Cordero Amy M, Crider Krista S, Rogers Lisa M, Cannon Michael J, Berry R J
MMWR Morb Mortal Wkly Rep. 2015 Apr 24;64(15):421-3.
Neural tube defects (NTDs) such as spina bifida, anencephaly, and encephalocele are serious birth defects of the brain and spine that occur during the first month of pregnancy when the neural tube fails to close completely. Randomized controlled trials and observational studies have shown that adequate daily consumption of folic acid before and during early pregnancy considerably reduces the risk for NTDs. The U.S. Public Health Service recommends that women capable of becoming pregnant consume 400 µg of folic acid daily for NTD prevention. Furthermore, fortification of staple foods (e.g., wheat flour) with folic acid has decreased folate-sensitive NTD prevalence in multiple settings and is a highly cost-effective intervention.
神经管缺陷（NTDs），如脊柱裂、无脑儿和脑膨出，是严重的脑和脊柱出生缺陷，发生在怀孕的第一个月，此时神经管未能完全闭合。随机对照试验和观察性研究表明，在怀孕早期及之前每天摄入足够的叶酸可显著降低患神经管缺陷的风险。美国公共卫生服务部建议，有怀孕能力的女性每天摄入400微克叶酸以预防神经管缺陷。此外，在多种情况下，用叶酸强化主食（如小麦粉）已降低了对叶酸敏感的神经管缺陷的患病率，这是一种极具成本效益的干预措施。
