What are the effects of folic acid or vitamin B9 in pregnancy?

By (embryologist) and (embryologist).
Last Update: 07/21/2023

Folic acid, also known as vitamin B9, folatine or vitamin M, among other names, is a water-soluble vitamin with an important role in women of childbearing age and during pregnancy. This vitamin prevents possible neural defects in the fetus, such as spina bifida. In addition, folic acid helps in the production of blood cells and participates in the production of genetic material, among other functions.

Therefore, it is recommended to take a certain amount of folic acid daily in both women who are seeking pregnancy and those who are not. The recommended dose of folic acid in adults is 2mg and in pregnant women or women who are planning to become pregnant in the near future is 4-6 mg.

What is the folic acid?

Folates are a type of B vitamin, B9 in particular, which can only be obtained from the diet or, failing that, from artificially manufactured compounds. This last presentation is what is known as folic acid. This vitamin can be administered orally as well as parenterally.

Among the functions performed by folic acid in the human body is its involvement in the production processes of genetic material and its participation in numerous bodily functions (such as the formation of red blood cells). Folic acid also helps to maintain the functions of the intestinal tract and to prevent certain types of anemia and even cancer (colon, breast).

In addition, folic acid plays an important role in pregnancy, as it helps to prevent possible malformations in the baby's neural tube, thus reducing the possibility of the baby having spina bifida.

Benefits of folic acid in pregnancy

In the very early stages of pregnancy, folic acid is vital for proper fetal development. A deficiency of this will cause the cell division capacity to be reduced and the fetus will not grow as it should.

Therefore, those women who are thinking of becoming pregnant should have the recommended doses of folic acid, since:

  • Reduces the risk of delivering a premature or underweight baby.
  • Helps prevent neural tube defects, the tube that allows the formation of the spinal cord and brain.

If folic acid levels in the pregnant woman are not adequate, fetal malformation may occur, especially in the first weeks of pregnancy. The most common is spina bifida. It is an incomplete closure of the neural tube, resulting in irreversible and permanent disability.

Another benefit of folic acid intake during pregnancy is that it prevents the pregnant woman from suffering from anemia. In addition, vitamin B9 also participates in the secretion of serotonin, thus reducing the possibility of postpartum depression.

Sources of folic acid

The World Health Organization (WHO) recommends that pregnant women take around 400-600 μg of folic acid per day, but it is always necessary to take into account the doctor's indications as well. Sometimes, the specialist advises to take folic acid together with iron supplements during pregnancy.

Some foods rich in folic acid that women can consume during pregnancy are:

  • Green leafy vegetables such as arugula, watercress, spinach, chard or parsley.
  • Legumes such as beans and chickpeas.
  • Nuts (chestnuts, walnuts, hazelnuts and almonds).
  • Vegetables such as broccoli.

Although these foods are high in folic acid, their concentration may be different depending on the method of preparation. For example, the amount of folic acid provided by raw spinach is 192 μg per 100 grams; whereas if cooked, it is reduced to 140 μg per 100 grams of spinach.

In any case, the amount of folic acid acquired through food is usually not sufficient for the pregnant woman, so it is common to take vitamin supplements.

FAQs from users

At what time should pregnant women take folic acid?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

The best time to take folic acid will depend on the situation of the individual pregnant woman. Many specialists advise taking folic acid first thing in the morning, i.e. at breakfast. However, if the pregnant woman suffers from morning sickness and vomiting, it is best to take folic acid in the evening.

Therefore, this vitamin can be taken at any time of the day without any problem, but it is advisable to follow the specialist's instructions.

What are the causes of folic acid deficiency?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

There are several reasons why people may be deficient in folic acid in their bodies. These include:

  • Chron's disease or coeliac disease, as these conditions prevent the intestinal absorption of vitamin B9.
  • Eating overcooked vegetables.
  • Taking birth control pills.
  • Haemolytic anaemia.
Imagen: Causes of folic acid deficiency

In addition, the administration of certain medications can also lead to folate deficiency in the body.

Suggested for you

In addition to folic acid, the pregnant woman should have good levels of other vitamins. In the following link you can read more information on this topic: What vitamins should be taken during pregnancy?

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Stephen Z Levine, Arad Kodesh, Alexander Viktorin, Lauren Smith, Rudolf Uher, Abraham Reichenberg, Sven Sandin. Association of Maternal Use of Folic Acid and Multivitamin Supplements in the Periods Before and During Pregnancy With the Risk of Autism Spectrum Disorder in Offspring. JAMA Psychiatry. 2018 Feb 1;75(2):176-184. doi: 10.1001/jamapsychiatry.2017.4050 (View)

FAQs from users: 'At what time should pregnant women take folic acid?' and 'What are the causes of folic acid deficiency?'.

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Authors and contributors

 Clara Miret Lucio
Clara Miret Lucio
B.Sc., M.Sc.
Bachelor's Degree in Pharmacy from the University of Valencia (UV). Master's Degree in Biotechnology of Human Assisted Reproduction from the UV. Experience as a pharmacist and embryologist specialized in Reproductive Medicine at Valencian Infertility Institute (IVI), and currently at Equipo Juana Crespo (Valencia, Spain). More information about Clara Miret Lucio
 Marta Barranquero Gómez
Marta Barranquero Gómez
B.Sc., M.Sc.
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH). More information about Marta Barranquero Gómez
License: 3316-CV

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