Flourish: Exploring the Early Infant Gut Microbiome

Summary

The goal of this clinical trial is to learn whether microbiome analysis, education, and personalized recommendations can improve gut health and reduce early markers of immune-related conditions in infants aged 0-3 months delivered via Cesarean section. The study aims to determine whether these interventions can increase beneficial bacteria, decrease C-section-associated microbiome signatures, reduce opportunistic pathogens, and improve functional potential for HMO digestion and SCFA production. The study also seeks to assess whether improvements in microbiome composition are associated with a reduced prevalence of early atopic symptoms.

Researchers will compare three groups: a full intervention arm that receives microbiome reports, coaching, personalized recommendations, and educational materials; a limited intervention arm that receives simplified reports and basic recommendations; and a control arm that receives no results until study completion. This design allows evaluation of both a comprehensive intervention and a more scalable, minimal-results model.

Participants will:

1. Provide six microbiome stool samples over a 24-month period.
2. Provide additional small stool samples at two timepoints for exploratory metabolomic analysis.
3. Receive microbiome reports and guidance according to their assigned study arm.
4. Complete surveys on infant health history, symptoms, diet, and environmental exposures.
5. Participate in standardized eczema assessment(s) administered by a Nurse Practitioner and evaluated by a Pediatric Allergy Specialist if any symptoms are reported.

This study seeks to demonstrate that targeted microbiome support can positively shift gut microbial development in C-section infants and may reduce risks linked to the early stages of the atopic march. Findings may inform scalable strategies for delivering microbiome-based support in early life and improve long-term health outcomes for this high-risk population.

Conditions

• Microbiota
• Gut Microbiome
• Eczema
• Microbiome

Interventions

DIETARY_SUPPLEMENT

Tailored Recommendations

Recommendations are tailored to the infant's microbiome composition, functional gene profiles (e.g., HMO digestion and SCFA production pathways), age, feeding method, and reported symptoms. Guidance may include evidence-based suggestions related to probiotic use, prebiotic intake, and age-appropriate nutritional strategies intended to support healthy gut microbiome development. All recommendations are educational in nature, optional, and provided for consideration by parents or caregivers. No supplements are provided directly as part of the study, and no supplementation is required for study participation. Recommendations are updated over time as new microbiome data are collected and are delivered according to study arm assignment. The full intervention arm receives comprehensive, personalized recommendations with interpretive support, while the limited intervention arm receives probiotic recommendations only designed to model a scalable laboratory-developed test (LDT)-style approach.

BEHAVIORAL

Consult Call

Participants assigned to the full intervention arm will receive scheduled consult calls with a trained microbiome specialist as part of the study intervention. These are conducted remotely and are designed to support participant understanding of microbiome reports, review educational content, and discuss microbiome-informed recommendations in the context of the infant's age, feeding practices, and reported symptoms. For participants in the full intervention arm, consult calls may include discussion of microbiome-guided recommendations related to diet, supplementation, and lifestyle factors. Participants in the limited intervention arm may elect to receive a call with a licensed Nurse Practitioner for the purpose of interpreting their static microbiome report only; these calls do not include personalized recommendations or discussion of broader health symptoms. Participants in the control arm do not receive consult calls during the active study period.

BEHAVIORAL

Educational Email Series

Participants assigned to the full intervention arm will receive a structured educational email series delivered longitudinally over the course of the study. The email series provides evidence-based education on early infant gut microbiome development and its relationship to immune and allergic health outcomes, with links to blog articles summarizing current peer-reviewed research. Topics include Cesarean delivery and microbiome seeding, breastfeeding and human milk oligosaccharides, formula selection, probiotic use, antibiotic exposure, gut maturation, introduction of solid foods and allergens, eczema and the atopic march, food sensitivities, environmental microbial exposure, and general strategies to support infant gut health during early life. The educational email series is informational only and does not include individualized medical advice. Participants in the limited intervention and control arms do not receive the educational email series during the active study period.

Sponsors & Collaborators

• Laboratory Corporation of America

  collaborator INDUSTRY

• Seeding Inc

  lead INDUSTRY

Principal Investigators

• Qian Yuan, MD · Massachusetts General Hospital

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

0 Months

Max Age

3 Months

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-01-31

Primary Completion

2028-06-30

Completion

2028-09-30

Countries

• United States

Study Locations