Impact of Vitamin D Supplements on Mental Health and Milk Composition in Mothers Living in Idaho

Effects of Maternal Stress on Human Milk Composition and Subsequent Infant Outcomes

Mothers of preterm infants experience exaggerated emotional stressors compared to those typically associated with new motherhood, making these women particularly vulnerable to postpartum depression. As many as 70% of mothers of preterm infants experience postpartum depression compared to only 12.5% of those delivering full-term infants. Increased stress and depression during this critical period are detrimental because they hamper a mother's ability to care for her infant and are associated with increased neonatal sepsis and mortality, decreased neonatal growth, and delayed motor and cognitive development. Postpartum depression is also associated with excessive maternal weight gain and risk for metabolic diseases, anxiety, and sleep disturbances. Stress in breastfeeding mothers can also alter circulating concentrations of some bioactive components (e.g., immunoglobulins, cortisol) that can transfer into milk. As such, understanding factors predisposing these vulnerable women to extreme levels of stress and finding ways to lower this stress and lessen its negative health outcomes on mothers and infants are important public health challenges. The March of Dimes estimates that 8.5% of births in Idaho are preterm, making this topic particularly relevant for Idaho women. Risk factors for postpartum depression in mothers delivering term or preterm infants are complex, but maternal nutrient deficiencies may be involved. Vitamin D status, for instance, is inversely correlated with risk of postpartum depression in women delivering term infants. However, vitamin D interventions have yielded inconsistent results, perhaps due to confounding impacts of geographic location, skin color, and endogenous vitamin D synthesis. Endogenous vitamin D synthesis requires cutaneous sunlight exposure, placing Idaho women at even greater risk of vitamin D deficiency - particularly in the winter when days are extremely short (only 7 hr on the winter solstice). The impact of maternal vitamin D supplementation during lactation on infant variables (e.g., vitamin D status) has been examined. However, its effect on maternal mental health has not been rigorously studied - let alone in the 'frontier and remote' (FAR) rural West, including Idaho, with short periods of wintertime sunlight and poor access to healthcare. Our long term goal is to develop interventions to improve maternal and infant health in Idaho - particularly in the context of preterm births. The overall primary objective of this proposal is to determine if maternal vitamin D supplementation improves vitamin D status and mental health in Idahoan mothers of preterm infants. Our central hypothesis is that vitamin D supplementation improves vitamin D status and reduces stress and other indicators of poor postpartum maternal mental health in Idaho women delivering preterm infants. Secondarily, we will assess the effects of maternal vitamin D supplementation on human milk composition.

Study Overview

• Status: Recruiting
• Conditions: Maternal Stress
• Intervention / Treatment: Other: Placebo; Dietary supplement: Vitamin D (Cholecalciferol )

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Idaho
    • Coeur d'Alene, Idaho, United States, 83814
      • Recruiting
      • Kootenai Health
      • Contact: Brook Lane, MD; Phone Number: 208-625-4000; Email: BLang@kh.org
      • Contact: Emily Kelley; Phone Number: 208-625-5275; Email: ekelley@kh.org
      • Sub-Investigator: Brook Lane
    • Moscow, Idaho, United States, 83844
      • Recruiting
      • University of Idaho
      • Contact: Yimin Chen, PhD, RDN; Phone Number: 208-885-6546; Email: yiminc@uidaho.edu
      • Contact: Sara Schumacher; Email: schu2500@vandals.uidaho.edu
      • Principal Investigator: Yimin Chen

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Mothers (>/= 18 years of age) of newborn infants (within first 4 months postpartum) in Idaho

Exclusion Criteria:

• Mothers (<18 years of age) of newborn infants (within first 4 months postpartum)
• Infants not anticipated to survive >72 hours

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Vitamin D	Dietary supplement: Vitamin D (Cholecalciferol ); 2,000 IU Vitamin D
Placebo Comparator: Placebo Control	Other: Placebo; Placebo

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maternal Vitamin D status	Blood vitamin D concentration	baseline, 4-week, 8-week
Maternal Stress	Maternal stress measured by the validated questionnaire: Perceived Stress Scale (PSS). The PSS can range from 0 to 40 with higher scores indicating higher perceived stress: 0-13 = low stress 14-26 = moderate stress 27-40 = high stress	baseline, 4-week, 8-week
Maternal Depression	Maternal depression measured using the validated questionnaire: Edinburgh Postnatal Depression Scale. The Edinburgh Postnatal Depression Scale can range from 0 to 30 with higher scores indicating higher depression. Any total score >10 indicates depression.	baseline, 4-week, 8-week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maternal Self-Compassion	Maternal self-compassion measured using the validated Self-Compassion-Short Form	8-week
Maternal physiologic stress	Blood and salivary cortisol	baseline, 4-week, 8-week
Physiologic Maternal Self-compassion	Blood oxytocin concentrations	baseline, 4-week, 8-week
Milk Immunomodulatory Composition	Milk Immunomodulatory protein concentrations	baseline, 4-week, 8-week

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maternal Diet	Diet assessed using 24-hour diet recall	baseline, 4-week, 8-week

Collaborators and Investigators

• Sponsor: University of Idaho
• Collaborators: National Institute of General Medical Sciences (NIGMS)

Study record dates

Study Major Dates

• Study Start (Actual): December 4, 2024
• Primary Completion (Estimated): May 31, 2027
• Study Completion (Estimated): May 31, 2027

Study Registration Dates

• First Submitted: April 2, 2025
• First Submitted That Met QC Criteria: April 2, 2025
• First Posted (Actual): April 9, 2025

Study Record Updates

• Last Update Posted (Actual): August 1, 2025
• Last Update Submitted That Met QC Criteria: July 31, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Calcium-Regulating Hormones and Agents; Physiological Effects of Drugs; Bone Density Conservation Agents; Micronutrients; Vitamins; Vitamin D; Cholecalciferol
• Other Study ID Numbers: IRB 20-024; P20GM152304 (U.S. NIH Grant/Contract)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No