Bell Karen N, Oakley Godfrey P
Department of Epidemiology, Rollins School of Public Health of Emory University, Gloucester, Massachusetts, USA.
Birth Defects Res A Clin Mol Teratol. 2009 Jan;85(1):102-7. doi: 10.1002/bdra.20504.
The number of countries fortifying wheat and maize flour with folic acid has increased in the past 2 years. Folic acid prevents most cases of spina bifida and anencephaly by raising serum folate levels among women capable of bearing children, as does encouraging women to consume folic acid supplements prior to pregnancy.
The progress in preventing these serious birth defects can be measured by tracking the number of countries now fortifying and program coverage in each. Country estimates of the number of pregnancies affected by spina bifida and anencephaly are calculated using a prefortification birth prevalence baseline and estimates of the proportion prevented by wheat and maize flour fortified with folic acid.
Current fortification programs are preventing about 22,000, or 9% of the estimated folic acid-preventable spina bifida and anencephaly cases. This represents an annual global decrease of about 6,600 folic acid-preventable spina bifida and anencephaly cases since 2006.
The pace of preventing these serious birth defects can be accelerated if more countries require fortification of both wheat and maize flour and if regulators set fortification levels high enough to increase a woman's daily average consumption of folic acid to 400 mcg.
在过去两年中，强化小麦粉和玉米粉中添加叶酸的国家数量有所增加。叶酸通过提高育龄妇女的血清叶酸水平来预防大多数脊柱裂和无脑儿病例，鼓励妇女在怀孕前服用叶酸补充剂也有同样的效果。
预防这些严重出生缺陷的进展可以通过跟踪目前进行强化的国家数量以及每个国家的项目覆盖范围来衡量。使用强化前的出生患病率基线以及添加叶酸的小麦粉和玉米粉预防的比例估算值，来计算受脊柱裂和无脑儿影响的怀孕数。
目前的强化项目预防了约22,000例，即估计可通过叶酸预防的脊柱裂和无脑儿病例的9%。这意味着自2006年以来，全球每年可通过叶酸预防的脊柱裂和无脑儿病例减少约6,600例。
如果更多国家要求对小麦粉和玉米粉都进行强化，并且监管机构将强化水平设定得足够高，以使女性每日叶酸平均摄入量增加到400微克，那么预防这些严重出生缺陷的速度将会加快。
