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Clinical and Experimental Obstetrics & Gynecology  2020, Vol. 47 Issue (4): 459-464    DOI: 10.31083/j.ceog.2020.04.5422
Review | Next articles
Current methods of non-invasive fetal heart rate surveillance
A. Theodoridou1, *(), A. Athanasiadis2, G. Tsakmakidis2, Ι. Tsakiridis2, A. Pilavidi2, C. Vosnakis2, T. Dagklis2, G. Mavromatidis2, A. Mamopoulos2
1School of Health Sciences, Midwifery Department, International Hellenic University, Thessaloniki, Greece
2Third Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Abstract  

Introduction: As accurate fetal evaluation during labor is essential, there is a continuous need for better noninvasive ways of monitoring. Electronic fetal monitoring (EFM) is an essential tool towards effective fetal assessment during labor, with the invasive Intrapartum ST Segment Analyses (STAN) system an early favorite. There are very few non-invasive EFM devices worldwide, with only two having Food and Drug Administration (FDA) approval. Methodology: This state of the science review focuses on the most recent available scientific data regarding the role of non-invasive EFM and its effect on perinatal outcomes. Results: The Monica AN24 system, FDA approved and comparable to an external Doppler CTG, is independent of maternal BMI. The Mind child Meridian monitor, the second EFM device with FDA approval, is comparable to STAN, but with up to 32 electrodes for improved accuracy it can be difficult for medical professionals to master. The Nemo System, new to the market, was found to be highly acceptable as a 24-hour monitoring device by pregnant women in a single inaugural pilot study. Discussion: Non-invasive monitoring technology is making progress but there are still issues with signal acquisition and quality that stem from the newfound mobility of the monitored pregnant women. The two FDA approved devices are promising with a few caveats and there are also new devices that aim to improve on the shortcomings of the leaders with promising advances in signal acquisition and processing via additional electrodes and setups.

Key words:  Electrocardiography      Electrocardiotocography      Peripartum care      Cardiotocography     
Submitted:  09 November 2019      Accepted:  10 February 2020      Published:  15 August 2020     
*Corresponding Author(s):  A. Theodoridou     E-mail:  anattheo@midw.teithe.gr

Cite this article: 

A. Theodoridou, A. Athanasiadis, G. Tsakmakidis, Ι. Tsakiridis, A. Pilavidi, C. Vosnakis, T. Dagklis, G. Mavromatidis, A. Mamopoulos. Current methods of non-invasive fetal heart rate surveillance. Clinical and Experimental Obstetrics & Gynecology, 2020, 47(4): 459-464.

URL: 

https://ceog.imrpress.com/EN/10.31083/j.ceog.2020.04.5422     OR     https://ceog.imrpress.com/EN/Y2020/V47/I4/459

Table 1  — Pros and Cons of current fetal heart rate surveillance devices.
Method Main device Type Pros Cons
Cardiotocography Doppler
Ultrasound/toco dynamometer
I Most commonly used, Contraction monitoring, HR time series, Reduces incidence of fetal hypoxia [13] Expert user required, No real-time beat to beat data, Signal loss, (MHR)/(FHR) discrimination issues [1, 13-15]. Restricts mobility [14, 16]. Higher incidence of operative delivery [17, 18]
Magnetocardiography [19] Superconducting Quantum
Interference
Device (SQUID) sensors
NI. Multichannel, Good SNR for fetal signals, Good results [20] Expert user required. Specialist set up required. Short term monitoring only. Expensive, lack of mobility [21]
Electrode
electrocardiography
STAN monitor [27] I Very good FHR, Reduces neonatal metabolic acidosis, [4, 18, 28-31]. Reduces the need for blood sampling [40] Expert user required. Use only after the membranes have ruptured and cervical dilation has exceeded 2-3 cm [14, 18]
Latest meta-analysis has concluded that STAN does not have a place in modern obstetrics [4, 18]
MERIDIAN
Monitor* [23]
NI FDA approved for Weeks of Gestation (WOG) ≥ 36, Comparable to STAN [43] No skin preparation, Number of electrodes
[32] can be inconvenient for both staff and patient [42]
NEMO System [41] NI Highly accepted by patients [41]. Minor skin preparation, New to the market, 2 studies only [41, 44]
Non-invasive fetal electrocardiography FDA approved for WOG ≥ 36 weeks, Europe, WOG (≥ 20 weeks), Real-time FH, MHR EHG capable, Equal or even superiority in signal quality to the external Doppler, CTG independent of maternal BMI [54, 55] evaluate precise fetal cardiac time intervals (fCTIs) [57] Skin preparation required, Success of beat-to-beat fHR detection, dependant strongly on location, timing, maternal activity levels, and maternal posture. Might have limited clinical utility if it is unsupervised with physical activity or posture shifts [58].
MONIKA
AN24*/Novii

NI
KhAI-MEDICA [42] NI Only patent submitted N/A N/A
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