A 32-year-old woman comes to the office with her 2-year-old son, whom you have been treating for spina bifida. The mother says that she would like to have another child, but she is concerned about the possibility that her future children may also have spina bifida. She currently takes a multivitamin containing 400 µg of folic acid. You advise her that to minimize the risk for having a second child with spina bifida she should do which of the following?
A) Continue her current vitamin regimen, preconceptionally and during the first trimester
B) Increase her dietary intake of folate-rich foods, preconceptionally and during the first trimester
C) Take additional supplementary folic acid as soon as she becomes pregnant
D) Take additional supplementary folic acid, preconceptionally and during the first trimester
E) Take two multivitamins daily, preconceptionally and during the first trimester
The correct answer and explanation is :
Correct Answer: D) Take additional supplementary folic acid, preconceptionally and during the first trimester
Explanation:
Spina bifida is a neural tube defect (NTD) that results from the failure of the neural tube to close properly during embryonic development, typically within the first 28 days of gestation, often before a woman even knows she is pregnant. The most effective way to reduce the risk of NTDs is adequate folic acid supplementation during the periconceptional period—that is, before conception and during early pregnancy.
For women at average risk, the recommended daily folic acid intake is 400 µg (0.4 mg). However, women with a previous child affected by a neural tube defect are considered high risk and require a higher dose of folic acid. In these cases, the Centers for Disease Control and Prevention (CDC) and the American College of Obstetricians and Gynecologists (ACOG) recommend a daily dose of 4 mg (4000 µg) of folic acid. This supplementation should start at least one month before conception and continue through the first trimester of pregnancy.
Option D is the correct answer because it emphasizes the need for additional folic acid supplementation before conception and during the first trimester, which is critical for preventing neural tube defects in a subsequent pregnancy. Simply taking a multivitamin containing 400 µg of folic acid (Option A) or increasing folate-rich foods (Option B) is insufficient for high-risk women. Starting folic acid after conception (Option C) may be too late, as neural tube development is largely complete by the time pregnancy is confirmed. Option E, taking two multivitamins, may not reliably provide the needed 4 mg dose and lacks specific guidance.
Therefore, high-dose folic acid (4 mg daily) started preconceptionally and continued through the first trimester is the best practice for reducing recurrence of spina bifida in future pregnancies.