Veile Amanda, Kramer Karen L
Department of Anthropology, Center on Aging and the Life Course, Purdue University, West Lafayette, Indiana, 47907-2050.
Department of Anthropology, University of Utah, Salt Lake City, Utah, 84112.
Am J Hum Biol. 2017 Mar;29(2). doi: 10.1002/ajhb.22920. Epub 2016 Oct 4.
The epidemiologic link between cesarean birth and childhood obesity is unresolved, partly because most studies come from industrialized settings where many post-birth factors affect the risk for obesity. We take advantage of an unusual ethnographic situation where hospital and cesarean birth modes have recently been introduced among Yucatec Maya subsistence farmers, but young children have had minimal exposure to the nutritional transition. While we expect to find very low rates of childhood obesity, we predict that cesarean-born children will be larger and heavier than vaginally born children.
Weight and height were collected monthly on 108 children aged 0-5 (3576 observations total). Birth mode and birthweight were collected by maternal interview. Data were analyzed using linear mixed models that compare child growth [Maya population-specific Z-scores for weight-for-age and body mass index-for-age (WAZ and BMIZ)] in cesarean and vaginally born children aged 0-5 years.
The cesarean rate was 20%, no children were obese, and 5% were overweight. Cesarean birth was a significant predictor of child WAZ and BMIZ after accounting for maternal effects, child birthweight, and sex. Children who were born by cesarean to mothers with high BMI had the highest WAZ of all children by 5 years of age, and the highest BMIZ of all children at all ages.
Cesarean-born Maya children had higher BMI than vaginally born children, even in the absence of many known confounding factors that contribute to childhood obesity. Child growth was most sensitive to birth mode when mothers had high BMI.
剖宫产与儿童肥胖之间的流行病学联系尚无定论，部分原因是大多数研究来自工业化环境，在这些环境中，许多出生后的因素会影响肥胖风险。我们利用了一种特殊的人种学情况，即医院和剖宫产分娩方式最近才在尤卡坦玛雅自给自足农民中引入，但幼儿很少接触营养转型。虽然我们预计儿童肥胖率会非常低，但我们预测剖宫产出生的儿童会比阴道分娩的儿童体型更大、体重更重。
每月收集108名0至5岁儿童的体重和身高（共3576次观察）。通过产妇访谈收集分娩方式和出生体重。使用线性混合模型分析数据，该模型比较0至5岁剖宫产和阴道分娩儿童的生长情况[玛雅人群特定的年龄别体重和年龄别体重指数（WAZ和BMIZ）Z评分]。
剖宫产率为20%，没有儿童肥胖，5%超重。在考虑产妇影响、儿童出生体重和性别后，剖宫产是儿童WAZ和BMIZ的显著预测因素。剖宫产出生于高BMI母亲的儿童在5岁时WAZ最高，在各年龄段中BMIZ最高。
即使没有许多导致儿童肥胖的已知混杂因素，剖宫产出生的玛雅儿童的BMI也高于阴道分娩的儿童。当母亲BMI较高时，儿童生长对分娩方式最为敏感。
