Smart lactation pads can monitor safety of breast milk in real time

"Our device represents a major innovation," says first author Maral Mousavi, an assistant professor of biomedical engineering at USC. "It is the first wearable tool for direct biochemical analysis in breast milk and the first lactation pad embedded with real-time sensing technology. This technology has the potential to empower lactating individuals with actionable health insights, supporting both maternal and infant health in ways that have never before been possible."

To make the device, the researchers installed electrodes and tiny channels into a lactation pad -- an apparatus that nursing parents often wear throughout the day to protect their clothes from leaking breast milk. The smart lactation pad functions by measuring samples of the milk for acetaminophen as lactating parents go about their regular routines without requiring additional effort from the parent.

Since the smart pad continuously monitors levels of acetaminophen in the milk throughout the day, it also offers a tool for scientists to better understand how drugs are transferred into breast milk, says Mousavi.

"While it is generally safe at recommended doses, acetaminophen overexposure is a leading cause of acute liver failure in children," she says. "It remains the most common reason for liver transplants related to drug toxicity."

The researchers were inspired to build the lactation pad after a graduate student in their research group gave birth and was prescribed acetaminophen to manage her postpartum pain. Despite the importance of breast milk as a source of nutrition for infants and its ability to help their fragile immune systems develop, the team found that few technologies existed to monitor its safety in real time. While a few companies offer mail-in services, these services involve collecting samples in specialized kits that can be costly and waiting days or weeks for results.

"Given the risks and the critical decision-making parents face around breastfeeding and medication use, we wanted to create a tool that empowers them with real-time, personalized information rather than leaving them to rely on generalized drug-safety charts or delayed lab testing," says Mousavi.

The team hopes that the smart lactation pad can help parents make more informed decisions about breastfeeding after taking medications, such as optimizing the "pump and dump" strategy or discarding breast milk when drug levels are the highest.

In addition to painkillers, the authors note that new mothers are also commonly prescribed antibiotics or antifungals, and although these medications are generally considered safe to take while breastfeeding, they aren't always benign.

While the version of the smart pad described in this study was developed to measure acetaminophen, Mousavi says that it can be adapted to detect other drugs and biomarkers for assessing health. For example, Mousavi and colleagues recently demonstrated another lactation pad with an embedded sensor designed to monitor glucose levels in breast milk -- a function which she says could help parents manage their nutrition and address conditions such as gestational diabetes.

Currently, the device is only able to measure milk produced from natural leakage, meaning its applications may be limited when little leakage occurs. The pads are also disposable, so a new lactation pad is required for each new test. The researchers are currently working to develop a version of the device that analyzes pumped milk to offer a more accessible and convenient testing option for parents.