NCT07467694

Brief Summary

The purpose of this study is to learn how exercise and physical activity during pregnancy and after pregnancy may affect the composition of breastmilk. Certain changes in breast milk after exercise may have an impact on how infants use energy. Understanding this process may improve public health recommendations for exercise during and after pregnancy. This study can help investigators learn more about how maternal exercise patterns may affect body growth and obesity risk in infants who are breastfed. This research may help identify how different factors can influence healthy weight and early development in infants.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
200

participants targeted

Target at P75+ for not_applicable

Timeline
48mo left

Started Dec 2025

Longer than P75 for not_applicable

Geographic Reach
1 country

2 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress15%
Dec 2025Jul 2030

Study Start

First participant enrolled

December 1, 2025

Completed
3 months until next milestone

First Submitted

Initial submission to the registry

February 17, 2026

Completed
23 days until next milestone

First Posted

Study publicly available on registry

March 12, 2026

Completed
4.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 1, 2030

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

July 1, 2030

Last Updated

March 12, 2026

Status Verified

March 1, 2026

Enrollment Period

4.6 years

First QC Date

February 17, 2026

Last Update Submit

March 11, 2026

Conditions

Childhood Obesity PreventionChildhood ObesityPhysical ActivityLactationBreastfeedingPregnancyExercise

Keywords

LactationBreastfeedingBreast milkPregnancyExercise

Outcome Measures

Primary Outcomes (2)

  • Altered breast milk lipidome

    Milk composition measured through lipidomics

    8 weeks

  • Altered breast milk metabolome

    Human milk composition measured via metabolomics

    8 weeks

Secondary Outcomes (3)

  • Infant body composition

    3 months, 6 months, and 12 months

  • Infant body mass index (BMI)

    3 months, 6 months, and 12 months

  • Infant resting metabolic rate

    3 months of age

Other Outcomes (2)

  • Infant brown adipose tissue anatomy

    2 months

  • Heat production

    1 month and 3 months

Study Arms (2)

Enhanced physical activity

EXPERIMENTAL

Participants in this group will be encouraged to engage in daily physical activity

Behavioral: Active group

Control group

NO INTERVENTION

Usual care

Interventions

Active groupBEHAVIORAL

For participants randomized to the Active group, there will be weekly phone calls with study staff during which step counts and exercise bouts from the previous week will be reviewed, and exercise goals for the following week will be gradually increased.

Enhanced physical activity

Eligibility Criteria

Age18 Years - 45 Years
Sexfemale
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • y of age at the time of enrollment
  • Pre-gravid or first trimester BMI 18.5 -40 kg/m2
  • Uncomplicated singleton pregnancy
  • Intention to exclusively breastfeed for \>3 months and, if parity \>1, that they successfully breastfed a previous pregnancy
  • Term pregnancy (gestational age 37 to \<42 weeks)
  • Infant with birth weight \>10th percentile of weight for gestational age

You may not qualify if:

  • Any obstetric contra-indication to exercise at 1 month
  • Diagnosis of uncontrolled (HbA1c \>7%) type 1 or type 2 diabetes, or gestational diabetes managed with insulin
  • Intrauterine growth restriction
  • Pre-eclampsia or other pregnancy complications
  • Alcohol, cannabis or tobacco use
  • Known congenital metabolic, endocrine disease, or congenital illness affecting infant feeding/growth
  • Major fetal anomalies
  • Musculoskeletal issues that would make exercise difficult

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

Joslin Diabetes Center

Boston, Massachusetts, 02215, United States

RECRUITING

Oklahoma University College of Medicine

Oklahoma City, Oklahoma, 73104, United States

RECRUITING

MeSH Terms

Conditions

Pediatric ObesityMotor ActivityBreast Feeding

Condition Hierarchy (Ancestors)

ObesityOverweightOvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and SymptomsBehaviorFeeding Behavior

Central Study Contacts

Elvira M Isganaitis, MD, MPH

CONTACT

617-309-4554elvira.isganaitis@joslin.harvard.edu

Study Coordinator

CONTACT

857-289-3455PeaBaBy@joslin.harvard.edu

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
SINGLE
Who Masked
OUTCOMES ASSESSOR
Purpose
PREVENTION
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 17, 2026

First Posted

March 12, 2026

Study Start

December 1, 2025

Primary Completion (Estimated)

July 1, 2030

Study Completion (Estimated)

July 1, 2030

Last Updated

March 12, 2026

Record last verified: 2026-03

Locations

US(2)