A Phase 1/2 interventional study of 5-MTHF Supplementation and Placebo in Breastfeeding, sponsored by Fundació Sant Joan de Déu. Not yet recruiting at 2 sites in Spain. Open to female participants aged 18 Years to 42 Years. Per ClinicalTrials.gov, last updated 2026-04-02.
Sponsored by Fundació Sant Joan de Déu · Phase 1/2, Interventional, and Basic science
This double-blind, randomized, placebo-controlled parallel trial evaluates the effects of maternal 5-methyltetrahydrofolate (5-MTHF) supplementation during breastfeeding. Thirty-six lactating mother-infant dyads will be randomized (1:1) to receive 5-MTHF or placebo for 6 weeks, stratified by infant sex and mode of delivery. Tolerability and adverse events will be monitored.
Pre- and post-intervention assessments include breast milk one-carbon metabolites and oligosaccharides; maternal plasma one-carbon metabolites and metabolic health markers. Maternal mental health will be evaluated using the SCL-90-R questionnaire. A follow-up visit at 4 months will reassess infant anthropometry and microbiome outcomes.
1,081 studies on the registry are indexed under Breast Feeding; 217 are open to participants now.
This study's planned enrollment of 36 is below the median of 100 across 844 interventional studies indexed under Breast Feeding.
Browse Breast Feeding studies →Fundació Sant Joan de Déu is the lead sponsor of 70 studies on the registry; 19 are open to participants now.
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Exclusion Criteria:
Dietary Supplement (5-MTHF)
Dietary Supplement: 5-MTHF Supplementation
Placebo
Other: Placebo
Oral supplementation with 5-MTHF (800 µg) administered daily for 6 weeks during lactation.
Matching placebo administered daily for 6 weeks during lactation.
Incidence of Adverse Events
Treatment safety and tolerability will be evaluated by assessing differences in the incidence of potential adverse events between groups, focusing on gastrointestinal symptoms.
Time frame: Baseline, 6 weeks, 4 months
Change in breast milk 5-MTHF concentration
Change in breast milk 5-MTHF concentration measured with liquid chromatography coupled to mass spectrometry (LC-MS) from Baseline to 6 weeks.
Time frame: Baseline, 6 weeks
Change in plasma 5-MTHF concentration
Change in maternal plasma 5-MTHF concentration measured with liquid chromatography coupled to mass spectrometry (LC-MS) from Baseline to 6 weeks.
Time frame: Baseline, 6 weeks
Change in breast milk one-carbon metabolite concentration
Change in breast milk one-carbon-related metabolites (choline, methionine, SAM, SAH, homocysteine, cystathionine, folic acid, betaine) from Baseline to 6 weeks.
Time frame: Baseline, 6 weeks
Change in plasma one-carbon metabolite concentration
Change in plasma one-carbon-related metabolites (choline, methionine, SAM, SAH, homocysteine, cystathionine, folic acid, betaine) from Baseline to 6 weeks.
Time frame: Baseline, 6 weeks
Change in Human Milk Oligosaccharide (HMO) concentration
Change in HMO concentrations between Baseline and 6 weeks
Time frame: Baseline, 6 weeks
Change in Maternal Plasma Glucose Concentration
Change in maternal blood glucose levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Plasma Glycated Hemoglobin (HbA1c) Concentration
Change in maternal blood glycated hemoglobin (HbA1c) between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Plasma Insulin Concentration
Change in maternal blood insulin levels between Baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Plasma Triglyceride (TAG) Concentration
Change in maternal blood triglyceride (TAG) levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood Total Cholesterol Concentration
Change in maternal blood total Cholesterol levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood LDL Cholesterol Concentration
Change in maternal low-density lipoprotein (LDL) cholesterol levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood HDL Cholesterol Concentration
Change in maternal high-density lipoprotein (HDL) cholesterol levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood Alanine Aminotransferase (ALT) Levels
Change in maternal alanine aminotransferase (ALT) levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood Aspartate Aminotransferase (AST) Levels
Change in maternal aspartate aminotransferase (AST) levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Maternal Blood Gamma-Glutamyl Transferase (GGT) Levels
Change in maternal gamma-glutamyl transferase (GGT) levels between baseline and 6 weeks.
Time frame: Baseline, 6 weeks
Change in Symptom Checklist-90-Revised (SCL-90-R) scale
The SCL-90-R is a 90-item self-report questionnaire assessing psychological symptoms over the past week, with a range of 0-90 across 9 dimenions: Somatization, Obsessive-compulsive, Interpersonal sensitivity, Depression, Anxiety, Hostility, Phobic anxiety, Paranoid ideation, Psychoticism. Higher scores indicate worse outcome.
Time frame: Baseline, 3 weeks
Change in infant BMI z-score
We will measure infant body weight, length, and head circumference to calculate BMI z-scores according to WHO growth standards, and changes between baseline, 6 weeks and 4 months will be assessed.
Time frame: Baseline, 6 weeks
Maternal and infant gut microbiome composition
Bacterial DNA will be isolated from infant and maternal fecal samples and sequenced to obtain microbiome composition.
Time frame: Baseline, 6 weeks
Maternal plasma and breast milk metabolomic profile
The metabolomic profile will be obtained with the Biocrates Quant 1000 kit from plasma and breast milk samples.
Time frame: Baselina, 6 weeks
Milk imprinted protein levels
Imprinted proteins in human milk samples will be analyzed by ELISA.
Time frame: Baseline, 6 weeks
Plan to share: Undecided
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Fundació Sant Joan de Déu