Researchers at the University of Oxford have developed a wearable ultrasound patch that could allow doctors to continuously monitor a baby’s blood flow during pregnancy, potentially helping detect complications earlier and reduce the risk of stillbirth.
The study, published May 26 in Nature Biotechnology, was led by Professor Antoniya Georgieva of Oxford’s Nuffield Department of Women’s and Reproductive Health and founder of Safer Birth Ltd. Researchers said current pregnancy monitoring relies heavily on intermittent ultrasound scans and other tests that may miss critical changes between appointments, particularly in high-risk pregnancies.
The soft wearable device, known as the Ultrasound Patch or UPatch, is placed on the mother’s abdomen and continuously captures images of the baby’s anatomy and blood flow. Software automatically tracks blood vessels even as the mother and fetus move, reducing the need for a trained sonographer.
The technology was developed through a collaboration between Oxford researchers and engineers at the University of California San Diego and Stanford University. Professor Georgieva worked alongside Professor Sheng Xu, a specialist in soft electronics, and lead engineer Dr. Tom Park.
Researchers said the patch underwent 14 prototype versions before testing. Originally designed to monitor blood pressure in adult coma patients in intensive care units, the technology had to be adapted significantly for use in pregnancy because both the fetus and mother are constantly moving.
The device was tested in 62 pregnancies and showed strong agreement with standard clinical ultrasound systems commonly used in obstetric care. Researchers then conducted continuous monitoring sessions lasting between one and six hours in 52 pregnant women, including women with pre-eclampsia, gestational diabetes, hypertension and fetal growth restriction.
According to the study, the patch successfully detected changes in fetal blood flow associated with placental insufficiency and fetal distress. In one severe pre-eclampsia case, researchers said the patch identified abnormal blood-flow patterns that prompted closer monitoring and delivery by Caesarean section four days later.
Georgieva said the inability to reliably monitor babies in the womb remained a major gap in maternity care globally.
“The UPatch technology opens the possibility of monitoring the most important signals of fetal health over much longer periods,” she said in a statement. “This could ultimately help clinicians identify problems earlier.”
Xu said the project demonstrated how advances in electronics, ultrasound engineering and clinical science could address major unmet needs in pregnancy care.
Researchers said the technology could be especially useful in low-resource settings and healthcare deserts where shortages of trained sonographers delay care for high-risk pregnancies. Park said the device could expand access to prenatal imaging in underserved areas.
Mariana Tome, an obstetric doctor and co-author at Oxford’s Nuffield Department of Women’s and Reproductive Health, said the technology had the potential to reduce unnecessary hospital visits and repeated scans while helping women feel more reassured during pregnancy.
Researchers said the patch could eventually improve monitoring of pregnancies complicated by fetal growth restriction, hypertension and pre-eclampsia, conditions linked to placental dysfunction and reduced oxygen supply to the fetus.
The project was supported by the Wellcome Leap In Utero program, which funds technologies aimed at improving understanding of fetal development during pregnancy.
Although the current system still relies on wired electronics, researchers said future miniaturized versions could become fully wireless and easier to deploy in hospitals and community healthcare settings.
