Folic acid: learn why this nutrient is essential during your pregnancy

Although we tend to use the terms folic acid and folate interchangeably, it is important to differentiate the two of them: folate is a water-soluble B vitamin (B9) that occurs naturally in foods such as liver, green leafy vegetables, oranges and legumes, whereas folic acid is the synthetic form of folate found in supplements and added to fortified foods.

Mammals, as well as other animals, do not have the capacity to synthesise folates, so we must obtain them from our diet. However, the daily intake of folates is generally lower than the amounts recommended by health authorities for pregnant women, so an external supply of these nutrients must be taken in the form of vitamin supplements.

In Spain, the General Directorate of Public Health of the Ministry of Health and Consumer Affairs offers the following recommendations to pregnant women:

•  A woman who has not had a pregnancy affected by a neural tube defect (or NTD) before and who is planning to become pregnant should take 0.4 mg (400 micrograms) of folic acid per day for single pregnancies.

• Women who have had a previous pregnancy affected by a neural tube defect should take 4 mg/day of folic acid.

• In both cases, folic acid supplements must be taken at least one month before pregnancy and at the very least during the first three months of pregnancy. A diet rich in folate- containing foods should also be followed.

Patients who have been treated with assisted reproduction techniques will have been taking folic acid since before they became pregnant. However, in a spontaneous pregnancy, it is usually less frequent for women to have been taking folic acid beforehand, and they usually start taking it as soon as they find out they are pregnant.

However, it is very important to take folic acid before conception and on a daily basis, as there is no significant reduction in the risk of neural tube defects when the supplement is taken irregularly or from the second month of pregnancy.

Folate intake, together with multivitamin complexes throughout pregnancy (provided they do not contain fat-soluble vitamins above the recommended daily doses), reduces the incidence not only of neural tube defects but also of cardiac, urinary, orofacial (cleft lip, for example) and limb malformations, and pyloric stenosis.