According to a new Norwegian study, women who took folic acid supplements in the first two months of pregnancy were less likely to have kids with severe language delays.
At present folic acid is known to reduce the risk of certain types of birth defects, and both the U.S. and Canada fortify grain products with folic acid to make sure pregnant women get enough of it. But that's not the case in some other countries, including Norway. Women are encouraged to take folic acid, a B vitamin found in vegetables, fruits and whole grains, before they become pregnant and throughout their pregnancy to help a fetus’s neural tube develop properly into the spinal cord and brain
This study is the first to show that using folic acid as advised can reduce a child’s severe language delays, lead study author Christine Roth said. “We don't think people should change their behavior based on these findings,” said Dr. Ezra Susser from Columbia University's Mailman School of Public Health in New York, who worked on the study. “But it does add weight to the public health recommendation to take folic acid early in pregnancy,” he said. And, he added, it shows that “what you do during pregnancy... is not only important for birth but also for subsequent development.”
For the study the researchers gave surveys to close to 40,000 Norwegian women a few months into their pregnancies. Those included questions on what supplements women were taking in the four weeks before they got pregnant through eight weeks after conception. Then, when their kids were three years old, Susser and his colleagues asked the same women about kids' language skills, including how many words they could string together in a phrase.
Toddlers who could only say one word at a time or who had “unintelligible utterances” were considered to have severe language delay. Of the 38,954 children in the study, 204 had severe language delays, defined as speaking in one-word utterances or unintelligibly at age 3. Of those, 103 were born to mothers who didn’t take folic acid or took supplements without folic acid and 101 were children of mothers who took folic acid alone or in combination with other supplements.
The pattern remained after Susser's team took into account other factors that were linked to both folic acid supplementation and language skills, such as a the mother’s weight and education, and whether or not she was married.
The researchers didn't find any link between folic acid during pregnancy and the children’s motor skills, measured by how well toddlers could kick or catch a ball.
Authors add in the Journal of the American Medical Association that this study can't prove that folic acid, itself, prevents language delay. But Susser said the vitamin is known to affect the growth of neurons and could influence how proteins are made from certain genes.
“Clearly it plays a role in development that starts very early in pregnancy,” said Usha Ramakrishnan, a maternal and child nutrition researcher from Emory University in Atlanta who wasn't involved in the new study. However, she added, it's hard to separate out exactly when during pregnancy folic acid supplements would have an effect on later language development - since women who are taking supplements early are more likely to take them throughout pregnancy.
“The reduced risk of severe language delay was associated with folic acid supplement use in the early period around conception, in very much the same period for when women should use a folic acid supplement to prevent neural tube defects,” Roth, a doctoral student in the Division of Mental Health at the Norwegian Institute of Public Health in Oslo, said. “So women should follow the public health advice of starting to take a folic acid supplement before they become pregnant.”
“The recommendation worldwide is that women should be on folate supplements through all their reproductive years,” Susser said. Because of that, “we really need to know what the impact is on children, both benefits and risks.”
“I think this adds to what's already known about the benefits of folic acid…It gives one more positive message of potential benefit,” Ramakrishnan said.
More studies are needed to determine how folic acid prevents language difficulties. The researchers plan to follow up with the children in the study when they are 5 years old.
Of the 38,954 children in the study, 204 had severe language delays, defined as speaking in one-word utterances or unintelligibly at age 3. Of those, 103 were born to mothers who didn’t take folic acid or took supplements without folic acid and 101 were children of mothers who took folic acid alone or in combination with other supplements.
The study showed that the children of mothers who took folic acid before conception and in early pregnancy had a 45 percent lower risk of the language disability.
No reduced risk of severe language delay was seen in the children of mothers who started taking folic acid supplements after the eighth week of pregnancy, Roth said. However, she cautioned that was a small group of women.
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