The Effect of Folic Acid Supplementation and Pregnancy on the Folate Forms in Red Blood Cells

December 3, 2013 updated by: Brenda Hartman, The Hospital for Sick Children
The purpose of this cross-sectional study was to examine whether or not physical changes or adaptations occur in response pregnancy or to the higher intakes of folic acid from supplementation typically consumed during the reproductive period.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Higher folate requirements during pregnancy to support growth and development are well established but it is unknown what metabolic changes occur in 1-carbon metabolism to provide sufficient nucleotides for DNA/RNA synthesis. Periconceptual folic acid (FA) supplementation and fortification of the food supply have been shown to reduce the risk of pregnancies with neural tube defects but conversely expose women to high FA intakes for extended periods of time. The purpose of this cross-sectional study is to establish if physiological adaptations occur in folate metabolism in response to pregnancy or higher intakes of FA typically consumed among women during the reproductive period. A convenience sample of thirty-two women (n=8/group) were recruited to compare the total concentrations and forms of folate (tetrahydrofolate [THF], 5-methylTHF, 5-formylTHF and 5, 10-methenylTHF) in red blood cells in four groups: a) pregnant women (PW, 30-36 weeks gestation) taking 1.0 mg of FA b) non-pregnant women (NPW) taking 0 mg of FA c) NPW taking 1.0 mg FA and d) NPW taking 5.0 mg FA. Blood samples were taken at a single time point and compared across groups. Total red blood cell concentrations were measured using both microbiological assay and liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. LC/MS/MS analysis was used to determine folate form concentrations.

Study Type

Observational

Enrollment (Actual)

32

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Ontario
      • Toronto, Ontario, Canada, M5G 1X8
        • The Hospital For Sick Children

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

20 years to 35 years (ADULT)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

Female

Sampling Method

Non-Probability Sample

Study Population

women of reproductive age

Description

Inclusion Criteria:

  1. pregnant women-

    • between 30 to 36 weeks gestation
    • taking 1 mg folic acid in a multisupplement
  2. non-pregnant women-

    • not pregnant
    • taking either 0, 1 or 5 mg folic acid in a multisupplement

Exclusion Criteria:

  • Taking any medications known to interfere with folate absorption at the time of sampling (ie. Antibiotics [ can be enrolled into study if they will be off them at least two weeks prior to study commencement], methotrexate, aminopterin)
  • Those with a history of any disorders or conditions that could interfere with folate absorption or metabolism from either dietary or supplement sources such as the history/presence clinically significant gastrointestinal disease (chronic diarrhea, inflammatory bowel disease, partial gastrectomy), unresolved GI symptoms(diarrhea/vomiting), steatorrhea or other conditions that interfere with absorption, distribution, metabolism or excretion of folic acid.
  • Those with preexisting conditions (pre-existing maternal diabetes; insulin-dependent diabetes; previous child with neural tube disorder (NTD), cleft-lip/palate or heart defect; epilepsy and/or seizure disorders) that can increase the risk of pregnancy complicated by NTD.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
pregnant women
pregnant women taking 1 mg folic acid;
subjects take multivitamin supplement containing folic acid. Women were enrolled based on whether or not they were taking supplements.
non-pregnant women
non-pregnant women taking 0mg folic acid;
non-pregnant women 2
non-pregnant women taking 1 mg folic acid
non-pregnant women 3
non-pregnant women taking 5 mg folic acid

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Red blood cell folate concentrations - tetrahydrofolate (THF)
Time Frame: At the point of participation (this is a single visit, single test study)
Bood samples were taken once at the point of participation and compared 1) pregnant women (between 30-36 weeks gestation) and non-pregnant women who were taking supplements 2) 0 mg folic acid 3) 1 mg FA, 4) and 5 mg FA. Those who were taking supplements were taking them for a minimum of 30 weeks.
At the point of participation (this is a single visit, single test study)

Secondary Outcome Measures

Outcome Measure
Time Frame
Red blood cell folate concentrations - 5-methyltetrahydrofolate (5-methylTHF)
Time Frame: At the point of participation (this is a single visit, single test study)
At the point of participation (this is a single visit, single test study)
Red blood cell concentrations - 5-formyltetrahydrofolate (5-formylTHF)
Time Frame: At the point of participation (this is a single visit, single test study)
At the point of participation (this is a single visit, single test study)
Red blood cell folate concentrations - 5,10-Methenyltetrahydrofolate (5,10-methenylTHF)
Time Frame: At the point of participation (this is a single visit, single test study)
At the point of participation (this is a single visit, single test study)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Deborah L O'Connor, PhD, The Hospital For Sick Children

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

May 1, 2008

Primary Completion (ACTUAL)

October 1, 2008

Study Completion (ACTUAL)

April 1, 2010

Study Registration Dates

First Submitted

November 27, 2012

First Submitted That Met QC Criteria

December 3, 2012

First Posted (ESTIMATE)

December 4, 2012

Study Record Updates

Last Update Posted (ESTIMATE)

December 5, 2013

Last Update Submitted That Met QC Criteria

December 3, 2013

Last Verified

December 1, 2013

More Information

Terms related to this study

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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