# Development of low-cost optically pumped magnetometer system for fetal applications

> **NIH NIH R01** · UNIV OF ARKANSAS FOR MED SCIS · 2023 · $372,980

## Abstract

Abstract
Currently, we can record non-invasive fetal magnetocardiographic (FMCG) signals with a magnetic sensor-
based system called SARA (SQUID Array for Reproductive Assessment) installed at University of Arkansas for
Medical Sciences. The study of the fetal heart, and in particular, the developing cardiac conduction system, has
been significantly aided in the last two decades by the introduction of FMCG. The American Heart Association
recently acknowledged the academic and clinic usefulness of this new modality. Several studies have shown
that FMCG can provide new relevant clinical parameters for assessment of fetal cardiac activity and also
supplement the parameters that are currently available. Despite all these benefits, the major hurdles facing
SQUID technology include system and maintenance cost, cryogenic helium cooling, a rigid one-size-fits-all array,
and a single position option for the mother. We have shown the feasibility of using uncooled biomagnetometer
for potential prenatal assessments based on microfabricated optically-pumped magnetometers (OPM). The
OPMs have many features similar to cryogenic SQUID-based systems as they measure the same field
components, and are compatible with standard magnetically-shielded rooms. This proposal is in response to
NIBIB’s PAR-19-158 Bioengineering Research Grants, where we apply a multidisciplinary integrative team
approach to we plan to design, test and validate a 24-channel OPM sensor system that fits over the maternal
abdomen. Performance of the OPM in a three-layered shielded room will be evaluated with respect to the data
quality of FMCG signals which will be compared to those obtained from a gold standard SQUID based system.
The overall goal is to demonstrate that with OPM systems (a) we can design a stand-alone flexible array for
maternal-fetal application (b) record the desired biomagnetic signals equivalent to SQUID sensors; (c) be able
to separate the signal into their constituents to extract FMCG and (d) quantify fetal heart signals and the relevant
metrics. We believe that with potential lower costs and maintenance requirements, the benefits of using fetal
biomagnetometery could be translated from the research to possible widespread clinical applications.
The specific aims are as follows:
Aim 1: Design and configure a bed-based stand-alone array of OPMs that conforms to the shape of the
maternal abdomen in order to obtain signals with sufficient signal-to-noise ratio for fetal applications.
Aim 2: Extract and quantify the FMCG waveform components to compute a) PQRS and T wave detection
rates and cardiac time intervals (CTI).
Aim 3: Record and characterize FMCG of fetuses that have been referred with abnormal heart conditions
detected through routine ultrasound examination.

## Key facts

- **NIH application ID:** 10589808
- **Project number:** 5R01HL164303-02
- **Recipient organization:** UNIV OF ARKANSAS FOR MED SCIS
- **Principal Investigator:** Hari Eswaran
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2023
- **Award amount:** $372,980
- **Award type:** 5
- **Project period:** 2022-03-15 → 2026-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10589808

## Citation

> US National Institutes of Health, RePORTER application 10589808, Development of low-cost optically pumped magnetometer system for fetal applications (5R01HL164303-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10589808. Licensed CC0.

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