Fortification Helps Ensure Maternal and Infant Health

Women who may become pregnant need adequate nutrition to prepare for the additional physical demands of pregnancy.

Nutritional Needs

Women need 400 micrograms of folic acid (vitamin B9) daily before conception and for at least 28 days after conception to reduce the risk of the infant having a severe birth defect of the brain or spine. These birth defects are called neural tube defects (NTDs).

In early pregnancy, a woman’s need for iron increases from 0.8 to 7.5 milligrams per day. In addition, iron, riboflavin, folic acid, zinc, vitamin A and vitamin B12 prevent specific types of anemia, which in pregnancy is dangerous for both the mother and the baby.

Consequences of Deficiencies

Birth defects

Adequate folic acid intake can prevent most cases of three birth defects: spina bifida, anencephaly, and cephalocele.

In spina bifida, the baby’s spine does not form correctly. In mild cases, permanent loss of some sensation or movement occurs. Severe cases include paralysis and varying degrees of loss of bowel and bladder control. Children born with spina bifida will likely undergo a lifetime of surgeries and face many health issues. Spina bifida cannot be cured.

With anencephaly, the brain does not form properly. Pregnancies affected by anencephaly are often miscarried. Babies born with anencephaly die shortly after birth.

With cephalocele, part of the brain protrudes through the skull. This is a rare birth defect.


Pregnant women with severe anemia are twice as likely to die during or shortly after pregnancy than non-anemic women. Also, anemic women in low and middle-income countries have a significantly higher risk of having a low-birth-weight infant than non-anemic women. Low birth weight means less than 2500 grams or 5.5 pounds at birth; infants that small are prone to death and diseases while they are young. If they survive, they are more at risk for poor mental development in childhood and chronic health problems such as diabetes and heart disease later in life.

Extent of the Problem

  • Globally about half of pregnancies affected by a brain or spine birth defect in 2015 resulted in termination of the pregnancy or still births. Of the live births, about 75% resulted in death before the child's fifth birthday.
  • About 230,000 brain and spine birth defects could be prevented every year if women had adequate intake of folic acid before and immediately after conception.
  • Anemia is estimated to affect 32.4 million pregnant women (including 0.8 million pregnant women with severe anemia) and 496.3 non-pregnant women.
  • From 15% to 20% of all births worldwide, representing 20 million infants a year, are low birth weight.

Benefits of Fortification

Women who are not planning a pregnancy are not likely taking prenatal supplements, and most people do not consume the equivalent of 400 micrograms of folic acid from unfortified food. Taking folic acid supplements after the pregnancy is confirmed is usually too late to protect against brain and spine birth defects. On the other hand, women who regularly consume foods fortified with folic acid are less likely to have an infant with a brain or spine birth defect. 

While fortification does not provide all the iron a woman needs in pregnancy, consuming foods fortified with iron helps them enter pregnancy with adequate nutrient stores. This makes it less likely that they will develop severe iron deficiency during pregnancy.

Safety Concerns

Some people have been told to avoid folic acid because they have a variation of the MTHFR (methyltetrahydrofolate reductase) enzyme. These individuals process folic acid more slowly than those without the variation, and the Centers for Disease Control and Prevention recommends that people with the MTHFR variation continue to take folic acid.

A review of the safety of folic acid published in 2018 noted that, "Current folic acid fortification programs support public health in populations, and the exposure levels are informed by and adherent to the precautionary principle." Also see this literature review from December 2016.

Fortifying food with iron helps consumers avoid the consequences of iron deficiency with "remarkably little risk of adverse health effects."

Sustainable Development Goals (SDG)

Periconception nutrition addresses the Sustainable Development Goal 3 for reproductive, maternal, and newborn heath. Adding nutrients to grains commonly consumed by women of reproductive age is a strategy to reduce maternal and infant mortality and improve maternal and newborn health.

Top Photo Credit: @UNICEF

What's the best thing since sliced bread? Adding folic acid to flour to prevent birth defects like spina bifida and anencephaly.

Hear how Costa Rica fortified foods to prevent anemia from iron deficiency.

Thirty-six studies from 13 countries compared the prevalence of neural tube defects (NTDs) before and after large-scale programs to fortify flour with folic acid. Between 1 and 3 milligrams of folic acid were added to each kilogram of wheat flour alone or in combination with maize flour.

The prevalence of NTDs, which are brain and spine birth defects, before fortification ranged from 3.8 to 43.7 per 10,000 births. The prevalence became less variable after flour was fortified with folic acid (3.0 to 24.3 per 10,000 births).

Most studies found a statistically significant decline in the number of NTDs between pre- and post-fortification periods, demonstrating that fortifying flour with folic acid reduced the NTD prevalence.

See our summary of the studies and downloand a spreadsheet of the documents reviewed.