Research Activities February 2013, No. 390
Factors linked to racial or ethnic disparities in U.S. fetal death rates differ among groups
The fetal death rates for all hospital deliveries occurring over more than a decade in three large States (3.3 per 1,000 deliveries overall) are higher for black women, Asian women, and Hispanic women (5.9, 3.2, and 3.6 per 1,000 deliveries, respectively) than for white women (2.6 per 1,000 deliveries), according to a new study. It also found that black women had the highest rate of low and very-low-birth-weight deliveries (often associated with fetal death) compared to the other racial/ethnic groups.
Black and Asian women had high rates of certain complications that increase fetal death risk, such as small-for-gestational age fetuses and inflammation of the fetal membranes, compared with women from other racial or ethnic groups. In addition, black women had a higher prevalence of placental disorders and pregnancy-induced hypertension, both of which were associated with a higher risk of fetal death.
When the possible mediating factors for fetal death were classified as socioeconomic factors, antepartum/intrapartum complications of pregnancy, or fetal factors, the researchers found different patterns of impact by each racial/ethnic group. Socioeconomic factors accounted for 15.7 percent of the difference in fetal death rate for black women, while ante- and intrapartum complications accounted for 29.7 percent, and fetal factors (birth weight, multiple gestation, and small-for-gestational age) accounted for 49.6 percent, leaving an unexplained disparity of 5.0 percent.
Socioeconomic factors accounted for 35.8 percent of the disparity for Hispanic women, while the other two categories had no significant impact, leaving 64.2 percent residual disparity. For Asian women, socioeconomic and ante/intrapartum complications accounted for 37.8 percent and 62.2 percent of the disparity, respectively, leaving 3.4 percent of factors related to fetal death unexplained. The findings were based on data on 7.1 million hospital deliveries in California, Missouri, and Pennsylvania between January 1, 1995, and June 30, 2005 and analysis of 23,471 fetal deaths. The study was supported in part by the Agency for Healthcare Research and Quality (HS15696).
More details are in "Factors that mediate racial/ethnic disparities in US fetal death rates," by Scott A. Lorch, M.D., M.S.C.E., Charlan D. Kroelinger, Ph.D., Corinne Ahlberg, M.S., and others in the October 2012 American Journal of Public Health 102(10), pp. 1902-1910.