Do Prenatal Vitamins Prevent Miscarriages?

What the Research Says About Prenatals and Pregnancy Loss

Ultrasound and prenatal vitamins
Getty Images/Jamie Grill

You're probably aware that prenatal vitamins are important for a developing baby's health, but you may wonder if these vitamins can help prevent a miscarriage, too. You may be especially curious about prenatal vitamins and miscarriage risk if you've experienced a pregnancy loss and are looking for ways to ensure that your next pregnancy is successful. 

What the Evidence Says About Prenatal Vitamins and Miscarriage Risk

Prenatal vitamins are usually recommended during a woman's pregnancy to prevent birth defects.

The evidence on prenatals and decreased miscarriage risk has been mixed. 

Some studies have found a link and others have not.

For example, a study from the University of North Carolina-Chapel Hill published in 2009 found that women who took vitamins before or during pregnancy had a 57 percent lower risk of miscarriage compared to women who did not take vitamins. The benefits of vitamin supplementation on miscarriage risk - if there are any - may be due to the overall better health of women who choose to take them.

Other studies have shown no benefit of vitamins on miscarriage risk. One study of Danish women even found an increased risk of early fetal death in women who took multivitamins, although the study authors could not explain the association and cautioned that more research was needed.

The most definitive answer may come from the most recent systematic review of studies on vitamin supplementation in pregnancy.

This review, published in 2011, looked at 28 studies that altogether included more than 96,000 women. It concluded that "taking any vitamin supplements prior to pregnancy or in early pregnancy does not prevent women experiencing miscarriage or stillbirth."

There was another interesting finding of this review: Women who took vitamins before or during their pregnancy had an increased chance of a multiple pregnancy (such as twins).

How Prenatal Vitamins Can Help During Pregnancy

Prenatal vitamins are multivitamins specially formulated for pregnant women. Regardless of whether or not prenatal vitamins can prevent a miscarriage, they are good for your baby's development once you become pregnant.

During pregnancy, your body's needs for certain nutrients (such as folic acid, iron, and calcium) increase, and it can sometimes be hard to know for sure that you're getting enough in your diet. This is especially true for those of us who don't always eat a perfectly balanced diet.

It is well established that having adequate intake of folic acid can reduce your risk of having a baby with neural tube defects, and there may also be a link between low folic acid and miscarriage

If you're pregnant, the safest bet is to take your prenatals and talk to your doctor for recommendations for a particular brand or formulation that will work for you.

Vitamins Before Pregnancy

It's recommended that women start taking folic acid supplements (400 micrograms daily) before they start trying to get pregnant.

It's important to start taking these before your baby is conceived because the neural tube defects spina bifida and anencephaly usually occur in the first month after conception.

The following foods are also rich in folic acid:

  • leafy green vegetables
  • citrus fruits
  • beans
  • breads
  • cereals
  • rice
  • pastas


Folic Acid. The American Pregnancy Association. July 2015.

Nohr, E.A., Olsen, J., Bech, B.H., et al. (2014).  Periconceptional intake of vitamins and fetal death: a cohort study on multivitamins and folate. International Journal of Epidemiology.

Reem, H., Olshan, A.F.,Herring, A.H., et al. (2009). Self-reported Vitamin Supplementation in Early Pregnancy and Risk of Miscarriage. American Journal of Epidemiology. 

Rumbold, A., Middleton, P., Pan, N., et al. (2011). Vitamin supplementation for preventing miscarriage (Review). The Cochrane Library.

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