Race Disparities and Decreasing Birth Weight: Are All Babies Getting Smaller?
Race Disparities and Decreasing Birth Weight: Are All Babies Getting Smaller?
复制标题
DOI：
10.1093/aje/kwv194
复制
发表时间：
2016-01-01
影响因子：
5
通讯作者：
Simhan, Hyagriv N.
中科院分区：
文献类型：
--
作者：
Catov, Janet M.;Lee, MinJae;Simhan, Hyagriv N.
美国婴儿出生时的平均体重几十年来一直在增加，但现在可能正在下降。考虑到胎儿生长的种族差异，我们探讨了1997年至2011年宾夕法尼亚州匹兹堡Magee-Womens医院出生体重的种族特异性趋势。在37-41周的单胎分娩中（n = 70，607），我们评估了胎龄较小和胎龄较大的比例以及平均出生体重随时间的变化。结果按母亲人种/种族分层。自1997年以来，出生时小于胎龄的婴儿数量增加（8.7%-9.9%），而出生时大于胎龄的婴儿数量减少（8.9%-7.7%）。在调整出生孕周、母亲特征和妊娠条件后，出生体重每年下降2.20 g（P < 0.0001）。自然分娩的下降幅度更大。非裔美国妇女所生婴儿的减少显著大于白色妇女所生婴儿（每年-3.78 vs. -1.88;相互作用P = 0.010）。分位数回归模型表明，出生体重在整个分布中下降，但非洲裔美国妇女所生婴儿的体重下降仅限于考虑母体因素后的上四分位数。将分析限制在低风险女性中，消除了出生体重减轻。近年来，出生体重有所下降，非洲裔美国妇女所生婴儿的体重下降幅度更大。这些趋势可能是由于高血压和孕前肥胖等危险因素的积累，这些因素对非洲裔美国妇女的影响不成比例。我们的研究结果增加了胎儿生长中种族差异恶化的可能性。
The mean infant birth weight in the United States increased for decades, but it might now be decreasing. Given race disparities in fetal growth, we explored race-specific trends in birth weight at Magee-Womens Hospital, Pittsburgh, Pennsylvania, from 1997 to 2011. Among singleton births delivered at 37-41 weeks (n = 70,607), we evaluated the proportions who were small for gestational age and large for gestational age and changes in mean birth weights over time. Results were stratified by maternal race/ethnicity. Since 1997, the number of infants born small for their gestational ages increased (8.7%-9.9%), whereas the number born large for their gestational ages decreased (8.9%-7.7%). After adjustment for gestational week at birth, maternal characteristics, and pregnancy conditions, birth weight decreased by 2.20 g per year (P < 0.0001). Decreases were greater for spontaneous births. Reductions were significantly greater in infants born to African-American women than in those born to white women (-3.78 vs. -1.88 per year; P for interaction = 0.010). Quantile regression models indicated that birth weight decreased across the entire distribution, but reductions among infants born to African-American women were limited to those in the upper quartile after accounting for maternal factors. Limiting the analysis to low-risk women eliminated birth weight reductions. Birth weight has decreased in recent years, and reductions were greater in infants born to African-American women. These trends might be explained by accumulation of risk factors such as hypertension and prepregnancy obesity that disproportionately affect African-American women. Our results raise the possibility of worsening race disparities in fetal growth.