[Effects of folic acid fortification in the rates of malformations at birth in Chile].

Background: The effects of folic acid fortification on neural tube defects is well known. Other reports show a beneficial effect of the fortification on orofacial clefts, urinary malformations and defects caused by limb reduction.

Aim: To determine the changes in prevalence of congenital malformations after the start of flour folic acid fortification in Chile.