Department of Obstetrics and Gynecology, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
Perinatal Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
J Perinatol. 2019 Sep;39(9):1190-1195. doi: 10.1038/s41372-019-0394-x. Epub 2019 May 14.
To quantify racial differences in contribution of previable live births (<20 weeks gestational age (GA)) to United States (US) Infant Mortality Rates (IMR).
Population-based retrospective cohort of US live births (2007-14) using CDC WONDER database stratified by maternal race/ethnicity. We compared the contribution of previable births to IMR and calculated modified IMRs (≥20 weeks GA) excluding previable live births in each group. Contingency tables and chi-square calculations were performed to detect differences between groups.
Previable deaths represented 4.1%, 7.7%, and 5.0% of total deaths for nonHispanic white, nonHispanic black, and Hispanic, respectively. Previable contribution to total IMR are 0.21, 0.89, and 0.26 per 1000 live births (P < 0.0001). Modified IMRs are 4.98, 10.85, and 4.69 deaths per 1000 live births.
IMR standardization with a minimum GA may obscure the disproportionate contribution of previable births to IMRs among the black population, which has the largest proportion of previable births.
量化美国（US）婴儿死亡率（IMR）中，各种族间早产活产儿（<20 周妊娠龄（GA））的贡献差异。
本研究采用 CDC WONDER 数据库，基于美国活产儿（2007-14 年）的人群回顾性队列研究，按照产妇种族/族裔进行分层。我们比较了早产活产儿对 IMR 的贡献，并计算了每个组中排除早产活产儿后的改良 IMR（≥20 周 GA）。使用列联表和卡方检验来检测组间差异。
非西班牙裔白人、非西班牙裔黑人和西班牙裔的早产死亡分别占总死亡的 4.1%、7.7%和 5.0%。早产对总 IMR 的贡献分别为每 1000 例活产儿 0.21、0.89 和 0.26（P<0.0001）。改良 IMR 分别为每 1000 例活产儿 4.98、10.85 和 4.69 例死亡。
采用最小 GA 进行 IMR 标准化可能会掩盖黑人中早产活产儿对 IMR 不成比例的贡献，而黑人的早产活产儿比例最大。
