Racial and ethnic disparities in birth Outcomes: A decomposition analysis of contributing factors

This study seeks to quantify and rank the contribution of selected factors to the observed racial/ethnic disparities in low-birth-weight births (LBWBs) and preterm births (PTBs). Based on vital statistics data on births to primiparous women and characteristics of mothers in the State of Nebraska during the period of 2005 to 2014 (n = 93,375), unadjusted and adjusted odds ratios were estimated to examine the association between selected variables and the odds of having LBWBs or PTBs. Fairlie decomposition analysis was performed to quantify the contribution of each selected factor to racial/ethnic differences in LBWB and PTB rates. The prevalence of PTBs was 9.1% among non-Hispanic White (NHW) women, as compared to 12.8% among non-Hispanic Black (NHB) women and 10.6% among Hispanic women. The corresponding prevalence of LBWBs in the three groups were 5.9%, 11.9%, and 7.2%, respectively. The higher educational attainment among NHW women, relative to NHB women accounted for 10% of the observed difference in LBWB rate between the two groups. Health insurance coverage was the second most important factor accounting for the observed disparities in birth outcomes. Addressing socioeconomic disadvantages in NHB and Hispanic women would be important for them to narrow their gaps with NHW women in LBWB and PTB prevalence. More research is needed to identify key factors leading to the disparities in birth outcomes between NHW and NHB women.