WASHINGTON, Jan. 25 (Xinhua) -- A new study shows women who are pregnant or planning to become pregnant have bigger risk of having babies with neural tube birth defects as they avoid diets that reduce or eliminate carbohydrates.

The study, published Thursday in the journal Birth Defects Research, found that women with low carbohydrate intake are 30 percent more likely to have babies with neural tube defects, such as malformations of the spine and spinal cord and the absence of major portions of the brain and skull, when compared with women who do not restrict their carbohydrate intake.

This is the first study to evaluate the relationship between low carbohydrate intake and having children with neural tube defects.

Neural tube defects are major birth defects of the brain and spine that occur early in pregnancy due to improper closure of the embryonic neural tube.

"This is concerning because low carbohydrate diets are fairly popular," said Tania Desrosiers, research assistant professor of epidemiology at the University of North Carolina at Chapel Hill, who led the study.

Folic acid is an essential nutrient that minimizes the risk of neural tube defects. Desrosiers and her study collaborators found that the dietary intake of folic acid among women with restricted carbohydrate intake was less than half of other women.