Protein intake and weight gain among low-income pregnant women from Mesquita County, Rio de Janeiro, Brazil

ABSTRACT Objective To evaluate the effect of protein intake on body weight gain at pregnancy. Methods A cross-sectional study was carried out with 297 women who delivered a child at the maternity ward of Municipal Hospital Leonel de Moura Brizola in Mesquita city in the state of Rio de Janeiro. Sociodemographic and anthropometric data were collected through the use of a structured questionnaire at first week after delivery. Food intake was assessed by a food frequency questionnaire. Protein intake per kilogram of body weight (g/kg per day) during pregnancy was categorized as high or low protein intake according to overall median levels. Hierarchical multiple linear regression was fitted to estimate the effect of protein intake per kg during pregnancy on weight gain. Results Women presented an average weight gain of 12.8kg (SD=6.34) and 26.8kg/m2 (SD=4.78) of Body Mass Index. Those who consumed a diet with high levels of protein content significantly presented less weight at postpartum (p<0.01) lower Early-Pregnancy Body Mass Index (p<0.01). In the hierarchical linear regression, it was found a negative association of protein intake per kg and Weight gain (b=-4.3025; IC95%=-6.0215; -2.5836; p<0.01). In the final model, all others covariates (energy, schooling, family income and gestational age) were significantly associated with the outcome (p<0.05). The additional model showed a negatively association between Early-Pregnancy Body Mass Index and weight gain (b=-0.2951; IC95%= -0.4987; -0.0915; p<0.01). Conclusion Higher levels of protein intake per kg of body weight during pregnancy were associated with lower weight gain.

摘要 研究目的：旨在探讨妊娠期蛋白质摄入量对产妇体质量增长的影响。方法：本研究采用横断面设计，纳入里约热内卢州梅斯基塔市Leonel de Moura Brizola市立医院产科的297名分娩女性。于分娩后第一周采用结构化问卷收集研究对象的社会人口学及人体测量学数据；通过食物频率问卷评估其膳食摄入情况。根据总体中位数水平，将妊娠期每千克体质量的蛋白质摄入量（g/kg·d）划分为高、低蛋白质摄入组。采用分层多重线性回归模型，评估妊娠期每千克体质量蛋白质摄入量对体质量增长的影响。结果：研究对象的平均体质量增长为12.8kg（标准差SD=6.34），孕早期体质指数（Body Mass Index, BMI）均值为26.8kg/m²（SD=4.78）。高蛋白摄入组产妇的产后体质量及孕早期体质指数均显著更低（均p<0.01）。分层线性回归分析结果显示，每千克体质量蛋白质摄入量与体质量增长呈负相关（b=-4.3025；95%置信区间：-6.0215~-2.5836；p<0.01）。最终模型中，其余所有协变量（能量摄入、受教育程度、家庭收入及孕周）均与研究结局呈显著关联（p<0.05）。补充模型分析显示，孕早期体质指数与体质量增长呈负相关（b=-0.2951；95%置信区间：-0.4987~-0.0915；p<0.01）。结论：妊娠期每千克体质量的蛋白质摄入量越高，产妇体质量增长越低。