Department of Medicine, Solna, Clinical Epidemiology Unit, Karolinska Institutet, Stockholm, Sweden.
Department of Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada.
BJOG. 2018 Jul;125(8):973-981. doi: 10.1111/1471-0528.15034. Epub 2017 Dec 28.
To study the association between total and early pregnancy (<22 completed weeks) weight gain and risk of stillbirth, stratified by early-pregnancy body mass index (BMI).
Population-based cohort study.
Stockholm-Gotland Region, Sweden.
Pregnant women with singleton births (n = 160 560).
Pregnancy weight gain was standardised into gestational age-specific z-scores. For analyses of total pregnancy weight gain, a matched design with an incidence density sampling approach was used. Findings were also contrasted with current Institute of Medicine (IOM) weight gain recommendations.
Stillbirth defined as fetal death at ≥22 completed weeks of gestation.
For all BMI categories, there was no statistical association between total or early pregnancy weight gain and stillbirth within the range of a weight gain z-score of -2.0 SD to +2.0 SD. Among normal-weight women, the adjusted odds ratio of stillbirth for lower (-2.0 to -1.0 SD) and higher (+1.0 to +1.9 SD) total weight gain was 0.85 (95% CI; 0.48-1.49) and 1.03 (0.60-1.77), respectively, as compared with the reference category. Further, there were no associations between total or early pregnancy weight gain and stillbirth within the range of weight gain currently recommended by the IOM. For the majority of the BMI categories, the point estimates at the extremes of weight gain values (<-2.0SD and ≥2.0 SD) suggested protective effects of low weight gain and increased risks of high weight gain, but estimates were imprecise and not statistically significant.
We found no associations between total or early pregnancy weight gain and stillbirth across the range of weight gain experienced by most women.
There was no association between weight gain during pregnancy and stillbirth among most women.
研究总孕期体重增加（<22 周）和早期孕期体重增加（<22 周）与死产风险的关系，并按早期孕期体重指数（BMI）分层。
基于人群的队列研究。
瑞典斯德哥尔摩-歌德堡地区。
单胎妊娠的孕妇（n=160560）。
妊娠体重增加被标准化为特定胎龄的 z 分数。对于总孕期体重增加的分析，使用匹配设计和发生率密度抽样方法。研究结果还与当前的医学研究所（IOM）体重增加建议进行了对比。
死产定义为妊娠 22 周及以上的胎儿死亡。
在所有 BMI 类别中，在体重增加 z 分数范围为-2.0 SD 至+2.0 SD 内，总孕期体重增加或早期孕期体重增加与死产之间没有统计学关联。在正常体重的女性中，较低（-2.0 至-1.0 SD）和较高（+1.0 至+1.9 SD）总体重增加的调整后死产比值比分别为 0.85（95%CI：0.48-1.49）和 1.03（0.60-1.77），与参考组相比。此外，在 IOM 目前建议的体重增加范围内，总孕期体重增加或早期孕期体重增加与死产之间也没有关联。对于大多数 BMI 类别，体重增加值极端（< -2.0SD 和≥2.0 SD）的点估计值表明低体重增加具有保护作用，而高体重增加的风险增加，但估计值不准确，且无统计学意义。
我们发现，在大多数女性经历的体重增加范围内，总孕期体重增加或早期孕期体重增加与死产之间没有关联。
在大多数女性中，孕期体重增加与死产之间没有关联。
