Why do pregnant women die? A review of maternal deaths from 1990 to 2010 at the University of Alabama at Birmingham.

Background: The number of reported pregnancy-related deaths in the United States steadily increased from 7.2 deaths per 100,000 live births in 1987 to a high of 17.8 deaths per 100,000 live births in 2009. Compared to Caucasian women, African American women were nearly 4 times as likely to die from childbirth. To better understand the reason for this trend, we conducted a case-control study at University of Alabama at Birmingham (UAB) Hospital. Our primary study hypothesis was that women who died at UAB were more likely to be African American than women in a control group who delivered an infant at UAB and did not die. We expected to find a difference in race proportions and other patient characteristics that would further help to elucidate the cause of a racial disparity in maternal deaths.

Methods: We reviewed all maternal deaths (cases) at UAB Hospital from January 1990 through December 2010 identified based on electronic uniform billing data and ICD-9 codes. Each maternal death was matched 2:1 with women who delivered at a time that most closely coincided with the time of the maternal death in 2-step selection process (electronic identification and manual confirmation). Maternal variables obtained were comorbidities, duration of hospital stay, cause of death, race, distance from home to hospital, income, prenatal care, body mass index, parity, insurance type, mode of delivery, and marital status. The strength of univariate associations of maternal variables and case/control status was calculated. The association of case/control status and race was also examined after controlling for residential distance from the hospital.

Results: There was insufficient evidence to suggest racial disparity in maternal death. The proportion of African American women was 57% (42 of 77) in the maternal death group and 61% (94 of 154) in the control group (P = 0.23). The univariate odds ratio for maternal death for African American to Caucasian race was 0.66 (95% confidence interval [CI], 0.37-1.19); the adjusted odds ratio was 1.46 (95% CI, 0.73-3.01). Longer compared with shorter distance of residence to the hospital was a highly significant predictor (P < 0.001) of maternal death.

Conclusions: We did not observe a racial disparity in maternal deaths at UAB Hospital. We suggest that the next step toward understanding racial differences in maternal deaths reported in the United States should be directed at the health care delivery outside the tertiary care hospital setting, particularly at eliminating access barriers to health care for all women.