Disparities in gestational age-specific fetal mortality rates in the United States, 2009-2013

Purpose: Although studies have examined overall temporal changes in gestational age specific fetal mortality rates, there is little information on the current status of racial/ethnic differences. We hypothesize that differences exist between racial/ethnic groups across gestational age and that these differences are not equally distributed. Methods: Using the 2009-2013 data from US fetal death and live birth files for non-Hispanic white (NHW); non-Hispanic black (NHB); Hispanic; and American Indian/Alaska Native (ALAN) women, we conducted analyses to examine fetal mortality rates and estimate adjusted prevalence rate ratios and 95% confidence intervals (CIs). Results: There were lower risks of fetal mortality among NHB women (aPRR = 0.76; 95% CI = 0.71-0.81) and Hispanic women (aPRR = 0.89; 95% CI = 0.83-0.96) compared with NHWs at 22-23 weeks' gestation. For NHB women, the risk was higher starting at 32-33 weeks (aPRR = 1.11; 95% CI = 1.04-1.18) and continued to increase as gestational age increased. Hispanic and AIAN women had lower risks of fetal mortality compared with NHW women until 38-39 weeks. Conclusions: Further examination is needed to identify causes of fetal death within the later pregnancy period and how those causes and their antecedents might differ by race and ethnicity. (C) 2017 Elsevier Inc. All rights reserved.