Natural Folate vs. Synthetic Folic Acid in Pregnancy

April 11, 2023 updated by: Crystal Karakochuk, University of British Columbia

Is Natural Folate as Effective as Synthetic Folic Acid in Increasing Serum and Red Blood Cell Folate Concentrations During Pregnancy? A Proof-of-concept Pilot Study

In this two-arm, double-blind randomized pilot study, the investigators will recruit 60 generally healthy, low-risk pregnant women aged 19-42 years living in Vancouver, Canada. Participants will be randomized to supplement with either 0.6 mg/day folic acid or an equimolar dose (0.625 mg/day) of (6S)-5-methyltetrahydrofolic acid for 16-weeks of their pregnancy. Randomization will occur at 8-21 weeks gestation (after neural tube closure) to reduce the risk of harm should the natural folate prove less effective. All participants will also receive a prenatal multivitamin not containing any form of folate, to ensure adequacy of other nutrients (e.g. iron) required during pregnancy. Three-hour fasting venous blood samples will be collected at baseline and endline to measure serum and red blood cell folate, unmetabolized folic acid and other related biomarkers. Women will be given the option to continue supplementing until 1-week postpartum, and provide a small (3mL) breastmilk sample and blood sample in order to measure differences in folates in breastmilk and postpartum folate. These pilot data will be used to inform a definitive trial regarding the most effective form of folate supplementation for mothers and their babies.

Study Overview

Detailed Description

A sample size of 50 women (25 in each group) are required to reliably estimate the distributions of serum and red blood cell folate. Thus, to account for drop outs or loss to follow up, a total of 60 women (30 in each group) will be recruited.

Aim 1: To establish the mean ± standard deviation change in serum folate, red blood cell folate, and unmetabolized folic acid levels in each group following supplementation with (6S)-5-methyltetrahydrofolic acid or folic acid for 16-weeks of pregnancy.

Aim 2: To determine participation recruitment and retention rate, the most effective recruitment strategies for this population, and adherence to study protocol (to inform a definitive trial).

Exploratory Aims: To explore differences in proposed clinical effects associated with folic acid supplementatation (immunity, gene methylation) and differences in biomarkers that function closely with folate in one carbon metabolism (B-vitamins, choline and its metabolites [betaine, dimethylglycine]) and which support overall blood health (ferritin, inflammation). In the postpartum phase, we will quantify proportion of total breastmilk folate as folic acid in each group, evaluate correlation of maternal postpartum plasma unmetabolized folic acid and breastmilk folic acid, and to evaluate RBC folate concentrations following delivery in each group. Differences in breastmilk biomarkers associated with folate (choline, human milk oligosaccharides, and breastmilk microbiome) will be explored.

Women may undergo informed consent process anytime <21 weeks gestation. Once participants indicate that they are interested in participating in the trial, the participant will be given a study ID, and a baseline visit will be scheduled.

The baseline visit will occur between 8-21 weeks gestation, and will involve discontinuation of current folate/prenatal vitamin supplementation, review and signing the informed consent form (a scanned copy will be shared with the participant), randomization to a folate group, provision of study supplements, completion of a baseline questionnaire, completion of a food frequency questionnaire, measurement of weight and height, and a small blood draw (12ml).

Intervention: total time: 16 weeks. Participants will supplement daily with the folate and prenatal vitamin supplements. The research coordinator will call the participants half way through the intervention period to serve as a reminder and answer any questions, which will enhance protocol adherence.

The endline visit will occur between 24-37 weeks gestation, and will involve collecting any remaining supplements (for capsule counts), a weight measurement, and a small blood draw (12ml), and completion of a short endline questionnaire.

Optional continuation of study: After the endline visit, women who are planning to breastfeed will have the option to continue supplementing with the study supplements until approximately 1 week postpartum, at which time they will provide a small (3 mL) breastmilk sample and/or blood sample.

Study Type

Interventional

Enrollment (Actual)

60

Phase

  • Not Applicable

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

    • British Columbia
      • Vancouver, British Columbia, Canada, V6T 1Z4
        • University of British Columbia, Food Nutrition and Health Building

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

19 years to 42 years (Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Pregnant woman (singleton pregnancy)
  • Living in the Greater Vancouver area and willing to travel to the University of British Columbia for study visits
  • <21 weeks gestation
  • 19-42 years of age
  • willing to participate

Exclusion Criteria:

  • Have a pre-existing medical condition known to impact maternal folate status (malabsorptive of irritable bowel disease, active celiac disease, gastric bypass surgery, atrophic gastritis, epilepsy, advanced liver disease, kidney dialysis, type 1 or 2 diabetes mellitus, sickle cell trait/anemia)
  • Lifestyle factors known to impact maternal folate status (smoking, alcohol overuse, non-prescription drug use/abuse)
  • Are medium to high risk for development of an NTD-affected pregnancy (applies to women or their male partner: personal or family history [parents or siblings] of other folate sensitive congenital anomalies, personal NTD history or a previous NTD-affected pregnancy)
  • Are taking medications known to interfere with B-vitamin metabolism (Chloramphenicol, Methotrexate, Metformin, Sulfasalazine, Phenobarbital, Phenytoin, Primidone, Triamterene, Barbiturates)
  • pre-pregnancy body mass index ≥30 kg/m2
  • allergic to any of the supplement ingredients

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

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Folic acid
0.6 mg/day
Participants will supplement with 0.6mg/day for 16 weeks.
Experimental: (6S)-5-methyltetrahydrofolic acid (Metafolin)
0.625 mg/d (an equimolar dose to folic acid)
Participants will supplement with 0.625mg/day for 16 weeks.
Other Names:
  • Metafolin

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Concentration of red blood cell folate levels
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
nmol/L; Reflects longer term status (e.g. previous 3-4 months)
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
Concentration of serum folate levels
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
nmol/L; Reflects recent status or dietary intake
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
Concentration of unmetabolized folic acid (and other folate forms: THF, 5-Methyl-THF, 5-formyl-THF, and 5,10-methenyl-THF)
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
nmol/L; unmetabolized folic acid is not incorporated into RBCs, rather it circulates in plasma
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Concentration of total vitamin B-12
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
pmol/mL; closely involved in folate metabolism and facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of pyridoxal-5'-phosphate
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
nmol/L; closely involved in folate metabolism and facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of vitamin B2
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
nmol/L; closely involved in folate metabolism and facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of betaine
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
µmol/L; closely involved in facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of choline
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
µmol/L; closely involved in facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of dimethylglycine
Time Frame: concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
µmol/L; closely involved in facilitating methionine cycles
concentrations at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of S-adenosyl-methionine
Time Frame: concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
µM; Metabolite produced in methionine cycles
concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
Concentration of S-adenosyl-homocysteine
Time Frame: concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
µM; Metabolite produced in methionine cycles
concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
Concentration of total homocysteine
Time Frame: concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
µmol/L; Metabolite produced in methionine cycles
concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
Concentration of methionine
Time Frame: concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
µmol/L; Metabolite produced in methionine cycles
concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
Concentration of cysteine
Time Frame: concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
µmol/L; Metabolite produced in methionine cycles
concentrations at both baseline (8-21 weeks gestation) and endline (24-37 weeks gestation)
Collection of peripheral blood mononuclear layer cells
Time Frame: Collection at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Gene variant assessment of MTHFR (677 C>T, rs1801133, and 1298 A>C, rs1801131) and DHFR (rs1643649 and rs70991108) and differences in DNA methylation, and frequency and cytotoxicity of immune cells in PBMCs.
Collection at both baseline (8-21 weeks gestation), endline (24-37 weeks gestation)
Concentration of unmetabolized folic acid in breastmilk (and other folate forms: THF, 5-Methyl-THF, 5-formyl-THF, and 5,10-methenyl-THF)
Time Frame: Collection at 1 week postpartum
nmol/L; folic acid that is unmetabolized and enters breastmilk as such
Collection at 1 week postpartum
Folate binding protein in breastmilk
Time Frame: Collection at 1 week postpartum
nmol folate binding per liter of milk
Collection at 1 week postpartum
Breastmilk fatty acids & choline forms (free choline, betaine, phosphocholine, glycerophosophocholine)
Time Frame: Collection at 1 week postpartum
Quantified via LC-MS/MS
Collection at 1 week postpartum
Breastmilk human milk oligosaccharides and breastmilk microbiome
Time Frame: Collection at 1 week postpartum
Quantified via HPLC-FL and PCR
Collection at 1 week postpartum
Complete blood count
Time Frame: Baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
Analysis will be performed using an automated hematology analyzer (Sysmex XNL550, Kobe, Japan)
Baseline (8-21 weeks gestation), endline (24-37 weeks gestation), and postpartum
Markers of Iron and Inflammation
Time Frame: Baseline (8-21 weeks gestation),and endline (24-37 weeks gestation)
This will include measurement of serum ferritin (µg/L), soluble transferrin receptor (mg/L), body iron stores (mg/kg), retinol binding protein (µmol/L), CRP (mg/L), and AGP (g/L) in serum using a sandwich ELISA, and hormones that influence iron regulation in pregnancy, including serum hecipdin (ng/mL; measured with an ELISA) and serum erythropoietin (mIU/mL; measured with an immunoassay)
Baseline (8-21 weeks gestation),and endline (24-37 weeks gestation)

Collaborators and Investigators

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

Investigators

  • Principal Investigator: Crystal Karakochuk, PhD, University of British Columbia

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 (Actual)

September 16, 2019

Primary Completion (Actual)

September 8, 2021

Study Completion (Actual)

September 8, 2021

Study Registration Dates

First Submitted

July 14, 2019

First Submitted That Met QC Criteria

July 14, 2019

First Posted (Actual)

July 16, 2019

Study Record Updates

Last Update Posted (Actual)

April 14, 2023

Last Update Submitted That Met QC Criteria

April 11, 2023

Last Verified

April 1, 2023

More Information

Terms related to this study

Other Study ID Numbers

  • H18-02635

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

All of the individual participant data collected during the trial, after de-identification, will be available immediately following publication. Anyone who is interested in accessing the data should send a proposal to the principal investigator for approval to gain access.

IPD Sharing Time Frame

All data will be available following publication for approximately 5 years after initial collection.

IPD Sharing Access Criteria

A proposal from those interested in accessing the data should be sent to study investigators for access approval.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ICF
  • ANALYTIC_CODE
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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.

Clinical Trials on Pregnancy

Clinical Trials on Folic acid

Subscribe