ECG Biosensors

The Frasch Lab develops non-invasive fetal ECG monitoring approaches to identify fetuses developing acidemia using heart rate variability (HRV) analysis with FDA-approved transabdominal fetal ECG monitors.

Research Focus

Fetal Monitoring Applications

• Non-invasive identification of fetuses developing acidemia using multidimensional fetal HRV analyses
• Detection of systemic and gut fetal inflammatory response in fetal sheep models
• Identification of chronic stress exposure during pregnancy, Zika virus exposure, and autism spectrum disorder

Theoretical Contributions

We investigate the origins of fetal HRV in the stochastic fluctuations of cardiac sinus node cells’ ion channels as a foundation for understanding the memory of chronic hypoxia in HRV patterns.

The HRV Code

We conceptualize an “HRV code” framework synthesizing findings across species and conditions to develop generalized understanding of heart rate variability beyond fetal applications.

Selected Publications

From the Frasch Lab

• Measuring the time-scale-dependent information flow between maternal and fetal heartbeats during the third trimester — Biology, 2026
• Advancements in fetal heart rate monitoring: opportunities and strategic initiatives for better intrapartum care — BJOG, 2025
• Monitoring chaos at the cot-side — Pediatric Research, 2024
• Heart rate variability code: does it exist and can we hack it? — Bioengineering, 2023
• Fetal heart rate variability: an ocean of meanings beyond ups and downs — BJOG, 2023
• When is a potential new screening algorithm ready for translation? — Pediatric Research, 2023
• Editorial: Fetal-maternal monitoring in the age of artificial intelligence and computer-aided decision support — Frontiers in Pediatrics, 2022
• A novel method for the extraction of fetal ECG signals from wearable devices — IEEE EMBC, 2022
• Comprehensive HRV estimation pipeline in Python using Neurokit2: application to sleep physiology — MethodsX, 2022
• Sampling rate and heart rate variability: on metrics and health outcomes — Journal of Biomedical Informatics, 2022
• Detection of maternal and fetal stress from the ECG with self-supervised representation learning — Scientific Reports, 2021
• Detection of preventable fetal distress during labor from scanned cardiotocogram tracings using deep learning — Frontiers in Pediatrics, 2021
• Relationship between deceleration morphology and phase-rectified signal averaging-based parameters during labor — Frontiers in Medicine, 2021
• Fetal cardiovascular decompensation during labor predicted from the individual heart rate tracing: a machine learning approach in near-term fetal sheep — Frontiers in Pediatrics, 2021
• Machine learning model on heart rate variability metrics identifies asymptomatic toddlers exposed to Zika virus during pregnancy — Physiological Measurement, 2021
• Can a composite heart rate variability biomarker shed new insights about autism spectrum disorder in school-aged children? — Journal of Autism and Developmental Disorders, 2021
• Neonatal sepsis is diminished by cervical vagus nerve stimulation and tracked non-invasively by ECG — arXiv preprint, 2020
• Fetus: the radar of maternal stress — a cohort study — arXiv preprint, 2019
• Vagal contributions to fetal heart rate variability: an omics approach — arXiv preprint, 2019
• Fetal-maternal ECG analysis — bioRxiv preprint, 2018
• Non-invasive acquisition of fetal ECG from the maternal xyphoid process: a feasibility study in pregnant sheep — arXiv preprint, 2017
• Stochastic properties of fetal heart rate — Frontiers in Physiology, 2017
• Clinical trial: Fetal acidemia detection at the bedside — ClinicalTrials.gov, 2017
• Fetal ECG dataset — Harvard Dataverse
• Neuroinflammation and vagus nerve activity — Frasch et al., Journal of Neuroinflammation, 2016
• Fetal ECG signal processing and analysis — PLoS One, 2016
• Monitoring fetal intestinal inflammation using HRV — Liu et al., Pediatric Critical Care Medicine, 2016
• Sampling rate effects on fetal HRV metrics — Durosier et al., Physiological Measurement, 2015
• Fetal HRV analysis for acidemia detection — Physiological Measurement, 2014

Supporting Research from the Field

• Predicting the risk of sudden cardiac death — Lerma & Glass, J Physiol, 2016
• A comparison of single channel fetal ECG extraction methods — Behar, Johnson, Clifford & Oster, Ann Biomed Eng, 2014
• Noninvasive fetal ECG: the PhysioNet/Computing in Cardiology Challenge 2013 — Silva, Behar, Sameni, Zhu, Oster, Clifford & Moody, Comput Cardiol, 2013
• A review of fetal ECG signal processing; issues and promising directions — Sameni & Clifford, Open Pacing Electrophysiol Ther J, 2010