围孕期叶酸摄入与早产不同亚型的相关性研究

Study on correlation between folic acid supplementation during perigestational period and different subtypes of preterm birth

目的探讨孕前、孕期摄入叶酸补充剂的持续时间与早产不同亚型的相关性。方法建立出生队列研究,收集2010至2012年在甘肃省某妇幼专科医院建卡定期产检并随访到正常分娩的10 542例孕妇,最终以纳入的10 179例孕妇为研究对象,用病例对照研究方法分析孕前、孕期摄入叶酸补充剂的持续时间与不同亚型早产的相关性。结果以孕前、孕期均未服用叶酸补充剂的研究对象作为对照,在调整母亲年龄等混杂因素后,发现服用叶酸补充剂持续时间>12周可降低早产的发生风险(OR=0.72,95%CI:0.58~0.89,P=0.020),并具有显著的剂量反应关系,特别是降低了自发性早产的发生风险(OR=0.69,95%CI:0.54~0.88,P=0.000);同时发现长期持续地服用叶酸补充剂可降低早期早产的发生风险(OR=0.54,95%CI:0.34~0.85,P=0.000)。结论在孕前至孕期连续叶酸补充剂的摄入可降低早产发生的风险,而且保护效果因不同早产亚型而异,建议孕前及孕期可长期适量服用叶酸补充剂。

Objective To investigate relationship between duration of folic acid supplementation in perigestational periods and different subtypes of preterm birth.Methods A birth cohort study was conducted.A total of 10 542 pregnant women who underwent regular prenatal examination and were followed up to normal childbirth were collected,including 10 179 pregnant women with live singleton births as the study subjects in a specialist hospital for maternity and child health in Gansu province in a period from year 2010 to 2012.In case control study method,the correlation between duration of folic acid supplementation in pregestational period and gestational period and different subtypes of preterm birth was analyzed.Results The pregnant women who hadn’t taken folic acid supplements during either pregestational period or gestational period were divided into control group and the pregnant women who had taken folic acid supplement were divided into folic acid supplementation group.After adjusting some confounding factors such as maternal age,family monthly per capita income,maternal work in gestational period,maternal educational degree,pregestational maternal BMI,maternal body weight increment during gestational period,parity,no suffering from preeclampsia,no suffering from gestational diabetes mellitus(GDM),no having preterm labor history and no having cesarean section history,it was found that the duration of folic acid supplementation more than 12 weeks reduced risk of preterm labor(OR=0.72,95%CI:0.58~0.89) with a significant dose-response relationship(P=0.02),especially for spontaneous preterm labor(OR=0.69,95%CI:0.54~0.88)(P=0.000).Furthermore,long-term continuous folic acid supplementation reduced risk of very preterm labor(OR=0.54,95%CI:0.34~0.85)(P=0.000).Conclusion Continuous folic acid supplementation in pregestational period up to gestational period for more than 12 weeks reduces the risk of preterm labor,and this protective effect varies by preterm subtypes,so,it is recommended that the pregnant women should take folic acid supplements for a long time during their pregestational period and gestational period.