Vitamin B2 (Riboflavin)
Pregnant women can obtain all the riboflavin they need during pregnancy through a varied diet. It is documented that vegans and vegetarians are more at risk of deficiency, but eating fortified grains or cereals can make up for a lack of riboflavin consumption in meat and/or dairy products.
There is some research regarding birth outcomes of infants exposed to either supplementation or deficiency of riboflavin, as well as the effect of riboflavin on preeclampsia during pregnancy, but conclusions are inconsistent and research remains ongoing.
However, riboflavin is not a common concern during pregnancy as deficiency is very rare and supplementation is therefore not recommended.
Background
Riboflavin assists in energy production and cellular function, growth and development, and the metabolism of fats, drugs, and steroids in adults (similar to thiamin).
Pregnancy
Evidence regarding risks of birth defects or other potential fetal health problems from riboflavin deficiency have been inconsistent (however, deficiency is very rare).
More specifically, there is conflicting evidence whether riboflavin deficiency is associated with a higher risk of preeclampsia in the mother.
A study of 154 pregnant women at increased risk of preeclampsia found that those who were riboflavin deficient were 4.7 times more likely to develop preeclampsia than those who were not deficient.
However, a second study of 450 pregnant women at high risk for preeclampsia found that supplementation with 15 mg of riboflavin daily did not prevent preeclampsia.
Regardless, infants of riboflavin-deficient mothers tend to be deficient themselves at birth, so ensuring adequate supply of riboflavin may be necessary for women at risk (such as those who do not eat meat or dairy products).
However, riboflavin deficiency is extremely rare in the United States, and the exact point at which deficiency occurs is not known, as it generally occurs with deficiencies of other water-soluble vitamins.
It is recommended pregnant women receive 1.4 milligrams (mg) of riboflavin daily. Consuming a varied diet should supply 1.5 mg to 2 mg of riboflavin/day. Intakes of riboflavin from food that are many times this recommendation does not appear to be toxic, possibly because any excess is either not absorbed or eliminated through urine.
Food Sources
Foods that are particularly rich in riboflavin include eggs, organ meats (kidneys and liver), chicken, fish, nuts, green vegetables, grains, fortified cereals, and milk.
A significant amount of riboflavin is lost in boiled cooking water because it is water-soluble. Heat – such as steaming and microwaving – also breaks it down.
Action
Women who are concerned about their nutrition during their pregnancy need to talk to their health care provider (HCP). Riboflavin deficiency is rare, but an overall discussion with an HCP about a woman's nutrition may help HCPs assess a woman's diet for potential improvements during pregnancy.
Resources
Riboflavin (Health Encyclopedia; University of Rochester)