Ambulatory Fetal ECG Monitoring in High Risk Pregnancies (AMBER)

  • Research type

    Research Study

  • Full title

    Ambulatory Fetal ECG Monitoring in High Risk Pregnancies

  • IRAS ID

    260032

  • Contact name

    Basky Thilaganathan

  • Contact email

    baskaran.thilaganathan@stgeorges.nhs.uk

  • Sponsor organisation

    Biorithm

  • Duration of Study in the UK

    0 years, 3 months, 1 days

  • Research summary

    Research Summary

    The purpose of this clinical investigation is to assess the accuracy of femom, a novel fetal heart rate monitoring device. femom utilises novel technology to interpret fetal heart rate patterns when applied abdominally. The output of the device (Fetal Heart Rate, Maternal Heart Rate and Uterine Activity) mirrors that of the cardiotocogram (CTG) which is the current standard of care for in-hospital monitoring of fetal heart rate, both antenatally and in the intrapartum period. By virtue of femom’s design, the device aims to allow for ambulatory monitoring of pregnant women both within and outside the healthcare facility setting.
    This clinical investigation is designed to achieve the following aims:

    i) Examine the similarity between fetal heart rate (FHR), maternal heart rate (MHR) and uterine activity (UA) measured by femom vs cCTG
    ii) Assess whether there are any differences in fetal heart rate short-term variation (STV) measured by femom vs cCTG
    iii) Elicit patient opinion on the utilisation of femom (i.e. What do patients think?)
    iv) Elicit clinician opinion on the utilisation of femom (i.e. What do clinicians think?)
    v) Examine the signal loss seen in femom vs cCTG

    Summary of Results

    The objective of AMBER 1 was to establish the feasibility of a novel fetal heart rate (FHR) monitor (Femom), which may enable women to monitor their babies in the comfort of their own homes. This monitor can be self-applied by women without medical assistance, and can collect important information regarding FHR fluctuations, which are important markers of the baby’s wellbeing. These FHR fluctuations are known as short-term variation (STV), and phase-rectified signal averaging (PRSA), which further includes 2 components, namely accelerative and decelerative capacities (AC and DC). In this study we compared Femom with the current gold standard - computerised cardiotocography (cCTG), for the measurement of these parameters.

    The study took place in a large London Hospital. Pregnant women with a singleton baby over 28 weeks gestation who required cCTG monitoring were invited to take part. After written consent, they underwent Femom monitoring at the same time as their routine cCTG for up to 60 minutes. Signal loss, FHR and its fluctuations were analysed for Femom, and compared with the same parameters from the cCTG.

    306 FHR monitoring sessions (traces) were obtained from 285 women. From the recordings which were interpretable, there was little difference between FHR monitored between the two devices. Signal loss was higher in Femom than cCTG (17% vs 1%). Signal loss was increased earlier in pregnancy in both monitors. Signal loss from Femom was not affected by maternal weight or a very active baby, unlike that from the cCTG. The FHR fluctuation parameters - STV and PRSA generated by Femom were highly correlated to those from the cCTG when the traces were fully filtered. However, this excluded many traces due to signal loss. Removing the filters produced more results, but meant that the values were no longer highly correlated. Correcting this with algorithms meant we produced good correlation between Femom and cCTG parameters, with higher outputs and less signal loss. Using this data, we were able to produce automated reporting criteria for home FHR monitoring.

    Participant feedback surveys showed high satisfaction levels for the women who took part in the study, with 86% of women choosing Femom as a preferred method of monitoring in the future. Importantly, no safety issues were reported for mothers or babies in the conduct of this study, however, one woman reported a self-limiting rash due to the stickers used in Femom, which resolved the following day.

    Amber 1 Has shown that Femom is able to produce FHR and variability parameters which are comparable to cCTG. This is done through appropriate signal processing with algorithms. Future research is needed to explore the safety and reliability of home FHR monitoring.

  • REC name

    South East Scotland REC 02

  • REC reference

    19/SS/0109

  • Date of REC Opinion

    4 Nov 2019

  • REC opinion

    Further Information Favourable Opinion