De Wals Philippe, Rusen Ira David, Lee Nora S, Morin Pascale, Niyonsenga Théophile
Département de Médecine Sociale et Préventive, Université Laval, Québec, Canada.
Birth Defects Res A Clin Mol Teratol. 2003 Nov;67(11):919-23. doi: 10.1002/bdra.10124.
In Canada, the first recommendations on the use of folic acid (FA) supplements by women planning a pregnancy or capable of becoming pregnant were issued in 1993. In 1998, fortification of flour with FA became mandatory. The objective of this study was to assess the impact of these measures on the prevalence of neural tube defects (NTDs) in the province of Quebec.
The study population included stillbirths, live births, and elective terminations for fetal malformations that were reported in 1992-2000 for women residing in the province of Quebec. NTD cases were identified from stillbirth certificates and hospital discharge summaries.
There was a marked decrease in the total NTD rate after 1997. The average NTD rate was 1.89 per 1000 total births during the period of 1992-1997, and 1.28 per 1000 in 1998-2000, a 32% reduction (p < 0.001).
Fortification of flour, which began in early 1997 and gradually became widespread, is a very plausible explanation for the timing, shape, and magnitude of the decrease in NTD prevalence observed in Quebec and other Canadian provinces. An increase in FA supplement use may have played only a minor role. Birth Defects Research (Part A) 67:000-000, 2003.
在加拿大，1993年发布了关于计划怀孕或可能怀孕的女性使用叶酸（FA）补充剂的首批建议。1998年，强制要求在面粉中添加叶酸。本研究的目的是评估这些措施对魁北克省神经管缺陷（NTD）患病率的影响。
研究人群包括1992 - 2000年期间居住在魁北克省的死产、活产以及因胎儿畸形而进行的选择性引产。通过死产证明和医院出院小结来确定NTD病例。
1997年后，NTD总发生率显著下降。1992 - 1997年期间，每1000例总出生数中NTD平均发生率为1.89，1998 - 2000年为1.28，下降了32%（p < 0.001）。
始于1997年初并逐渐普及的面粉强化，是魁北克省和加拿大其他省份NTD患病率下降的时间、形式和幅度的一个非常合理的解释。叶酸补充剂使用的增加可能仅起了较小的作用。《出生缺陷研究》（A部分）67:000 - 000，2003年。
