A team of researchers from Stanford University, the University of Oxford, and the University of California San Diego has developed a wearable ultrasound patch that could transform how clinicians monitor pregnancies. The device, known as UPatch, is a proof-of-concept stick-on sensor that can image a fetus and track blood flow in real time over several hours, including in moving structures such as the umbilical cord. The findings were published in Nature Biotechnology.
Current monitoring methods have significant gaps
Standard prenatal care across Europe and beyond relies on either occasional ultrasound scans—providing only brief snapshots of fetal health—or continuous monitoring that often generates so many false alarms that it becomes unreliable. UPatch aims to fill this middle ground by offering continuous, automatic tracking of blood flow and fetal wellbeing without requiring a specialist to be present.
In trials involving 62 pregnant participants, the device’s readings closely matched those from conventional handheld ultrasound, suggesting it can reliably monitor blood flow over extended periods. This could be particularly valuable in European regions where access to trained sonographers is limited, such as rural parts of the Balkans or remote areas in northern Scandinavia.
Clinical insights from continuous monitoring
The research also revealed that fetal blood flow can fluctuate dynamically over time, with temporary changes that may not indicate a persistent problem. In one severe case of pre-eclampsia, the patch detected worrying alterations in blood flow, prompting doctors to increase monitoring and perform a caesarean delivery four days later.
Professor Antoniya Georgieva, who contributed to the study, said: “This technology opens the possibility of monitoring fetal wellbeing continuously and non-invasively over much longer periods than is currently possible.”
Researcher Mariana Tome argued that the device could reshape the experience of pregnancy itself, “by helping women feel safer, more reassured and better supported throughout pregnancy, while also reducing unnecessary hospital visits, repeated scans and avoidable interventions.”
Potential for expanding access in underserved areas
First author Dr Tom Park highlighted the broader implications: “This technology could expand access to prenatal imaging in healthcare deserts and low-resource settings, where shortages of trained sonographers often delay care for high-risk pregnancies.” In Europe, such settings include parts of the continent where healthcare infrastructure is still developing, as well as migrant and refugee communities that often face barriers to consistent prenatal care.
The development of UPatch comes at a time when European health systems are increasingly looking for innovative ways to improve maternal and fetal outcomes while managing costs. For instance, renewable energy has already slashed electricity prices across the continent, and similar technological leaps in healthcare could yield comparable benefits.
However, UPatch remains a proof-of-concept. It currently relies on a wired backend setup and requires a conventional ultrasound scan to position it correctly. Further clinical trials on larger and more diverse populations are needed before it can be deployed in clinical settings across Europe and beyond.
