An expectant mother wants nothing but the best for her child.
That’s often why she takes prenatal vitamins.
The supplements are often sold and marketed as necessities for proper fetal development.
However, these vitamins don’t have enough research behind them to warrant their use, according to a review of available evidence published in the Drug and Therapeutics Bulletin (DTB).
While many of the vitamins have no noted benefits, researchers say there is good cause for pregnant women to supplement their diets with folic acid and vitamin D.
Most multivitamins, researchers say, are merely an added cost without a documented return on investment.
“We found no evidence to recommend that all pregnant women should take prenatal multi-nutrient supplements beyond the nationally advised folic acid and vitamin D supplements, generic versions of which can be purchased relatively inexpensively,” researchers concluded.
The evidence behind prenatal vitamins
Some over-the-counter vitamins marketed toward pregnant women contain 20 or more vitamins or minerals.
Too see if these vitamins had the necessary science to back up their use, researchers with the DTB scoured published materials to determine the effectiveness of their claims.
Folic acid — the gold standard of prenatal vitamins — made the cut. Along with vitamin D, it’s the only supplement the DTB recommends for all pregnant women.
Folic acid, a synthetic version of folate, helps prevent neural tube defects (NTDs), such as spina bifida and anencephaly, or a birth defect where a child is born without parts of the brain or skull.
Folic acid’s protective benefits against these conditions were first identified in the 1980s, and its effectiveness has held up in scientific literature.
According to DTB researchers and the U.S. Centers for Disease Control and Prevention (CDC), half of all pregnancies are unplanned, so women of childbearing age should take 0.4 milligrams of folic acid daily.
Women at higher risk of having a child with NTDs may benefit from taking up to 5 milligrams of folic acid a day while pregnant, researchers say.
Vitamin D plays an important part in bone development, as it increases calcium consumption from the gut.
Studies show, just like folic acid, that supplementing your diet with vitamin D while pregnant translates to better health.
Women in the United Kingdom are advised to take .01 milligrams of vitamin D daily throughout pregnancy and breastfeeding.
The DTB, a publication of the British Medical Journal, notes that the United Kingdom isn’t known for having a lot of sunshine, and the dark winter months make it difficult to get adequate vitamin D from the sun.
What pregnant women don’t need
Iron is often another suggested supplement for pregnant women who sometimes experience anemia when the body doesn’t have enough red blood cells.
Iron can help this condition, but not all women need it. Iron supplementation can also cause stomach irritation, constipation, or diarrhea.
Other vitamins contained in multivitamin supplements like vitamins A, C, and E, lack evidence to suggest their effectiveness in helping mother or child.
This isn’t to say that some women may benefit from these vitamins, but there isn’t enough research to suggest all pregnant women need to take them.
“For most women who are planning to become pregnant or who are pregnant, complex multivitamin and mineral preparations promoted for use during pregnancy are unlikely to be needed and are an unnecessary expense,” the DTB paper concludes.
While women in developing countries may lack these important nutrients in their diets, women in countries like the United Kingdom and United States have access to these vitamins through their diets.
The best way to get necessary nutrients is through the foods we eat, not necessarily through a supplement industry that has little and loose oversight by the U.S. Food and Drug Administration (FDA).
Expectant mothers want the best for their child is a point proven in marketing language, researchers say.
“Pregnant women may be vulnerable to messages about giving their baby the best start in life, regardless of cost,” they conclude. “The marketing of such products does not appear to be supported by evidence of improvement in child or maternal outcomes.”