NTDs and Pregnancy – Folic Acid Recommendations

SUMMARY:

Several professional organizations provide guidance on neural tube defects (NTDs) including recommendations related to screening, management and delivery. The USPSTF has reaffirmed its recommendation that folic acid supplementation prevents NTDs in offspring. Evidence of potential harms to mother or infant is no greater than small.

PROFESSIONAL RECOMMENDATIONS

• USPSTF
  • All women who are planning or capable of pregnancy should take a daily supplement containing 0.4 to 0.8 mg (400 to 800 µg) of folic acid
  • Approximately 50% of pregnancies in the US are unplanned so it is best to already be on folic acid prior to pregnancy
• ACMG
  • Daily folic acid intake of 400 µg (0.4 mg) is recommended in all women of child-bearing age
    • If planning pregnancy, start at least 4 weeks prior to planned conception
  • Women at High risk: 4,000 µg (4 mg) of daily folic acid supplementation at least 12 weeks prior to conception
    • Then continue with 400 µg (0.4 mg) after 12 weeks gestation

Note: ACMG highlights that folic acid supplementation reduces risk but not entirely prevent NTDs even among women who are fully compliant

• ACOG, CDC, AAFP, AAP, Health and Medicine Division of the National Academies (formerly the Institute of Medicine), US Public Health Service, American Academy of Neurology
  • Women who are capable of becoming pregnant should take at least 0.4 mg (400 µg) of folic acid daily

• ACOG, CDC, and several other organizations
  • Women with a history of neural tube defects, or has a partner with an NTD or a partner who has had a child with an NTD or other high-risk factors take 4 mg (4000 μg) of folic acid daily

Note: While USPSTF focuses on prevention of NTD, other organizations also stress the prevention of other birth defects such as heart defects, urinary tract anomalies and oral facial clefts

High risk factors include the following

• Patient has a previously NTD-affected pregnancy
• Patient herself is affected
• Patient with a first- or second-degree relative with a NTD
• Diabetes mellitus type 1
• Obesity
• Particular antiseizure medications (eg, valproic acid)

NOTE: Folic acid may not prevent NTDs in diabetic pregnancies, especially if not well controlled | Likewise regarding obesity and antiepileptic medications may also be folate-resistant

Learn More – Primary Sources:

USPSTF Statement: Folic Acid Supplementation for the Prevention of Neural Tube Defects

ACOG Practice Bulletin 187: Neural Tube Defects

ACMG Policy Statement on folic acid and neural tube defects

ACMG Focused Revision: Policy statement on folic acid and neural tube defects

CDC: Folic Acid – Facts for Clinicians

Locate a Genetic Counselor or Genetics services:

Genetic Services Locator-ACMG

Genetic Services Locator-NSGC

Genetic Services Locator-CAGC

Locate a Maternal Fetal Medicine Specialist

Maternal Fetal Medicine Specialist Locator-SMFM

Related ObG Topics:

Neural Tube Defects: Definitions, Key Clinical Findings and Management

Gastroschisis – Detection and Implications

Omphalocele – An Early Ventral Wall Defect

Maternal Overweight, Obesity and Congenital Malformations – How Strong is the Link?

Antiepileptic Drugs: What is the Impact on Risk for Birth Defects

How Does Fetoscopic Repair for Open Neural Tube Defects Compare to the Open Approach?