Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California, Berkeley, California, United states of America.
Department of Epidemiology, Biostatistics and Occupational Health, McGill University Faculty of Medicine, Montréal, Québec, Canada.
PLoS One. 2019 Sep 25;14(9):e0222888. doi: 10.1371/journal.pone.0222888. eCollection 2019.
Seasonality of food availability, physical activity, and infections commonly occurs within rural communities in low and middle-income countries with distinct rainy seasons. To better understand the implications of these regularly occurring environmental stressors for maternal and child health, this study examined seasonal variation in nutrition and health care access of pregnant women and infants in rural South Africa.
We analyzed data from the Venda Health Examination of Mothers, Babies and their Environment (VHEMBE) birth cohort study of 752 mother-infant pairs recruited at delivery from August 2012 to December 2013 in the Vhembe District of Limpopo Province, the northernmost region of South Africa. We used truncated Fourier series regression to assess seasonality of antenatal care (ANC) attendance, dietary intake, and birth size. We additionally regressed ANC attendance on daily rainfall values. Models included adjustment for sociodemographic characteristics.
Maternal ANC attendance, dietary composition, and infant birth size exhibited significant seasonal variation in both unadjusted and adjusted analyses. Adequate frequency of ANC attendance during pregnancy (≥ 4 visits) was highest among women delivering during the gardening season and lowest during the lean (rainy) season. High rainfall during the third trimester was also negatively associated with adequate ANC attendance (adjusted OR = 0.59, 95% CI: 0.40, 0.86). Carbohydrate intake declined during the harvest season and increased during the vegetable gardening and lean seasons, while fat intake followed the opposite trend. Infant birth weight, length, and head circumference z-scores peaked following the gardening season and were lowest after the harvest season. Maternal protein intake and ANC ≤ 12 weeks did not significantly vary by season or rainfall.
Seasonal patterns were apparent in ANC utilization, dietary intake, and fetal growth in rural South Africa. Interventions to promote maternal and child health in similar settings should consider seasonal factors.
在食物供应、体力活动和感染方面具有明显雨季的中低收入国家的农村社区中，通常会出现季节性变化。为了更好地了解这些经常出现的环境压力因素对孕产妇和儿童健康的影响，本研究检查了南非农村地区孕妇和婴儿营养和医疗保健获取的季节性变化。
我们分析了 2012 年 8 月至 2013 年 12 月在南非林波波省北部 Vhembe 区从分娩时招募的 752 对母婴进行的 Venda 母婴及其环境健康检查（VHEMBE）出生队列研究的数据。我们使用截断傅里叶级数回归来评估产前护理（ANC）就诊、饮食摄入和出生体重的季节性。我们还将 ANC 就诊情况回归到每日降雨量值。模型包括对社会人口统计学特征的调整。
在未经调整和调整分析中，产妇 ANC 就诊、饮食成分和婴儿出生体重均表现出显著的季节性变化。怀孕期间 ANC 就诊频率足够（≥4 次）的妇女在园艺季节最高，而在贫瘠（雨季）季节最低。第三孕期高降雨量也与足够的 ANC 就诊呈负相关（调整后的 OR=0.59，95%CI：0.40，0.86）。碳水化合物摄入量在收获季节下降，在蔬菜园艺和贫瘠季节增加，而脂肪摄入量则相反。婴儿出生体重、长度和头围 z 分数在园艺季后达到峰值，在收获季后最低。蛋白质摄入量和 ANC≤12 周的产妇在季节或降雨量方面没有显著差异。
在南非农村地区，ANC 利用率、饮食摄入和胎儿生长均出现季节性模式。在类似环境中促进母婴健康的干预措施应考虑季节性因素。
