Folate is widely distributed in foods (green-leafy vegetables, fruits, liver, bread etc.). An inadequate dietary folate intake results in a reduction of cell division, leading to anemia, reduced levels of immune cells and reduced ability of blot clotting. An increased intake of folic acid in women before conception is associated with increased levels of progesterone and ovulation, reducing the risk of ovulation disorders, since folate seems to be important for oocyte quality and maturation. Folic acid, vitamin B12 and vitamin B6 together reduce levels of an amino acid called homocysteine. Clinical studies have shown that low folate levels and high homocysteine levels are a risk factor for recurrent early-term abortions. The synthetic version of folate is called folic acid and it is well absorbed.
Nervous system defects in the baby can be effectively prevented with folic acid supplementation prior to conception. Supplementation of folic acid, done in 15 human trials, prior to pregnancy showed a 72% reduction in risk of development of neural tube defects and a 68% reduction in risk of recurrence. In addition, folic acid supplementation during pregnancy improved mean birth weight, while low levels of folate resulted in increased risk of placental abruption (separation of placenta from the uterus, leading to dysfunction of the placenta and bleeding). Folic acid (400 microgram per day), vitamin B6 (1.9 mg) and B12 (2.6 microgram per day) supplementation is the most effective when taken 6-8 weeks prior to pregnancy.