Study of Injectable GLP-1 Receptor Agonists and Their Effects on Breastfeeding and Milk Nutrition in Mothers Using These Medications for Weight Loss

What this Trial Is About

Researchers are studying breastfeeding mothers who are prescribed injectable GLP-1 Receptor Agonist GLP-1 RA medications to reduce body weight after pregnancy. The study aims to understand if these medications affect breastmilk production or change the nutritional content of the milk, including fat levels. It focuses on mothers eligible for GLP-1 RA treatment with specific body mass index BMI and related health conditions. Participants will be observed before and after they begin their prescribed GLP-1 RA injections, such as semaglutide or tirzepatide, which are part of their clinical care but not provided by the study. They will use a study-provided breastpump during visits to express milk multiple times for measurement, and researchers will monitor changes in milk production and composition over up to two months after starting treatment. If medication dosage increases, the observation period restarts. During the study, mothers will weigh themselves daily and report these measurements. They will attend 2 to 3 morning visits lasting approximately 3 to 3.5 hours each over 2.5 to 4.5 months. At each visit, breastfeeding patterns will be recorded, milk samples collected, and milk production rates measured. Researchers will track changes in hourly milk production and milk macronutrient content to evaluate the effects of GLP-1 RA treatment on lactation.

Effects of GLP-1 RAs on Human Lactation Outcomes