An Essential Vitamin for Women of Childbearing Age: The Folate/Folic Acid Story

- Clinician's Corner

By: Dr. Patricia Penovich, EFMN Professional Advisory Board Chair

This story is for all women who have the potential to conceive and bear a child, whether she has epilepsy or not. The special emphasis for women with epilepsy is because these young women are usually taking anti-seizure medications (ASMs) to aid in the control of their seizures and there are special circumstances described below for some of these ASMs.

Am I a woman of childbearing age?  It is safe to say that any age between when menses [when the “monthly period” starts] and the completion of menopause when the ovaries stop functioning totally [defined as one year after the period stops].  So a woman may potentially become pregnant from age 10-13 when her period starts to as long as age 45-55 when it is finally over. 

Why should I take Folate (Folic acid) as a vitamin supplement?” Folate, a B vitamin, is critically important in the development of the fetal nervous system beginning within the first 1-2 weeks after conception. It is at this time that the earliest spinal cord and brain development begins resulting in the closing of the structure called the neural tube. Folate deficiency results in a high risk of having an infant with a neural tube malformation, such as when the spinal cord does not properly close, a condition called spina bifida, or a condition where the skull and the brain coverings are not closed. Later in the third trimester of pregnancy, folate is again very important in the migration of the cells to the proper locations throughout the brain and to their future function.

When should I take Folate?  Most women do not know they are pregnant until they miss a period or even later. For some women who have irregular cycles, this can be hard to figure out. It takes about 3 weeks to get enough folate into the mother’s system. Therefore, you would have to take folate for 3 weeks before you get pregnant for the infant to have the folate needed early on. The reality is that more than 50% of pregnancies are unplanned.  Therefore, a woman should take folate every day as a “just in case, because you never know when” protection for her baby. This applies to every woman unless she has had her uterus removed (hysterectomy) or her fallopian tubes tied.

How do I get folate and how much do women need and/or should take? The United States began supplementing grains with flour in the early 1990s, resulting in a decrease in the incidence of new spina bifida in the population in the US. Folic acid can be found in leafy greens, citrus fruits, and legumes, as well as enriched foods like bread, pasta, rice, or breakfast cereal. Incorporating these foods may not meet the folic acid content required for a developing fetus.  

The usual amount of folic acid or folate in a woman’s once-a-day multivitamin is 0.4 milligrams. A prenatal vitamin tablet contains 0.8 milligrams. The standard recommendation is 0.4 mg per day and 0.8 mg per day when you are pregnant.  

What dose should a woman with epilepsy take and why? Women with epilepsy are counseled to take a larger dose if they are taking valproate (Depakote, Depakene, valproic acid) due to an increased risk of up to 5-6 times the general population of having a baby with spina bifida. The reason the valproate produces the higher risk is not completely understood. If any woman has had an infant previously with spina bifida, the recommendation for her is to take the higher dose as well. The actual higher dose amount that should be taken is under some recent discussion. Unfortunately, there is no actual study that has been performed to settle this issue scientifically. In the past the higher dose has ranged between 1-4 mg per day and some providers use 5 mg. Antiseizure medications that induce the liver metabolism of folate are phenytoin (Dilantin), phenobarbital, and carbamazepine (Tegretol). Women on these ASMs should take a routine daily dose that is higher, for example, 0.8 -1 mg per day, because the actual effective amount available after the liver metabolism is roughly 1/3-1/2 the amount ingested. For example, a woman taking carbamazepine would need 1 mg per day which would end up giving her a dose after metabolism of 0.5 mg per day.

In summary, every woman with or without epilepsy should begin daily vitamin supplementation containing folic acid (folate) and continue to do so until they have completed menopause. The dose may be adjusted due to specific co-medications you may be taking and when or if you are pregnant. Folate is important. It aids in the structural development of the nervous system and studies show that children whose mothers took folate supplementation perform significantly better on cognitive developmental and IQ tests than children whose mothers did not take it.