Nov. 5 (HealthDay News) -- Canadian public health measures that spurred folic acid intake among women may have helped cut the rate of congenital heart disease in newborns, researchers report.

In 1993, Canada issued guidelines recommending folic acid supplements. Folic acid fortification of flour was recommended in 1996 and made mandatory in 1998.

In this study, a team at McGill University in Montreal identified more than 2,200 babies with severe congenital heart disease born in Quebec from 1990 to 2001. The researchers compared the incidence of such birth defects in four different folic acid-related periods: pre-supplementation; pre-fortification; transition to fortification; and post-fortification.

They found there wasn't a significant decline in the average prevalence of severe congenital heart defects in newborns until the post-fortification period (1.94 vs. 1.72 cases per 1,000 live births).

"Public health measures to increase folic acid intake were followed by a decrease in number of severe congenital heart disease births, supporting the hypothesis that folic acid may have had a preventive effect on congenital heart disease," the researchers concluded.

The study was presented Sunday at the American Heart Association annual meeting in Orlando, Fla.

SOURCE: Nov. 4, 2007, presentation, American Heart Association annual meeting, Orlando, Fla.