Maternal serum vitamin B12, folate and homocysteine and the risk of neural tube defects in the offspring in a high-risk area of China

Public Health Nutr. 2009 May;12(5):680-6. doi: 10.1017/S1368980008002735. Epub 2008 Jun 12.


Objective: To examine the association between the risk of neural tube defects (NTD) and maternal serum vitamin B12, folate and homocysteine in a high-risk area of China.

Design: A case-control study was carried out in Luliang mountain area of Shanxi Province.

Subjects/setting: A total of eighty-four NTD pregnancies and 110 matched controls were included in the study; their serum vitamin B12 and folate concentrations were measured by chemiluminescent immunoenzyme assay and total homocysteine concentrations by fluorescent polarisation immunoassay.

Results: Serum vitamin B12 and folate concentrations were lower in NTD-affected pregnant women than in controls (P < 0.01). Serum total homocysteine was higher in the NTD group than in controls at less than 21 weeks of gestation (P < 0.01). Adjusted odds ratios revealed that women with lower vitamin B12 (adjusted OR=4.96; 95 % CI 1.94, 12.67) and folate (adjusted OR=3.23; 95 % CI 1.33, 7.85) concentrations had a higher risk of NTD compared to controls. Based on dietary analysis, less consumption of meat, egg or milk, fresh vegetables and fruit intake would increase the risk of NTD.

Conclusions: Lower serum concentrations of folate and vitamin B12 are related to the increased risk of NTD in high-risk populations. Both folate and vitamin B12 intake insufficiency could contribute to the increased risk of NTD. A dietary supplement, combining folate and vitamin B12, might be an effective measure to decrease the NTD incidence in these areas.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Case-Control Studies
  • China
  • Diet
  • Female
  • Folic Acid / blood*
  • Homocysteine / blood*
  • Humans
  • Infant, Newborn
  • Luminescent Measurements
  • Maternal Nutritional Physiological Phenomena*
  • Neural Tube Defects / blood*
  • Neural Tube Defects / diagnostic imaging
  • Neural Tube Defects / epidemiology
  • Neural Tube Defects / etiology*
  • Pregnancy / blood
  • Pregnant Women
  • Risk Factors
  • Ultrasonography
  • Vitamin B 12 / blood*
  • Young Adult


  • Homocysteine
  • Folic Acid
  • Vitamin B 12