Department of Medicine, Solna, Clinical Epidemiology Unit and
Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, Canada.
Am J Clin Nutr. 2016 May;103(5):1278-84. doi: 10.3945/ajcn.115.110197. Epub 2016 Mar 23.
Pregnancy weight-gain z score charts have recently been proposed as a new tool for classifying gestational weight gain and establishing the link between weight gain and adverse maternal and infant outcomes. However, existing charts are few in number, were based on small sample sizes, and were not population based.
We created population-based pregnancy weight-gain-for-gestational-age z score charts for Swedish women who were stratified by early pregnancy body mass index (BMI).
Serial prenatal electronic medical records were obtained from women who were receiving obstetrical care in the Swedish counties of Gotland and Stockholm. The study population was restricted to nonanomalous, singleton, term pregnancies with no prepregnancy hypertension or diabetes. A multilevel linear regression was used to express the repeated weight-gain measurements as a function of gestational age in underweight, normal-weight, overweight, and obese class I-III women. Observed weight-gain ranges were contrasted with current Institute of Medicine (IOM) pregnancy weight-gain recommendations.
A total of 711,615 serial prenatal weight measurements from 141,767 pregnant women were included. The smoothed means, SDs, and selected percentiles (3rd, 10th, 50th, 90th, and 97th) of weight gain were estimated for each week of gestation. The total weight gain and rate of weight gain decreased with increasing prepregnancy BMI. In all BMI categories, the observed range of pregnancy weight gain was considerably broader than the range currently recommended by the IOM.
The presented population-based pregnancy weight-gain charts can be used to express maternal weight gain as gestational age-standardized z scores with early pregnancy BMI taken into consideration. The z scores can be used to obtain a better understanding of the relation between pregnancy weight gain and maternal and infant health complications.
最近提出了妊娠体重增长 z 评分图表作为一种新的工具，用于对妊娠体重增加进行分类，并建立体重增加与母婴不良结局之间的联系。然而，现有的图表数量较少，基于小样本量，并且不是基于人群的。
我们为瑞典妇女创建了基于人群的妊娠体重增长与胎龄 z 评分图表，并按早孕体重指数（BMI）分层。
从接受瑞典哥特兰和斯德哥尔摩县产科护理的妇女中获得了连续的产前电子病历。研究人群仅限于无异常、单胎、足月妊娠，且无孕前高血压或糖尿病。使用多水平线性回归将重复体重增加测量值表示为低体重、正常体重、超重和肥胖 I-III 级妇女的胎龄函数。观察到的体重增加范围与当前美国医学研究所（IOM）的妊娠体重增加建议进行了对比。
共纳入了 141767 名孕妇的 711615 次连续产前体重测量值。估计了每个孕周的体重增加的平滑均值、标准差和选定的百分位数（第 3、10、50、90 和 97 个百分位数）。体重增加的总增量和增重率随早孕 BMI 的增加而降低。在所有 BMI 类别中，观察到的妊娠体重增加范围明显宽于 IOM 目前建议的范围。
本研究提供的基于人群的妊娠体重增长图表可用于表示将早孕 BMI 考虑在内的妊娠体重增加作为与胎龄标准化的 z 评分。z 评分可用于更好地理解妊娠体重增加与母婴健康并发症之间的关系。
