Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, Connecticut.
Paediatr Perinat Epidemiol. 2019 Sep;33(5):346-356. doi: 10.1111/ppe.12572. Epub 2019 Jul 31.
Preterm birth (PTB) disproportionately affects African American compared with Caucasian women, although reasons for this disparity remain unclear. Some suggest that a differential effect of maternal age by race/ethnicity, especially at older maternal ages, may explain disparities.
To determine whether the relationship between maternal age and preterm birth varies by race/ethnicity among primiparae non-Hispanic blacks (NHB) and non-Hispanic whites (NHW).
A cross-sectional study of 367 081 singleton liveborn first births to NHB and NHW women in California from 2008 to 2012 was conducted. Rate ratios (RR) were estimated for PTB and its subtypes-spontaneous and clinician-initiated-after adjusting for confounders through Poisson regression. Universal age/race reference groups (NHW, 25-29 years) and race-specific reference groups (NHW or NHB, 25-29 years) were used for comparisons.
Among all women, RR of PTB was highest at the extremes of age (<15 and ≥40 years). Among NHBs, the risk of PTB was higher than among NHWs at all maternal ages (adjusted RR of PTB 1.38-2.93 vs 0.98-2.38). However, using race-specific reference groups, the risk of PTB for NHB women (RR 0.91-1.88) vs NHW women (RR 0.98-2.39) was nearly identical at all maternal ages, with overlapping confidence intervals. Analyses did not demonstrate substantial divergence of risk with advancing maternal age. PTB, spontaneous PTB, and clinician-initiated PTB demonstrated similar risk patterns at younger but not older maternal ages, where risk of clinician-initiated PTB increased sharply for all women.
Primiparae NHBs demonstrated increased risk of PTB, spontaneous PTB, and clinician-initiated PTB compared with NHWs at all maternal ages. However, RRs using race-specific reference groups converged across maternal ages, indicating a similar independent effect of maternal age on PTB by race/ethnicity. A differential effect of maternal age does not appear to explain disparities in preterm birth by race/ethnicity.
早产（PTB）不成比例地影响非裔美国人和白种人女性，尽管造成这种差异的原因仍不清楚。有人认为，按种族/族裔划分的产妇年龄的差异，尤其是在较年长的产妇年龄，可能会解释这种差异。
确定非裔美国人和非裔美国黑人（NHB）和非西班牙裔白人（NHW）初产妇之间，产妇年龄与早产之间的关系是否因种族/族裔而异。
对 2008 年至 2012 年加利福尼亚州 367081 例单胎活产初产妇进行了横断面研究。通过泊松回归调整混杂因素后，估计早产及其亚型（自发性和临床医生发起的）的率比（RR）。使用通用年龄/种族参考组（NHW，25-29 岁）和特定种族参考组（NHW 或 NHB，25-29 岁）进行比较。
在所有女性中，年龄最小和最大（<15 岁和≥40 岁）的早产风险最高。在 NHB 中，与所有产妇年龄的 NHW 相比，PTB 的风险更高（调整后的 RR 为 1.38-2.93 比 0.98-2.38）。但是，使用特定种族参考组，NHB 女性（RR 0.91-1.88）与 NHW 女性（RR 0.98-2.39）的早产风险几乎相同，置信区间重叠。分析并未表明随着产妇年龄的增加，风险明显分化。在较年轻的产妇年龄中，PTB、自发性 PTB 和临床医生发起的 PTB 显示出相似的风险模式，但所有女性的临床医生发起的 PTB 风险急剧增加。
与 NHW 相比，所有产妇年龄的 NHB 初产妇 PTB、自发性 PTB 和临床医生发起的 PTB 的风险均增加。但是，使用特定种族参考组的 RR 在产妇年龄范围内趋于一致，表明种族/族裔对 PTB 的产妇年龄的独立影响相似。产妇年龄的差异似乎并不能解释种族/族裔之间的早产差异。
