Pilliod Rachel A, Page Jessica M, Sparks Teresa N, Caughey Aaron B
a Department of Obstetrics and Gynecology , Oregon Health and Science University , Portland , OR , USA.
b Department of Obstetrics and Gynecology , University of Utah , Salt Lake City , UT , USA.
J Matern Fetal Neonatal Med. 2019 Feb;32(3):442-447. doi: 10.1080/14767058.2017.1381904. Epub 2017 Oct 3.
To compare fetal/infant mortality risk associated with each additional week of expectant management with the infant mortality risk of immediate delivery in growth-restricted pregnancies.
A retrospective cohort study was conducted of singleton, nonanomalous pregnancies from the 2005-2008 California Birth Registry comparing pregnancies affected and unaffected by growth restriction, defined using birth weights as a proxy for fetal growth restriction (FGR). Birth weights were subdivided as greater than the 90th percentile, between the 10th percentile and 90th percentile, and less than the 10th percentile. Cases greater than the 90th percentile were excluded from analysis. Cases less than the 10th percentile were considered to have FGR and were further subcategorized into <10th percentile, <5th percentile, and <3rd percentile. We compared the risk of infant death at each gestational age week against a composite risk representing the mortality risk of one additional week of expectant management.
We identified 1,641,000 births, of which 110,748 (6.7%) were less than 10th percentile. The risk of stillbirth increased with gestational age with the risk of stillbirth at each week of gestation inversely proportional to growth percentile. The risks of fetal and infant mortality with expectant management outweighed the risk of infant death for all FGR categories analyzed beginning at 38 weeks. However, the absolute risks differed by growth percentiles, with the highest risks of infant death and stillbirth in the <3rd percentile cohort. At 39 weeks, absolute risks were low, although the number needed to deliver to prevent 1 death ranged from 413 for <3rd percentile to 2667 in unaffected pregnancies.
At 38 weeks, the mortality risk of expectant management for one additional week exceeds the risk of delivery across all growth-restricted cohorts, despite variation in absolute risk by degree of growth restriction.
比较在生长受限妊娠中，期待治疗每增加一周所带来的胎儿/婴儿死亡风险与即刻分娩的婴儿死亡风险。
对2005 - 2008年加利福尼亚州出生登记处的单胎、非畸形妊娠进行回顾性队列研究，比较受生长受限影响和未受影响的妊娠，使用出生体重作为胎儿生长受限（FGR）的替代指标来定义生长受限。出生体重分为大于第90百分位数、在第10百分位数和第90百分位数之间以及小于第10百分位数。大于第90百分位数的病例被排除在分析之外。小于第10百分位数的病例被认为患有FGR，并进一步细分为<第10百分位数、<第5百分位数和<第3百分位数。我们将每个孕周的婴儿死亡风险与代表期待治疗额外一周的死亡风险的综合风险进行比较。
我们确定了1,641,000例出生病例，其中110,748例（6.7%）小于第10百分位数。死产风险随孕周增加，妊娠各周的死产风险与生长百分位数成反比。对于所有分析的FGR类别，从38周开始，期待治疗的胎儿和婴儿死亡风险超过了婴儿死亡风险。然而，绝对风险因生长百分位数而异，<第3百分位数队列中的婴儿死亡和死产风险最高。在39周时，绝对风险较低，尽管为预防1例死亡所需的分娩数从<第3百分位数的413例到未受影响妊娠的2667例不等。
在38周时，尽管绝对风险因生长受限程度而异，但所有生长受限队列中期待治疗额外一周的死亡风险超过了分娩风险。
