Project Abstract Raydiant Oximetry, Inc. (Raydiant) has developed and patented a novel optical-sensing technology (‘LumerahTM’) to directly assess fetal status during labor and delivery through non-invasive, transabdominal measurement of fetal oxygenation. This technology will allow clinicians to directly monitor intrapartum fetal oxygenation. There are serious and significant limitations in the use of electronic fetal heart rate monitoring by cardiotocography (CTG) for monitoring fetal status during labor and detection of fetal compromise due to hypoxia. Owing to misinterpretation and inherent limitations of CTG, there is an intolerably high false positive rate (89%) for detecting fetal hypoxemia that has resulted in high rates of medically unnecessary cesarean deliveries. Cesarean delivery is not benign; it has potential adverse consequences for mothers and newborns and incurs substantial unnecessary healthcare cost. Furthermore, CTG false negatives, when fetal hypoxia is unrecognized owing to misinterpretation of CTG, result in devastating neonatal consequences, such as hypoxic ischemic encephalopathy that also incurs substantial healthcare cost. Monitoring fetal oxygenation in conjunction with CTG will provide a more precise modality of fetal surveillance during labor and delivery, safely reduce the use of medically unnecessary cesarean deliveries, and reduce the occurrence of newborns suffering consequences of metabolic acidosis In prior studies, supported by SBIR Phase I & II awards, Raydiant Oximetry: (i) developed computational models of fetal and maternal tissues in 2D and 3D to inform hardware design, algorithm development and feature set extraction; (ii) obtained first-in-human feasibility data in a clinical study of 6 pregnant women to validate the computational modeling efforts (clinicaltrials.gov: NCT04081623); and (iii) validated the approach with preclinical studies in the pregnant ewe model. The proposed Phase II SBIR builds directly upon these results. The goals of this research are to advance this technology towards commercialization by collecting human data training sets to refine the computational algorithm that allows separation of the fetal from maternal near infrared signals and then validate this algorithm to support an upcoming IDE filing with the FDA. This Phase II SBIR application is in response to the Notice of Special Interest (NOT-HD-21-053) from the NICHD to advance the development of non-invasive, physiological monitors that improve fetal assessment through the non- invasive measurement of fetal blood pH or oxygenation.