陕西省妇女产前检查与子女出生体重关系的多水平线性模型分析
Multilevel linear model analysis of the relationship between prenatal care and neonatal birth weight in Shaanxi Province

摘要：目的 应用多水平线性模型分析陕西省妇女产前检查与子女出生体重的关系。方法 采用分层多阶段随机抽样的方法，于2013年8月-11月间以一对一问卷调查的方式，收集陕西省2010-2013年怀孕且结局明确的15～49岁育龄妇女及其子女的信息。分别以妇女产前检查次数和子女出生体重作为自变量和因变量，通过逐步校正混杂因素共建立3个多水平线性模型，其中Model 1仅分析产前检查次数变量，Model 2在Model 1的基础上进一步校正相关社会人口学特征因素，Model 3在Model 2的基础上进一步校正产次、孕期保健、生活方式及孕期健康状况等因素。 结果 与产前检查<5次组相比，产前检查≥5次组中妇女的文化程度较高，城镇居民、生育年龄在20～35岁之间、有工作的较多，家庭经济状况较好，经产妇较少，首次产检≤13周的较多，孕期服用叶酸的较多，孕期被动吸烟的较少，孕期患贫血的较多。从Model 1～Mode 3，产前检查≥5次组子女的出生体重均显著高于产前检查<5次组者(P<0.01)。Model 2与Model 1相比β估计值降低了28%。校正完所有混杂因素后，Model 3显示产前检查≥5次可以使子女的出生体重增加38.78g。结论 提高产前检查次数，及时发现并调整相关因素，可提高子女的出生体重。
ABSTRACT: Objective To explore the relationship between prenatal care (PNC) and neonatal birth weight in Shaanxi Province by using the multilevel linear model. Methods By using a stratified multi-stage sampling method, the information of 15-49 childbearing aged women who were in pregnancy or had definite pregnancy outcomes and their offspring born during 2010 and 2013 was collected through a face-to-face questionnaire survey from August to November 2013 in Shaanxi Province. A multilevel linear model was employed to investigate the association between neonatal birth weight and the number of PNC visits and to control the confounders step by step. We established three models in this study: Model 1 included the variable of PNC visits, Model 2 was adjusted for variables in Model 1 plus some other demographic characteristics, and Model 3 was adjusted for variables in Model 2 plus the pregnancy history, healthcare, lifestyle and health status during pregnancy. Results Compared with women in <5 PNC visits group, women of ≥5 PNC visits group had the following characteristics: higher educational level, higher proportion of urban residents and maternal childbearing age during 20~35, higher employment rate, better economic status, more pluripara, higher proportion of first visit ≤13 weeks, higher proportion of using folic acid, lower proportion of exposure to second-hand smoke, higher proportion of suffering from anemia during pregnancy. ≥5 PNC visits could significantly increase the mean birth weight compared with <5 PNC visits from Model 1 to Model 3 (P<0.01). The β-estimate had a 28% reduction in Model 2 compared with Model 1. After controlling for all the confounders, ≥5 PNC visits could increase the birth weight by 38.78g. Conclusion The mean birth weight can be increased by increasing the number of PNC visits, detecting and adjusting for related factors