Taking Folic Acid Supplement Before And During Pregnancy Can Prevent Spina Bifida
Question: My cousin has a child who has spina bifida. I am worried that if I get pregnant, my son or daughter may have the same problem. Recently I heard that taking a vitamin could prevent this. Is it true?
Answer:
Thank you for asking this very important question. I believe everyone, especially women of childbearing age, should know about the importance of folic acid in the development of the fetus. Let me begin by explaining what is spina bifida and how we can prevent it.
Spina bifida is a serious birth defect of the brain and the spinal cord. These children are born with an opening in the lower part of their back, exposing an abnormal spinal cord (which is an extension of the brain inside the spine). Shortly after birth, these children need an operation to repair the abnormal spinal cord to prevent infection. Because of the defective spinal cord, most of these children cannot walk or run normally. Some will have trouble controlling their bladder and bowel functions.
The circulation of spinal fluid inside and around the brain of these children is also affected. As a result, extra spinal fluid collects inside the brain and forces the skull to grow much faster than normal. This condition is called hydrocephalus. Almost all children with spina bifida will require an operation to insert a tube (called “shunt”) inside the brain to remove excess spinal fluid. This will reduce the pressure in the brain and allows it to grow normally. Because of these operations, most children with spina bifida have normal intelligence and can learn in school like all other children.
Spina bifida is fairly common. In North America, it occurs in one child out of 1,000 births. It happens more often in some ethnic groups. In families that already have one child with spina bifida, the chance of another child with this condition increases to 3-4%. If your cousin has a child with spina bifida, you do have a higher chance than the general population to carry a child with this problem.
The cause of spina bifida was unknown until recently. In the last 10 years, scientists have found a strong relationship between folic acid in women and spina bifida (as well as other related conditions called neural tube disorders). In a study done in Ireland, women who have low levels of folic acid in their blood have much greater chance of bearing children with spina bifida. By giving these women folic acid, 85% of these defects could be avoided.
Other studies done in Hungary and Ireland produced the same conclusion. Giving folic acid to women before and during pregnancy prevented most, if not all, cases of spina bifida. Folic acid appears to be essential in the development of the brain and spinal cord.
Because of these findings, the Society of Obstetricians and Gynaecologists of Canada recommends that all women of child-bearing age who are likely to become pregnant should take a minimum of 0.4 mg of folic acid daily, starting at least one month before pregnancy. All women with a previous pregnancy affected by neural tube disorder (this includes spina bifida) may benefit from taking 4 mg of folic acid daily. Women who have an increased chance because of their medical condition (like being on certain epilepsy medications which can cause spina bifida), or due to strong family history, should take one to 4 mg of folic acid daily.
In my opinion, it is perfectly fine to take folic acid supplement. Most multivitamins sold in pharmacies contain 0.4 mg of folic acid, the recommended dose for the general public. However, folic acid is present in large amounts in dark green leafy vegetables, whole grain cereals, and bread. Eating these food items can give us a good supply of folic acid, as well as many other essential vitamins, minerals and fibers.
In addition to benefiting women and fetus, some research suggests that folic acid is also important in preventing blockage of blood vessels and heart diseases, as well as some cancer. In United States, there is a strong movement to supplement a staple food, like flour, with folic acid. If this is done, everyone will consume some folic acid that the body needs. However, it is still important to eat a healthy, balanced diet, and this includes vegetables.
[Notes to Readers: Since the publication of this column more than 20 years ago, a few developments have happened. Folic acid fortification is routine in North America; spina bifida is now an uncommon condition in newborn babies; in the last few years, surgeons have started to operate on foetuses with spina bifida diagnosed in prenatal ultrasound to close the defect, the long-term outcome of these children is still unclear, stay tuned….]