Impact of GLP-1 RAs on Breastmilk Production and Nutritional Composition

This study focuses on the effects of a specific type of medication, known as GLP-1 Receptor Agonist (GLP-1 RA), on breastmilk production and nutrition in mothers after pregnancy. The interest in using GLP-1 RA medications post-pregnancy is growing, and this study aims to understand if these medications impact the quantity or quality of breastmilk. The study is particularly interested in exploring how weight loss induced by GLP-1 RA affects breastmilk production and its nutritional composition, including milk fat content. This research is important as it can provide valuable insights into the safety and effectiveness of GLP-1 RA medications for breastfeeding mothers. Participants in this study will be asked to weigh themselves daily and report their measurements. Over a period of approximately 2.5 to 4.5 months, they will attend 2-3 morning study visits, each lasting about 3 to 3.5 hours. During these visits, participants will use a provided breastpump to express milk for measurement of hourly milk production. They will also provide a small amount of milk for further analysis. The study will assess milk production rates before and after mothers start taking injected GLP-1 RA medications to reduce their body weight. Weight loss will be confirmed using 7-day body weight averages. The primary outcomes of the study include the hourly milk production rate and the milk's macronutrient composition, which will be evaluated using a standardized milk expression protocol and the Miris Human Milk Analyzer, respectively.