Vitamin B12 and folate are two important
micronutrients in the diet that are essential during pregnancy for the normal
development of the fetus. It is important that these micronutrients be taken in
adequate amounts for proper development of the fetus.
How does one assess if the intake of these
micronutrients in the diet is adequate? The simplest way to do so is by
recording the intake on a questionnaire. However, currently, there are no
validated questionnaires to measure vitamin B12 and folate intake.
A study was
conducted in Japan to validate the usability and reproducibility of a
self-administered diet history questionnaire (DHQ) in pregnant women. The 22-page questionnaire
measures intake of energy, folate and vitamin B12 over the past 1 month.
The study was conducted in 2 hospitals in Japan.
Women in their second trimester, that is, between four and six months of
pregnancy, were included in the study. Blood samples to measure vitamin B12 and
folate levels were taken along with the blood samples routinely obtained during
pregnancy. Each woman was given the questionnaire, which was completed within 7
days of the blood sample.
To assess whether the results of the questionnaire
are reproducible, some women were asked to complete the questionnaire twice
during the study.
The final analysis was carried out on data from 167
pregnant women. Reproducibility was determined based on the questionnaires
submitted by 58 women.
The study found that there was some correlation
between intake and serum levels of vitamin B12 and folate. Thus, the DHQ can be used as a screening test in pregnant women in
Japan to detect vitamin B12 and folate deficiency. This is especially true
for women without nausea. The results were found to be reproducible when
repeated twice in some participants. The study, however, does have its
limitations. Further studies may be required to establish the routine use of
the diet history questionnaire in pregnant women in Japan and elsewhere.
1. Mie Shiraishi et al. Validity and reproducibility of folate and
vitamin B12 intakes estimated from a self-administered diet history
questionnaire in Japanese pregnant women. Nutrition Journal 2012, 11:15