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Sept. 5, 2001 -- Although the role of folic acid in preventing certain birth defects is established, many women of childbearing age don't seem to be heeding the message before they conceive, a new poll suggests.
Why? Their doctors aren't routinely telling them to take a daily multivitamin -- containing 400 micrograms of folic acid -- before conception, according to a poll of more than 2,000 women aged 18 to 45. Conducted for the March of Dimes, the survey follows up four previous polls of women's knowledge and behavior regarding a healthy pregnancy.
Folic acid supplementation before conception and during the first trimester of pregnancy is known to reduce risk for neural tube birth defects. Such birth defects -- including spina bifida and anencephaly -- affect 4,000 pregnancies per year resulting in 2,500 to 3,000 U.S. births annually. Spina bifida, or open spine, occurs when the backbone never closes completely and is a leading cause of childhood paralysis. Anencephaly is marked by a severely underdeveloped brain and skull.
The new survey found that awareness of the role folic acid plays in a healthy pregnancy jumped from 52% to 79% from 1995 to 2001 but, overall, just under 30% of women of childbearing age report taking a multivitamin on a daily basis.
However, only 7% of women knew that folic acid should be taken before they become pregnant, and more than three-quarters say their doctors haven't discussed the benefits of folic acid with them. Among women who didn't take a daily multivitamin, one in five said they would be more likely to do so if their doctor recommended it.
"We want to emphasize the importance of taking a daily multivitamin before and during pregnancy," says Janis Biermann, director of the National Folic Acid Campaign at the March of Dimes in White Plains, N.Y.
Half of all pregnancies in the U.S. are unplanned, Biermann says. "The neural tube forms by 28 days, so if you are not taking 400 micrograms of folic acid on a daily basis, you wouldn't be afforded the possible prevention."
So why are doctor's keeping mum?
"Doctors have so few minutes with patients that they have to prioritize, and neural tube defects only affect one in 2,500 live births, so some physicians don't think it's the most important message and some may not be aware of the role of folic acid in prevention," Biermann says.
"The biggest point to make is that you can prevent some very devastating birth defects by taking folic acid before you get pregnant, and half of all pregnancies are unplanned, so you have to do it before," says James Mills, MD, MS, chief of the pediatric epidemiology section at the National Institute of Child Health and Human Development in Bethesda, Md. "You can't assume that you won't get pregnant before you want to."
Because many women were not taking a daily supplement containing folic acid, the FDA required in 1998 that all breads, pastas, rice, flour, cereal and other cereal grain products be fortified at the rate of 140 micrograms per 100 grams of grain. Since then, there has been a 19% drop in neural tube defects, according to a study in a recent issue of the Journal of the American Medical Association.
But "the amount that the average women gets from fortified foods is not the amount that will give her optimal protection, so a multivitamin is still necessary," Mills tells WebMD.