitoring maternal health, they say, maternal morbidity is more common.
The researchers used data from > 90% of all births between 2008 and 2010 in 7 states: Arizona, California, Florida, Michigan, New Jersey, New York, and North Carolina. Of nearly 3.5 million delivery hospitalizations, 43% were among non-Hispanic whites, 33% Hispanics, 13% non-Hispanic blacks, 7% Asian/Pacific Islanders, 0.6% American Indian/Alaska Native women, and 4.3% other or multiple race/ethnicity groups. The researchers analyzed the rates of morbidity indicators, including blood transfusion, heart failure during procedure or surgery, ventilation, eclampsia, shock, and sepsis.
Blood transfusion was the most common indicator of severe morbidity with rates ranging from about 79 to 187 per 10,000 delivery hospitalizations among non-Hispanic white and non-Hispanic black women, respectively. Overall, for every 10,000 delivery hospitalizations, 151 involved at least 1 severe complication (114 non-Hispanic whites, 284 non-Hispanic blacks). Non-Hispanic black women had 2.1 times higher rates of severe morbidity (measured with blood transfusion), compared with non-Hispanic white women. American Indian/Alaskan Native women had 1.7 times higher rates, Hispanic women had 1.3 times, and Asian/Pacific Islander women had 1.2 times higher rates.
Some indicators in particular stood out. In earlier analyses, the researchers say, they had found that “traditional” causes of pregnancy-related deaths (such as hemorrhage and sepsis) had given way to cardiovascular disease, cardiomyopathy, and other medical conditions. Those data were borne out by this study’s findings. For instance, 22 of the 25 specific severe morbidity indicators were significantly higher among non-Hispanic black women than that among non-Hispanic white women (all P < .05); notably, the rate of cardio monitoring was > 20 times higher than that among non-Hispanic white women. That finding, the researchers believe, points to significant differences in mortality rates contributed by cardiovascular conditions, especially cardiomyopathy, between U.S.-born black and white women. Cardiovascular-specific mortality ratios were 5.1 and 1.9 deaths per 100,000 live births, respectively. And as in other studies, this study found a rate 3 to 4 times higher for in-hospital maternal mortality among non-Hispanic black women.
Clinically, the researchers say their findings suggest a need for better screening. They advise combining maternal race and ethnicity with other maternal characteristics and obstetric history to get a clearer picture of the clinical risk for adverse outcomes.
Creanga AA, Bateman BT, Kuklina EV, Callaghan WM. Am J Obstet Gynecol. 2014;210:435.e1-435.e8.