Scientists have developed a wearable ultrasound patch that can continuously monitor a baby’s health in the womb, offering the potential to detect complications that traditional prenatal scans may miss while reducing unnecessary hospital visits and easing pressure on healthcare systems.
The device, called UPatch, is a stick-on sensor designed to be worn for extended periods. It provides real-time imaging of the fetus and tracks blood flow, including in moving structures such as the umbilical cord. Researchers say it could bridge the gap between brief clinical scans and continuous monitoring systems that often produce excessive false alarms.
The technology was developed by a research team led by Professor Sheng Xu at Stanford University, in collaboration with scientists from Oxford University and the University of California, San Diego. The findings have been published in the journal Nature Biotechnology.
Current methods of fetal monitoring typically rely on occasional ultrasound scans during pregnancy or hospital-based systems that generate constant data but can be difficult to interpret due to frequent false alerts. UPatch is designed to offer a middle ground, delivering consistent monitoring over hours without requiring a specialist to be present.
In clinical trials involving 62 pregnant participants, the device’s readings closely matched those from standard handheld ultrasound equipment, suggesting it can reliably measure fetal blood flow over time.
Researchers also observed that fetal blood flow is not static, but fluctuates throughout the day. These temporary changes do not always indicate a medical problem, highlighting the importance of continuous observation rather than isolated snapshots.
In one case involving severe pre-eclampsia, the patch detected concerning changes in blood flow patterns. This prompted doctors to increase monitoring and ultimately proceed with a caesarean delivery four days later.
“This technology opens the possibility of monitoring fetal wellbeing continuously and non-invasively over much longer periods than is currently possible,” said Professor Antoniya Georgieva, one of the researchers involved in the study.
Other experts say the device could also reduce stress for expectant mothers. Researcher Mariana Tome noted that continuous monitoring could help women feel more reassured during pregnancy while also lowering the number of unnecessary scans, hospital visits and medical interventions.
First author Dr Tom Park highlighted its potential impact in regions with limited medical resources, where access to trained sonographers is scarce. He said the device could help improve prenatal care in healthcare “deserts” where delays in diagnosis are common.
While promising, UPatch is still at the proof-of-concept stage. The current version requires a wired setup and initial positioning using a conventional ultrasound scan. Researchers say larger trials across more diverse populations are still needed.
Future versions are expected to become fully wireless and more compact, raising the possibility that continuous fetal monitoring could eventually become part of everyday prenatal care rather than limited clinical appointments.
