Abstract for presentation at 11th International Congress of Human Genetics

Background: In Chile, starting January 2000, the Chilean Ministry of Health mandated the addition of folic acid (FA) to wheat flour to reduce the risk of NTD. This policy resulted in a mean additional consumption of FA of 427ug/d and significant increases in serum and red cell folate in women of fertile age.
Objective: to investigate the effect of this intervention on the incidence of NTD and on multiple birth and stillbirth rates in Santiago,Chile.
Methods: In a prospective hospital-based design, the frequency of NTD was studied in all births,live births and stillbirths with BW > 500 g in the 9 public maternity hospitals of Santiago, Chile during 1999-2000 (pre-fortification period) and 2001-2004 (post-fortification period).The registry of multiple births included all pregnancies with two or more fetuses (live births and stillbirths.
Results: During the pre-fortification period there were a total of 120,566 births and the NTD rate was 17.1/10,000 births. During the post-fortification period there were a total of 227,080 births and the NTD rate was significantly reduced by 48 % to 8.9/10,000 births. Rates of anencephaly, encephalocele and spina bifida were 6.0, 2.4, and 8.7/10,000 respectively in the pre-fortification period and 2.8, 1.8, and 4.3/10,000 births respectively in the post-fortification period. This implies reductions of 53.3% in anencephaly, 25% in encephalocele and 50.6% in spina bifida. During the evaluated period there were no significant changes in the rate of multiple births. A significant reduction of 21,5% in the stillbirth rate was observed.
Conclusions: In Chile, the fortification of wheat flour with FA has proven to be an effective and cost-saving strategy for the primary prevention of NTD in a dramatically short period of time. The intervention was associated with a decrease in the stillbirth rate, and had no effect on the rate of multiple births.