Ray Joel G, Berger Howard, Aoyama Kazuyoshi, Cook Jocelynn L, Aflaki Kayvan, Park Alison L
Departments of Medicine and Obstetrics and Gynaecology St. Michael's Hospital, University of Toronto, 30 Bond Street, Toronto, ON, M5B 1W8, Canada.
ICES, Toronto, ON, Canada.
Matern Health Neonatol Perinatol. 2025 Jul 3;11(1):19. doi: 10.1186/s40748-025-00217-8.
There is a reverse J-shaped relation between newborn weight percentile and risk of perinatal mortality. Perinatal mortality itself is associated with severe maternal morbidity and mortality (SMM-M) around the index pregnancy, likely because the two share common etiologies, including placental dysfunction. We evaluated an infant's birthweight percentile and risk of its mother experiencing SMM-M.
This population-based cohort study was completed within a universal healthcare system in Ontario, Canada. Included were 2,203,490 singleton livebirths between 2002 and 2020. The study exposure was infant birthweight percentile for gestational age and sex. The 25th to 75th percentile served as the referent. The main outcome was SMM-M arising from 23 week's gestation up to 42 days postpartum. Multivariable modified Poisson regression generated relative risks (aRRs) and 95% confidence intervals (CI), adjusted for maternal age, income, rurality, pre-existing diabetes and hypertension.
A J-shaped relation was seen between birthweight and risk of SMM-M. Relative to the 25th to 75th (15.0 per 1000 livebirths), the aRR of SMM-M was 1.27 (95% CI 1.21, 1.32) at 5th to < 10th, 1.40 (95% CI 1.28, 1.53) at 2nd to < 3rd, and 1.48 (95% CI 1.36, 1.62) at < 1st birthweight percentile. At higher birthweights, the aRR was 1.16 (95% CI 1.11, 1.21) at 90th to < 95th, 1.24 (95% CI 1.13, 1.36) at 95th to < 96th, and 1.73 (95% CI 1.60, 1.87) at > 99th percentile.
There is a J-shaped relation between infant birthweight and risk of its mother experiencing SMM-M, likely due to shared risk factors and a common pathogenesis.
新生儿体重百分位数与围产期死亡率之间存在倒J形关系。围产期死亡率本身与本次妊娠期间的严重孕产妇发病和死亡（SMM-M）相关，这可能是因为两者具有共同的病因，包括胎盘功能障碍。我们评估了婴儿的出生体重百分位数及其母亲发生SMM-M的风险。
这项基于人群的队列研究在加拿大安大略省的全民医疗保健系统内完成。纳入了2002年至2020年间的2,203,490例单胎活产。研究暴露因素为根据胎龄和性别划分的婴儿出生体重百分位数。第25至75百分位数作为对照。主要结局是妊娠23周起至产后42天内发生的SMM-M。多变量修正泊松回归分析得出相对风险（aRR）和95%置信区间（CI），并对产妇年龄、收入、居住在农村地区、既往糖尿病和高血压进行了校正。
出生体重与SMM-M风险之间呈J形关系。相对于第25至75百分位数组（每1000例活产中有15.0例），出生体重在第5至<10百分位数时SMM-M的aRR为1.27（95%CI 1.21, 1.32），第2至<3百分位数时为1.40（95%CI 1.28, 1.53），<第1百分位数时为1.48（95%CI 1.36, 1.62）。在出生体重较高时，第90至<95百分位数时aRR为1.16（95%CI 1.11, 1.21），第95至<96百分位数时为1.24（95%CI 1.13, 1.36），>第99百分位数时为1.73（95%CI 1.60, 1.87）。
婴儿出生体重与其母亲发生SMM-M的风险之间呈J形关系，这可能是由于共同的风险因素和发病机制所致。
