Pregnant women often experience preterm uterine contractions, but current methods of evaluation cannot quickly and accurately diagnose True Labor versus False Labor. Currently, these evaluations for “threatened labor” average 4 hours, and too frequently the resulting diagnosis is incorrect. Incorrect diagnoses lead to failure to administer therapies that prevent complications of prematurity or lead to lengthy, expensive and needless hospitalizations. Long evaluations create inefficiencies and delays starting proven therapies. Deliveries due to preterm labor are responsible for $10 B in annual healthcare costs in the US. Current methods produce many false positive and false negative diagnoses. Current methods diagnose True Labor in preterm patients with a sensitivity of only 40-60% and specificity of 60-85%. Each false negative result is a missed opportunity to treat with steroids before birth. Missing steroids increases the risk of lung and brain complications for premature babies. Each false positive is an inappropriate admission and treatment. The need to diagnose labor status more rapidly and accurately has been recognized for decades, but previous attempts have yielded only modest gains. PreTeL’s Labor Status Monitor provides major improvements using a revolutionary technological approach. This new approach arose from new knowledge of how the human uterus creates contractions, and then discovering how to determine if individual contractions are strong or weak. The core technology (uterine EMG) is well-established, but three key innovations are added. First, directional EMG sensors, called Area Sensors, are used to localize signals that originate on the uterine wall; Second, the local contractions are analyzed based on the degree of synchronization, or timing of the signals at different locations on the uterus; Third, Area Sensors revealed a unique EMG signal that occurs between contractions and characterizes False Labor. True versus False Labor is diagnosed based on two indices, one index for synchronization and the other for the False Labor signals. The Labor Status Monitor is designed to diagnose both True Labor and False Labor after only 1 hour of evaluation and with a higher sensitivity and specificity than current methods. In Aim 1 of this Phase II application, a clinical trial produces training data that identifies the thresholds of the two indices that optimize the diagnostic performance of the Labor Status Monitor. In Aim 2, indices are validated. Shortening the time needed for evaluation by 1 hour and improving sensitivity and specificity by 10% will reduce annual health care costs by $663 M. This proposal will provide data to fully plan the pivotal trial to support FDA approval.