Taking extra folic acid in the weeks leading up to and just following getting pregnant could reduce the risk of the child having severe language delay, according to new research from Norway.

The study tracked the use of folic acid supplements and other supplements in nearly 40,000 expectant women and their children and found that those women who took folic acid in the four weeks prior to and eight weeks after conception had children who were about half as likely to experience severe language delay at age 3. Toddlers who could only speak in one word or unintelligible utterance were rated as having severe language delay.

Folic acid, also known as folate, is a type of vitamin B found in green leafy vegetables, citrus fruits, dried beans and liver. Folic acid is an essential vitamin the body needs for proper functioning, particularly during the first few weeks of life.

Folic acid is known to be an important prenatal nutrient and has been tied to reduced birth defects and a lowered risk of premature birth when taken by expectant mother.  This study is the first to suggest that this nutrient is specifically related to severe language delay.

“If in future research this relationship were shown to be causal, it would have important implications for understanding the biological processes underlying disrupted neurodevelopment, for the prevention of neurodevelopmental disorders, and for policies of folic acid supplementation for women of reproductive age,” study author Christine Roth of the Norwegian Institute of Public Health, writes.

The study was published Tuesday in the October issue of the Journal of the American Medical Association.

In the United States, the government has required that enriched grains be fortified with folic acid for decades — a regulatory change that a 2001 study by the Centers for Disease Control and Prevention credited with reducing certain birth defects in the population by 20 percent.  Grains are not enriched with folic acid in Norway.

Fortification only goes so far, however:  Enriched foods are designed to give an average eater about 100 micrograms of folic acid per day, but experts say women need at least 400 micrograms to help protect their babies from certain birth defects.