Abstract：
OBJECTIVE: To investigate the association between infant mortality and birth weight using estimated fetal weight (EFW) versus birth-weight charts, by gestational age (GA).
METHODS: This nationwide population-based study used data from the Finnish Medical Birth Register from 2006 to 2016 on non-malformed singleton live births at 24-41+6 weeks of gestation (N = 563 630). The outcome was death in the first year of life. Mortality risks by birth-weight z score, defined as a continuous variable using Maršál\'s EFW and Sankilampi\'s birth-weight charts, were assessed using generalized additive models by GA (24-27+6, 28-31+6, 32-36+6, 37-38+6, 39-41+6 weeks). We calculated z score thresholds associated with a two- and three-fold increased risk of infant death compared with newborns with a birth weight between 0 and 0.675 standard deviations.
RESULTS: The z score thresholds (with corresponding centiles in parentheses) associated with a two-fold increase in infant mortality were: -3.43 (<0.1) at 24-27+6 weeks, -3.46 (<0.1) at 28-31+6 weeks, -1.29 (9.9) at 32-36+6 weeks, -1.18 (11.9) at 37-38+6 weeks, and - 1.34 (9.0) at 39-41+6 weeks according to the EFW chart. These values were - 2.43 (0.8), -2.62 (0.4), -1.34 (9.0), -1.37 (8.5), and - 1.43 (7.6) according to the birth-weight chart.
CONCLUSIONS: The association between birth weight and infant mortality varies by GA whichever chart is used, suggesting that different thresholds for the screening of growth anomalies could be used across GA to identify high-risk newborns.
METHODS: This nationwide population-based study used data from the Finnish Medical Birth Register from 2006 to 2016 on non-malformed singleton live births at 24-41+6 weeks of gestation (N = 563 630). The outcome was death in the first year of life. Mortality risks by birth-weight z score, defined as a continuous variable using Maršál\'s EFW and Sankilampi\'s birth-weight charts, were assessed using generalized additive models by GA (24-27+6, 28-31+6, 32-36+6, 37-38+6, 39-41+6 weeks). We calculated z score thresholds associated with a two- and three-fold increased risk of infant death compared with newborns with a birth weight between 0 and 0.675 standard deviations.
RESULTS: The z score thresholds (with corresponding centiles in parentheses) associated with a two-fold increase in infant mortality were: -3.43 (<0.1) at 24-27+6 weeks, -3.46 (<0.1) at 28-31+6 weeks, -1.29 (9.9) at 32-36+6 weeks, -1.18 (11.9) at 37-38+6 weeks, and - 1.34 (9.0) at 39-41+6 weeks according to the EFW chart. These values were - 2.43 (0.8), -2.62 (0.4), -1.34 (9.0), -1.37 (8.5), and - 1.43 (7.6) according to the birth-weight chart.
CONCLUSIONS: The association between birth weight and infant mortality varies by GA whichever chart is used, suggesting that different thresholds for the screening of growth anomalies could be used across GA to identify high-risk newborns.
摘要：
目的：使用估计胎儿体重（EFW）与出生体重图，调查婴儿死亡率与出生体重之间的关系。胎龄（GA）。
方法：这项全国性的基于人群的研究使用了2006年至2016年芬兰医学出生登记册中关于妊娠24-41+6周非畸形单胎活产的数据（N=563630）。结果是生命的第一年死亡。按出生体重z评分计算的死亡率风险，使用Maršál的EFW和Sikilampi的出生体重图表定义为连续变量，通过GA使用广义累加模型进行评估（24-276，28-316，32-366，37-386，39-416周）。我们计算了与出生体重在0和0.675标准差之间的新生儿相比，婴儿死亡风险增加2倍和3倍的z评分阈值。
结果：与婴儿死亡率增加两倍相关的z评分阈值（括号中相应的百分位数）在24-27+6周为-3.43（<0.1），-3.46（<0.1）在28-31+6周，-1.29（9.9）在32-36+6周，-1.18（11.9）在37-38+6周，根据EFW图表，39-41+6周时-1.34(9.0)。这些值为-2.43（0.8），-2.62（0.4），-1.34（9.0），-1.37（8.5），和-1.43（7.6），根据出生体重表。
结论：出生体重与婴儿死亡率之间的关联因GA使用的图表而异，这表明可以在GA中使用不同的生长异常筛查阈值来识别高危新生儿.
方法：这项全国性的基于人群的研究使用了2006年至2016年芬兰医学出生登记册中关于妊娠24-41+6周非畸形单胎活产的数据（N=563630）。结果是生命的第一年死亡。按出生体重z评分计算的死亡率风险，使用Maršál的EFW和Sikilampi的出生体重图表定义为连续变量，通过GA使用广义累加模型进行评估（24-276，28-316，32-366，37-386，39-416周）。我们计算了与出生体重在0和0.675标准差之间的新生儿相比，婴儿死亡风险增加2倍和3倍的z评分阈值。
结果：与婴儿死亡率增加两倍相关的z评分阈值（括号中相应的百分位数）在24-27+6周为-3.43（<0.1），-3.46（<0.1）在28-31+6周，-1.29（9.9）在32-36+6周，-1.18（11.9）在37-38+6周，根据EFW图表，39-41+6周时-1.34(9.0)。这些值为-2.43（0.8），-2.62（0.4），-1.34（9.0），-1.37（8.5），和-1.43（7.6），根据出生体重表。
结论：出生体重与婴儿死亡率之间的关联因GA使用的图表而异，这表明可以在GA中使用不同的生长异常筛查阈值来识别高危新生儿.
