妇女围受孕期叶酸服用情况及其对胎儿神经管缺陷的预防效果

目的: 了解北京市妇女围受孕期服用叶酸的依从性,探索服用叶酸对胎儿神经管缺陷(neural tube defects,NTDs)的预防效果,分析影响叶酸服用依从性的因素,并提出改善叶酸服用依从性的对策和建议。方法: 以通州区2013—2018年92 121例分娩妇女的常规孕期保健数据和人群出生缺陷监测数据为基础,计算妇女的叶酸服用率和依从服用率(即孕前开始且规律服用率), 并分析服用叶酸与NTDs发生率的关系,同时采用单因素及多因素Logistic回归模型分析叶酸依从服用率的影响因素,并提出改善妇女围受孕期叶酸服用依从性的对策。结果: 6年间,妇女围受孕期叶酸总服用率为90.08%,有微弱上升趋势,而叶酸依从服用率仅为41.5%,且呈明显下降趋势。服用叶酸的妇女其胎儿NTDs的发生率是(5.5/万)未服用叶酸者(19.7/万)的27.9% (χ²=23.74,P<0.001),而服用单纯叶酸片和服用含叶酸的多种微量营养素的NTDs发病率未见统计学差异。母亲围受孕期补充叶酸可以减少70%的NTDs发病风险(RR=0.28,95%CI:0.16~0.49),且对无脑畸形和脊柱裂亚型均有预防效果。控制混杂因素后,本地户籍、文化程度为高中及以上的妇女叶酸依从服用率高于外地户籍、文化程度为初中及以下的妇女(P<0.05),年龄小于25岁、孕前偏瘦或肥胖的妇女、经产妇的叶酸依从服用率低于相应对比组(P<0.05)。结论: 北京市通州区妇女围受孕期叶酸服用率较高,但服用依从性较低,妇女围受孕期未服用叶酸严重影响NTDs的预防效果。叶酸依从服用率受妇女的年龄、文化程度、职业、户籍地、产次等多种因素影响,应重点关注年龄小于25岁、体型消瘦或肥胖、文化程度较低、经产及夫妻均为外地户籍的妇女,以提高围受孕期叶酸服用的依从性,更好地发挥叶酸预防NTDs的效果。

Maternal periconceptional folic acid supplementation and its effects on the prevalence of fetal neural tube defects

Objective: To find out the status of folic acid supplementation among women, to evaluate the prevention effects on neural tube defects (NTDs), and to explore the factors impact on folic acid supplementation compliance. Methods: Based on the routine data of 92 121 women in prenatal health care and birth defect surveillance system in Tongzhou District of Beijing from 2013 to 2018, we described the prevalence of periconceptional folic acid supplementation, pre-pregnancy folic acid supplementation and regularly folic acid supplementation (compliance supplementation). Trend χ ² tests were used to evaluate the change of folic acid supplementation prevalence. The prevalence difference among the women with folic acid supplementation and without supplementation were tested with Fisher’s exact test. Factors asso-ciated with folic acid supplementation compliance rate were analyzed with univariate and multivariate Logistic regression model. Results: The prevalence of periconceptional folic acid supplementation during the six years was 90.08% and it was increased from 2013 to 2018, but the rate of pre-pregnancy and regular supplementation was only 41.5% and declined from 2013 to 2018, especially 2013 to 2015. The prevalence of NTDs among the fetuses whose mothers took folic acid during periconceptional period was 5.5/10 000, while the prevalence for the fetuses whose mothers did not take folic acid was 19.7/10 000 (P<0.001), the rates ratio was 27.9% (χ²=23.74, P<0.001). The difference between the prevalence of NTDs among the fetuses whose mothers took folic acid only and multiple micronutrients was not statistically significant. After controlling the confounding factors, it was found that the compliant folic acid supplementation rates in women, whose household registrations were outside Beijing and whose education levels were junior high school or below, and who were younger than 25 years old, and who were multiparas and who were pre-pregnancy underweight or obese, were lower than those of the corresponding control groups (P<0.05). Conclusion: The rate of folic acid supplementation among women in Tongzhou District of Beijing was relatively high, but their compliance was poor. Women who did not take folic acid during periconception seriously affected the prevention effect of NTDs. We should focus on women who are younger than 25 years old, lower educated, pre-pregnancy underweight or obese, multiparas and nonlocal household registers, in order to improve the periconceptional folic acid supplementation compliance and improve the effects of NTDs prevention.