Transabdominal Measurement of Fetal Oxygen Saturation and Blood Flow Index through Multi-exposure Time-of-flight Filtered Interferometric Diffusing-wave Spectroscopy

Abstract

Researchers at the University of California, Davis have developed a noninvasive optical technology that simultaneously measures fetal oxygen saturation and blood flow during labor through advanced interferometric spectroscopy.

Full Description

This technology employs multi-exposure time-of-flight filtered interferometric diffusing-wave spectroscopy (multi-exposure TOF-iDWS) using laser light split between a reference and sample arm to noninvasively probe the maternal abdomen. By rapidly sweeping laser wavelengths and controlling optical path differences, it selectively detects light signals from both maternal superficial tissue and deeper fetal tissue. Varying camera exposure times and computational algorithms enable extraction of both blood flow index and oxygen saturation for mother and fetus with enhanced signal fidelity. The system can be realized with fiber optics, free-space optics, or a hybrid, using a variety of light delivery and collection methods.

Applications

• Monitoring of fetal oxygen saturation and blood flow during labor and delivery. 
• Assessment tool to decide on cesarean section or instrumental vaginal delivery. 
• Noninvasive fetal health evaluation in prenatal care centers and hospitals. 
• Potential expansion into monitoring oxygenation and blood flow in other deep multilayer tissues such as the brain. 
• Medical devices integrating optical sensing for maternal-fetal health management.

Features/Benefits

• High collection throughput enabling detection of weak fetal signals. 
• Time-of-flight filtering to selectively isolate deep fetal tissue signals and suppress maternal interference. 
• Simultaneous measurement of fetal blood flow index and oxygen saturation during labor. 
• Enhanced signal-to-noise ratio and robustness against noise via multi-exposure strategy. 
• Non-invasive and real-time monitoring suitable for intrapartum fetal health assessment. 
• Flexible optical system implementations (fiber optics, free-space, hybrid). 
• Overcomes poor signal quality and low fetal signal penetration common in existing fetal pulse oximetry. 
• Separates weak fetal signals from dominant maternal tissue signals noninvasively. 
• Addresses safety concerns by improving signal collection without increasing illumination intensity. 
• Provides a combined blood flow and oxygen saturation metric, which was previously unavailable in optical fetal monitoring.

Patent Status

Patent Pending