As many as half of certain birth defects could be prevented if women of childbearing age consumed more folic acid, says a panel of experts as they release new guidelines about the vitamin.
It's long been known that folic acid supplements can help prevent neural tube defects, such as spina bifida. All Canadian women of child-bearing age have been advised to take a multivitamin containing 0.4 mg of folic acid every day.
But now the experts from the Society of Obstetricians and Gynaecologists of Canada and the Motherisk program at Toronto's Hospital for Sick Children are calling on women to step up those levels.
They say women planning pregnancy should take a multivitamin containing between 0.4 and 1.0 milligram of folic acid at least two to three months before conception, throughout pregnancy and keep taking it as long as breastfeeding continues.
What's more, women who are smokers, obese, diabetic or with a previous history of spina bifida in the family should be taking a multivitamin containing 5.0 milligrams of folic acid, three months prior to and up to 12 weeks following conception.
The panel of experts says new research suggests that folic acid can do more than cut the risk of neural birth defects; it can also reduce the rates of other birth defects such as congenital heart disease and some early pediatric cancers.
SOGC Associate Executive Vice-President Dr. Vyta Senikas says it's important that even women not planning a pregnancy but who are sexually active follow these recommendations, since about half of all pregnancies are unplanned.
"For many women, by the time they know they are pregnant, it's simply too late to reap the full protective benefit of folic acid and multi-vitamin supplements, so we need to get this information out there," Senikas says.
Because of the awareness programs about folic acid supplementation, the rates of neural tube defects has dropped in Canada, from a rate of 10 per 10,000 live births in 1991, to 5.8 per 10,000 total births (live births and stillbirths) in 1999.
Despite this progress, Dr. Senikas says many more of these birth defects could be easily prevented. The panel of experts estimates that as many as half of all birth defects could be prevented if women of childbearing age consumed an adequate more folic acid.
Folic acid works by helping to produce and maintain new cells, and is important during the early growth of an embryo, when rapid cell division and growth are occurring.
Since 1998, there has been mandatory folic acid fortification of white flour, enriched pasta, and cornmeal in Canada. The experts say that may not be enough and they would like to see the federal government increase the fortification of flour with folic acid to 300 mg/100 g from the current level of 140 mg/100 g.
A spokeswoman for the Public Health Agency of Canada says it not been formally approached about increasing folic acid fortification.
