Department of Obstetrics and Gynaecology, Faculty of Medicine, University of British Columbia, Vancouver, Canada.
Department of Epidemiology, School of Public Health, University of Pittsburgh, Pittsburgh, USA.
Br J Nutr. 2024 Sep 28;132(6):751-761. doi: 10.1017/S0007114524001855. Epub 2024 Oct 2.
Pregnancy weight gain standards are charts describing percentiles of weight gain among participants with no risk factors that could adversely affect weight gain. This detailed information is burdensome to collect. We investigated the extent to which exclusion of various pre-pregnancy, pregnancy and postpartum factors impacted the values of pregnancy weight gain percentiles. We examined pregnancy weight gain (kg) among 3178 participants of the US nuMoM2b-Heart Health Study (HHS). We identified five groups of potential exclusion criteria for pregnancy weight gain standards: socio-economic characteristics (group 1), maternal morbidities (group 2), lifestyle/behaviour factors (group 3), adverse neonatal outcomes (group 4) and longer-term adverse outcomes (group 5). We established the impact of different exclusion criteria by comparing the median, 25th and 75th percentiles of weight gain in the full cohort with the values after applying each of the five exclusion criteria groups. Differences > 0·75 kg were considered meaningful. Excluding participants with group 1, 2, 3 or 4 exclusion criteria had no impact on the 25th, median or 75th percentiles of pregnancy weight gain. Percentiles were only meaningfully different after excluding participants in group 5 (longer-term adverse outcomes), which shifted the upper end of the weight gain distribution to lower values (e.g. 75th percentile decreased from 19·6 kg to 17·8 kg). This shift was due to exclusion of participants with excess postpartum weight retention > 5 kg or > 10 kg. Except for excess postpartum weight retention, most potential exclusion criteria for pregnancy weight gain standards did not meaningfully impact chart percentiles.
妊娠增重标准是描述无不良因素影响增重的参与者体重增加百分位数的图表。这些详细信息收集起来很繁琐。我们研究了排除各种孕前、孕期和产后因素对妊娠增重百分位数值的影响程度。我们分析了美国 nuMoM2b-心脏健康研究（HHS）3178 名参与者的妊娠增重（kg）。我们确定了妊娠增重标准的五类潜在排除标准：社会经济特征（第 1 组）、孕产妇合并症（第 2 组）、生活方式/行为因素（第 3 组）、不良新生儿结局（第 4 组）和长期不良结局（第 5 组）。我们通过比较全队列中体重增加的中位数、第 25 百分位数和第 75 百分位数与应用五类排除标准组后各值之间的差异，确定了不同排除标准的影响。差异>0.75kg 被认为具有重要意义。排除具有第 1、2、3 或 4 组排除标准的参与者对妊娠增重的第 25、中位数或第 75 百分位数没有影响。仅在排除第 5 组（长期不良结局）参与者后，百分位数才有明显差异，这将增重分布的上限转移到较低的值（例如，第 75 百分位数从 19.6kg 降至 17.8kg）。这种转变是由于排除了产后体重滞留超过 5kg 或超过 10kg 的参与者。除了产后体重滞留过多外，妊娠增重标准的大多数潜在排除标准对图表百分位数没有明显影响。
