Folic Acid Doesn't Increase Miscarriage Risk
Sept. 6, 2001 -- Though the benefits of taking folic acid supplements to prevent certain birth defects is firmly established, a study from several years ago found that women who took a multivitamin containing 800 micrograms of folic acid before and during early pregnancy had an increased risk of miscarriage.
But now a new study, published in the Sept. 8 issue of the Lancet, shows no increased risk of miscarriage among women who took 400 micrograms of folic acid before and during early pregnancy. In the study, women who had or had not taken folic acid supplements before and during the first trimester of their pregnancy had roughly the same rate of miscarriage, report researchers from the CDC in Atlanta and Peking University Health Sciences Center in Beijing.
Current recommendations state that all women who can become pregnant take a multivitamin that contains 400 micrograms of folic acid every day, beginning before conception and continuing into the early months of pregnancy, as part of a healthy diet including foods containing folic acid, such as leafy green vegetables, orange juice, peanuts, beans, and fortified grains.
Experts agree that the new study results further reinforce this message.
Folic acid supplementation before conception and during the first trimester of pregnancy is known to reduce risk for neural tube birth defects. Such birth defects including spina bifida and anencephaly affect 4,000 pregnancies per year, resulting in 2,500 to 3,000 U.S. births annually.
Spina bifida, or open spine, occurs when the backbone never closes completely and is a leading cause of childhood paralysis. Anencephaly is marked by a severely underdeveloped brain and skull.
Half of all pregnancies in the U.S. are unplanned. The neural tube forms by 28 days, so women must take folic acid on a daily basis before conception since weeks can go by before pregnancy is confirmed.
"[The new study] is good news," says study author R.J. Berry, MD, a medical epidemiologist at the CDC. "Taking folic acid before and during early pregnancy is safe and doesn't increase risk of miscarriage."