March of Dimes Prematurity Research Center at Stanford University School of Medicine, Stanford, CA, USA.
Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, CA, USA.
J Perinatol. 2019 Sep;39(9):1175-1181. doi: 10.1038/s41372-019-0402-1. Epub 2019 Jun 17.
Short interpregnancy interval (IPI) is associated with adverse pregnancy outcomes, including preterm birth (PTB < 37 weeks GA). We investigated whether short IPI (< 6 months) contributes to the higher PTB frequency among non-Hispanic Blacks (NHB).
Using a linked birth cohort > 1.5 million California live births, we examined frequencies of short IPI between racial/ethnic groups and estimated risks by multivariable logistic regression for spontaneous PTB. We expanded the study to births 1991-2012 and utilized a "within-mother" approach to permit methodologic inquiry about residual confounding.
NHB women had higher frequency (7.6%) of short IPI than non-Hispanic White (NHW) women (4.4%). Adjusted odds ratios for PTB and short IPI were 1.64 (95% CI 1.54, 1.76) for NHW and 1.49 (1.34, 1.65) for NHB. Using within-mother analysis did not produce substantially different results.
Short IPI is associated with PTB but does not explain risk disparity between NHWs and NHBs.
妊娠间隔时间过短（IPI）与不良妊娠结局相关，包括早产（GA<37 周）。我们研究了非西班牙裔黑人（NHB）中早产频率较高是否与 IPI 过短（<6 个月）有关。
我们使用了一个超过 150 万例加利福尼亚活产儿的链接出生队列，检查了不同种族/族裔群体之间的 IPI 过短频率，并通过多变量逻辑回归估计了自发性早产的风险。我们将研究扩展到 1991-2012 年的分娩，并采用“母亲内”方法，以允许对残余混杂进行方法学研究。
NHB 女性的 IPI 过短频率（7.6%）高于非西班牙裔白人（NHW）女性（4.4%）。调整后的早产和 IPI 过短比值比（OR）分别为 1.64（95%CI 1.54,1.76）和 1.49（1.34,1.65）。使用母亲内分析并未产生明显不同的结果。
IPI 过短与早产相关，但不能解释 NHW 和 NHB 之间的风险差异。
