Exercise after pregnancy to activate infant brown fat
Impact of Acute Exercise and Habitual Physical Activity on Human Milk Composition and Childhood Obesity Risk
This study will test if a mother's exercise during pregnancy and after birth changes her breast milk so it increases her infant's brown fat activity and energy use.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 200 (estimated) |
| Ages | 18 Years to 45 Years |
| Sex | Female |
| Sponsor | Joslin Diabetes Center Academic / other |
| Locations | 2 sites (Boston, Massachusetts and 1 other locations) |
| Trial ID | NCT07467694 on ClinicalTrials.gov |
What this trial studies
Investigators will measure habitual maternal activity during pregnancy and postpartum, perform supervised acute moderate exercise bouts, and collect breast milk for metabolite and lipid analysis. They will measure infant growth, body composition, and energy expenditure to see whether exercise-related changes in milk correlate with increased brown fat activity. The central idea is that exercise-induced changes in milk could raise infant energy use and lower later obesity risk. This multi-site study includes in-person testing visits and laboratory analyses of milk and infant metabolic outcomes.
Who should consider this trial
Good fit: Ideal candidates are pregnant people aged 18–45 with pre-pregnancy BMI 18.5–40 kg/m2 carrying an uncomplicated singleton pregnancy who plan to exclusively breastfeed for at least three months and deliver a term infant.
Not a fit: People with uncontrolled diabetes, pregnancy complications, substance use, major fetal anomalies, infants born preterm or small for gestational age, or those unable to exercise are unlikely to benefit or be eligible.
Why it matters
Potential benefit: If successful, the results could identify exercise recommendations for mothers that change breast milk in ways that help infants burn more energy and reduce obesity risk.
How similar studies have performed: Prior research shows maternal factors like BMI and activity affect milk composition and breastfeeding is linked to lower obesity risk, but direct evidence that maternal exercise changes milk to activate infant brown fat is limited and relatively novel.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * 18-45 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 Exclusion Criteria: * 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
Where this trial is running
Boston, Massachusetts and 1 other locations
- Joslin Diabetes Center — Boston, Massachusetts, United States (Recruiting)
- Oklahoma University College of Medicine — Oklahoma City, Oklahoma, United States (Recruiting)
Study contacts
- Study coordinator: Elvira M Isganaitis, MD, MPH
- Email: elvira.isganaitis@joslin.harvard.edu
- Phone: 617-309-4554
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.