5 Ways to Lower the Risk of Having a Pregnancy Affected by a Neural Tube Defect

Neural tube defects occur early during pregnancy and happen when the neural tube, which forms the brain and spine, does not close properly. A neural tube defect can be caused by one or more risk factors. While not all causes of neural tube defects are known, you can take steps to improve your chances of having a healthy pregnancy.

  1. If you are pregnant, having a high enough amount of folate in your blood (blood folate concentration) is important to help to prevent a neural tube defect in your developing baby.1
    • Folate is another word for vitamin B9.
    • Blood folate concentration is the amount of folate that can be measured in your blood.
      Lady taking some medicine
    • You can increase the amount of folate in your blood by consuming folic acid, which is one form of folate, in addition to a diet rich in natural folate.
      • It can take several months for the folate levels in your blood to be high enough to help prevent neural tube defects. Therefore, CDC urges all women of reproductive age to get 400 mcg of folic acid each day, in addition to consuming food with folate from a varied diet.
    • Folic acid is the only form of folate that has been shown to help prevent neural tube defects.2-6
    • Folic acid is a specific form of folate that does not generally occur naturally. You can find folic acid in vitamins, fortified foods like rice, pasta, and bread, and some breakfast cereals that are labeled “enriched.”
    • Folic acid is used for food fortification because it is more heat-stable than natural food folate. Heat and light can easily break down natural food folate. Folic acid is better suited for food fortification because many fortified products, such as bread, are baked.7
    • It is difficult for women of reproductive age to get the recommended 400 micrograms (mcg) of folate through diet alone. (See Table 2: https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/)
      • You can get 400 mcg of folic acid each day by taking a vitamin with folic acid in it, eating fortified foods, or getting a combination of the two, in addition to consuming a balanced diet rich in natural food folate.
    • You do not need to consume more than 400 mcg of folic acid unless you have already had a pregnancy affected by a neural tube defect or a doctor has recommended a different amount.
    • For a variety of reasons, neural tube defects affect some groups more than others.
      • Hispanic/Latina women are more likely to have a child born with a neural tube defect, compared to non-Hispanic white and non-Hispanic black women.8, 9

      Learn more about why neural tube defects affect some women more than others >>

  2. Manage pre-existing health conditions before and during your pregnancy.
    • Diabetes
      • If you have diabetes, be sure to keep your blood sugar under control and talk with your healthcare provider to plan your pregnancy.
      • For women with type 1 or type 2 diabetes, high blood sugar around the time of conception increases a baby’s risk of a neural tube defect, other types of birth defects, stillbirth, and preterm birth.

      Learn more about diabetes and pregnancy >>

    • Obesity
      • Obesity (measured as a body mass index) [BMI] of 30 or higher) before pregnancy can increase the chances for complications during pregnancy, including serious birth defects. Even if you are not planning to become pregnant, getting healthy is important and can boost your mood. If you are overweight or obese, talk with your doctor about ways to reach a healthy weight before getting pregnant.

      Learn more about healthy weight >>

  3. Your family health history may have an impact on your developing baby.
    • Family Health History
      • Learn about both parents’ family health histories to give your baby the best start possible. If either you or the baby’s father have a family health history of a birth defect, developmental disability, newborn screening disorder, or genetic disease, your baby might be more likely to have one of these conditions as well. Knowing your baby’s family health history is important so that you can find and address potential health problems early. 

      Learn more about family health history during pregnancy >>

    • Genetic variations
      • Methylenetetrahydrofolate reductase (MTHFR) gene variant
        • A genetic test may have told you that you have a methylenetetrahydrofolate reductase (MTHFR) genetic variant. The MTHFR gene provides instructions for your body to make the MTHFR protein. The MTHFR protein helps your body process folate. Your body needs folate to make DNA, RNA, and proteins.10
        • You may have heard or read that if you have a MTHFR C677T gene variant, you should take other forms of folate (like 5-Methyl THF) but this is not true. Folic acid is the only form of folate that has been shown to help prevent neural tube defects.2-6

      Learn more about the MTHFR gene and folic acid >>

  4. Certain medications are associated with having a pregnancy affected by a neural tube defect. Be sure to talk with your doctor before starting or stopping any medications before and during your pregnancy.
    • Seizure medications
      • Some medications that are used to treat seizures, specifically valproic acid and carbamazepine, have been associated with an increased chance of having a pregnancy affected by a neural tube defect.11-13
        • Valproic acid is a medication used to control seizures in patients with epilepsy. It is also used to treat bipolar disorder and migraines.11
        • Carbamazepine is a medication used to control seizures when treating epilepsy. It is also used to treat bipolar affective disorder, schizophrenia, and other pain disorders.12
      • The most common neural tube defect associated with valproic acid and carbamazepine is spina bifida. Other birth defects associated with use of these medications during pregnancy are heart defects and cleft lip.11 12
    • Pain medication

      Dr. Jennifer Lind

      Watch Dr. Jennifer Lind, a CDC pharmacist, talk about a study that examined outpatient prescriptions filled for opioid medicines (used to treat pain) from a group of reproductive-aged women with public or private insurance in the United States. Medscape allows free unlimited access to materials after registration.

      • A 2017 study from CDC found that women who took non-steroidal anti-inflammatory drugs and opioid pain medicines during early pregnancy were more likely to have babies affected with certain birth defects, including spina bifida, compared with women who took acetaminophen. [Read the Key Findings >>]
      • Opioid use during pregnancy has been shown to increase the chance of having a pregnancy affected by a neural tube defect.14, 15
    • Antibiotics
      • For the health of the mother and baby, antimicrobials, specifically antibacterial drugs, are some of the most commonly used medications to treat infections during pregnancy.
        • Some specific forms of antibiotics, known as sulfonamides, have been shown to be associated with neural tube defects.16
      • Be sure to talk with your doctor before starting or stopping any medications.
    • For questions about medication use during pregnancy, talk with a healthcare professional. You can also contact an expert with MotherToBaby. MotherToBaby information specialists are available by phone, text, email, or live chat.

    Learn more about medication and pregnancy >>

    Learn more about guidelines and recommendations for treating and managing health conditions during pregnancy >>

  5. Overheating or fever can influence the chance of having a neural tube defect-affected pregnancy.
    • Overheating increases the chance of having a baby with a neural tube defect.
      pregnant woman with thermometer in home
    • You can become overheated by having a fever or being exposed to excessive temperatures (like getting in a hot tub) that increase your core temperature.
    • You can help to protect your developing baby by protecting yourself against infections, treating fever promptly, and limiting environmental exposures that increase your core body temperature.17

    Learn more about fever during pregnancy >>

    CDC is dedicated to better understanding the causes of neural tube defects. Understanding the characteristics that are more common among babies with a neural tube defect will help us learn more about the causes and the ways to prevent these types of birth defects from occurring.

    Learn more about data & statistics on birth defects >>

For More Information

For more information, visit the Frequently Asked Questions Folic Acid webpage.

You can also contact CDC-INFO in English or Spanish:


  1. Crider KS, Devine O, Hao L, et al. Population red blood cell folate concentrations for prevention of neural tube defects: Bayesian model. BMJ (Clinical research ed). 2014;349:g4554.
  2. De Wals P, Tairou F, Van Allen MI, et al. Reduction in neural-tube defects after folic acid fortification in Canada. The New England journal of medicine. 2007;357(2):135-142.
  3. Wals P, Tairou F, Van Allen MI, et al. Spina bifida before and after folic acid fortification in Canada. Birth defects research Part A, Clinical and molecular teratology. 2008;82(9):622-626.
  4. AE, Dudas I. Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation. The New England journal of medicine. 1992;327(26):1832-1835.
  5. Berry RJ, Li Z, Erickson JD, et al. Prevention of neural-tube defects with folic acid in China. China-U.S. Collaborative Project for Neural Tube Defect Prevention. The New England journal of medicine. 1999;341(20):1485-1490.
  6. Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group. Lancet (London, England). 1991;338(8760):131-137.
  7. E, Selhub J. Properties of food folates determined by stability and susceptibility to intestinal pteroylpolyglutamate hydrolase action. The Journal of nutrition. 1998;128(11):1956-1960.
  8. Williams J, Mai CT, Mulinare J, et al. Updated estimates of neural tube defects prevented by mandatory folic Acid fortification – United States, 1995-2011. MMWR Morbidity and mortality weekly report. 2015;64(1):1-5.
  9. Canfield MA, Mai CT, Wang Y, et al. The association between race/ethnicity and major birth defects in the United States, 1999-2007. American journal of public health. 2014;104(9):e14-23.
  10. Crider KS, Yang TP, Berry RJ, Bailey LB. Folate and DNA methylation: a review of molecular mechanisms and the evidence for folate’s role. Advances in nutrition (Bethesda, Md). 2012;3(1):21-38.
  11. MotherToBaby. Valproic Acid. 2018; https://mothertobaby.org/fact-sheets/valproic-acid-pregnancy/. Accessed November 20, 2018.
  12. MotherToBaby. Carbamazepine. 2017; https://mothertobaby.org/fact-sheets/carbamazepine-pregnancy/. Accessed November 20, 2018.
  13. Gilboa SM, Broussard CS, Devine OJ, et al. Influencing clinical practice regarding the use of antiepileptic medications during pregnancy: modeling the potential impact on the prevalences of spina bifida and cleft palate in the United States. American journal of medical genetics Part C, Seminars in medical genetics. 2011;157c(3):234-246.
  14. Yazdy MM, Mitchell AA, Tinker SC, Parker SE, Werler MM. Periconceptional use of opioids and the risk of neural tube defects. Obstet Gynecol. 2013;122(4):838-844.
  15. Broussard CS, Rasmussen SA, Reefhuis J, et al. Maternal treatment with opioid analgesics and risk for birth defects. American journal of obstetrics and gynecology. 2011;204(4):314.e311-311.
  16. Crider KS, Cleves MA, Reefhuis J, Berry RJ, Hobbs CA, Hu DJ. Antibacterial medication use during pregnancy and risk of birth defects: National Birth Defects Prevention Study. Archives of pediatrics & adolescent medicine. 2009;163(11):978-985.
  17. Kerr SM, Parker SE, Mitchell AA, Tinker SC, Werler MM. Periconceptional maternal fever, folic acid intake, and the risk for neural tube defects. Annals of epidemiology. 2017;27(12):777-782.e771.