中国妇女妊娠前后单纯服用叶酸对神经管畸形的预防效果

Preventing neural tube defects with periconceptional folic acid supplementation: a population based intervention program in the China

目的 评价妇女在妊娠前后服用单纯 40 0 μg叶酸增补剂对胎 /婴儿神经管畸形 (NTDs)的预防效果。方法 1993～ 1995年在中国北方的NTDs高发地区和南方的NTDs低发地区妇女增补叶酸的推广项目中 ,共募集从孕前或孕后任何时间开始服药的妇女 130 142名 ,未服药的妇女 1176 89名 ;设计的服药方法从婚检时开始到孕满 3个月为止 ,每天服用单纯叶酸片 40 0 μg ;最后对妇女的分娩结局进行监测并进行预防效果的对比评价研究。结果 服药组妇女生育的胎婴儿中共发现 10 2例NTDs ,对照组胎婴儿中共发现 173例NTDs。末次月经前募集的未服药妇女在孕 2 0周以后分娩的胎婴中NTDs发生率 ,北方为 4 8‰ (16 / 3 318) ,南方为 1 0‰ (2 8/ 2 82 6 5 ) ,而妊娠前后服药妇女组则分别为1 0‰ (13/ 13 0 12 )和 0 6‰ (34/ 5 86 38)。与末次月经前募集的未服药妇女组相比 ,北方服药妇女NTDs发生率明显降低 ,其中依从性大于 80 %的服药组妇女预防率达 85 % (95 %CI为 6 2 %～ 94% ) ,南方地区服叶酸的预防率为 41% (95 %CI为 3 %～ 6 4% )。结论 妇女在妊娠前后每天服用单纯叶酸 40 0

Objectives To evaluate the effectiveness of periconceptional use of 400 μg folic acid only on the prevention of neural tube defects (NTDs). Method As part of a public health campaign in areas of high (North) and low (South) NTDs prevalence in the China during 1993 and 1995, 130 142 pill takers and 117 689 non pill takers were recruited. Women were asked to begin taking a pill containing only 400 μg of folic acid daily from the time of their premarital examination until the end of the first trimester of pregnancy. The outcomes of these pregnancies were ascertained through 1996. Results We identified 102 NTDs among offspring of pill takers and 173 NTDs among offspring of non pill takers. The NTDs rate in offspring of non pill takers was 4.8‰ (16/ 3 318) and 1.0‰ (28/28 625) in the south; while the rate in pill takers was 1.0‰ (13/13 012) in the north and 0.6‰ in the south. The greatest reduction in risk occurred among the fetuses or infants of a subgroup of women in the northern region with periconceptional use who took pills more than 80 percent of the time (reduction in risk, 85 percent as compared with the fetuses or infants of women who registered before their last menstrual period and who took no folic acid; 95 percent confidence interval, 62 to 94 percent). In the southern region the reduction in risk among the fetuses or infants of women with periconceptional use of folic acid was also significant (reduction in risk, 41 percent; 95% confidence interval, 3 to 64 percent). Conclusion Periconceptional intake of supplements containing only 400 μg folic acid can reduce the risk for NTDs in areas of high and low NTDs prevalence.