(1154) Novel uEMG technology significantly improves preterm birth prediction: The Labor Status Monitor

Objective: Using current methods, sensitivity for predicting preterm birth (PTB) in patients presenting with contractions before 37 weeks GA is < 50%. While not all contractions contribute towards labor, legacy toco cannot distinguish those who will deliver preterm. We developed a novel Labor Status Monitor that uses uterine bioelectrical synchronization and between-contraction, tissue-level stimulation to predict PTB < 7 days.

Study Design: Multicenter, prospective cohort study of pregnant individuals between 26-36 weeks GA, with a cervix £ 5 cm and self-reporting ³ 1 contraction in 10 minutes (min). 6-channel uEMG recordings were obtained using PreTeL’s directional uEMG sensors applied to the abdomen for up to 4 hours (hr). uEMG data were classified on a channel-by-channel basis as rest, contraction-associated signals (CAS), or fasciculation-like signals (FLS, tissue-level stimulation between contractions). Contraction Synchronization Index (CSI) was calculated as CAS in > 5 channels observed over the previous 10-min, averaged over 60 min. FLS index (FLSi) was calculated as the fraction of time FLS occurred in each channel over the previous 10-min, averaged over all 6 channels, and then averaged over 1 hr. Primary outcome was delivery < 7 days of uEMG recording. Sensitivity and specificity were analyzed from receiver operator characteristic curves.

Results: 43 subjects were evaluated; 63% (27/43) delivered < 37 weeks GA, 34% (15/43) delivered < 7 days. AUC was 0.74 for CSI and 0.66 for FLSi for delivery < 7 days. Based on AUC, optimal sensitivities and specificities were 74% and 70% for CSI and 56% and 70% for FLSi. Assuming test independence, by applying CSI first, then applying FLSi to indeterminate results, sensitivity and specificity were 89% and 91% for delivery < 7 days.

Conclusion: Our analysis of the Labor Status Monitor suggests that uEMG significantly improves PTB prediction compared to current methods. Ability to predict PTB < 7 days has the potential to meaningfully impact management, particularly administration of antenatal corticosteroids. Further studies are needed to validate these findings.