NCT07346716

Medicines in Breast Milk and Estimated Infant Exposure

Medication Concentrations in Human Milk (MedMilk) and Potential Adverse Effects in Breastfed Infants: an Exploratory Clinical Study

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 250 (estimated)
• Sponsor: University Hospital Bispebjerg and Frederiksberg · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

The MedMilk (Medication concentrations in human Milk) study investigates how selected medicines taken by breastfeeding women are transferred into human milk and whether this may affect the breastfed child. The study includes breastfeeding women who are already using prescription or over-the-counter medicines as part of their usual care. Participants provide samples of breast milk and urine and complete a questionnaire about maternal and infant health. The collected data will be used to quantify medicine concentrations in milk and estimate the relative infant dose. The study aims to contribute new data to support safer prescribing and more informed counselling during breastfeeding

Detailed description

The MedMilk (Medication concentrations in human Milk) study is a prospective, exploratory clinical study coordinated by the Department of Clinical Pharmacology, Bispebjerg and Frederiksberg Hospital, Denmark. The study is observational in nature and involves no experimental drug administration. Participants are breastfeeding women using medicines as part of their routine treatment. Each participant will provide four small breast milk samples (1-20 mL each) collected at different time points in relation to maternal drug intake, one urine sample, and questionnaire data on maternal and infant health, breastfeeding patterns, and any infant symptoms potentially related to drug exposure. Samples are stored at -80 °C in a dedicated research biobank until analysis. Drug concentrations in milk and urine will primarily be quantified using solid Phase Extraction coupled with UPLC-MS/MS. Data will be analyzed descriptively, and relative infant doses (RID) will be calculated. For drugs with sufficient sampling density. Results will add to the limited body of systematic data on drug transfer into human milk and help inform clinical decision-making regarding medication use during breastfeeding.

Conditions

• Breastfeeding
• Medication Safety
• Lactation
• Drug Exposure Via Breast Milk
• Pharmacokinetic Parameters

Interventions

Type	Name	Description
DRUG	Prescription Drugs	Exposure to prescription medicines taken by breastfeeding women during routine treatment. The study does not assign medications but observes drug transfer into human milk from exposures occurring as part of usual care.

Timeline

• Start date: 2024-12-20
• Primary completion: 2028-01-01
• Completion: 2030-01-01
• First posted: 2026-01-16
• Last updated: 2026-01-16

Locations

3 sites across 1 country: Denmark