Quality Predictors of Abdominal Fetal Electrocardiography Recording in Antenatal Ambulatory and Bedside Settings

Abstract

Background: Fetal electrocardiography using an abdominal monitor (Monica AN24™) could increase the diagnostic use of fetal heart rate (fHR) variability measurements. However, signal quality may depend on factors such as maternal physical activity, posture, and bedside versus ambulatory setting. Methods: Sixty-three healthy women wore the monitor at home and 42 women during a hospital stay. All women underwent a posture experiment, and all home and 13 hospital participants wore the monitor during daytime and nighttime. The success rate (SR) of fHR detection was analyzed in relation to maternal physical activity, posture, daytime versus nighttime, and other maternal and fetal predictors. Results: Ambulatorily, the SR was 86.8% for nighttime and 40.2% for daytime. The low daytime SR was largely due to effects of maternal physical activity and posture. The in-hospital SR was lower during nighttime (71.1%) and similar during daytime (43.3%). SR was related to gestational age, but not affected by pre-pregnancy and current body mass index or fetal growth restriction. Conclusions: The success of beat-to-beat fHR detection strongly depends on the home/hospital setting and predictors such as time of recording, activity levels, and maternal posture. Its clinical utility may be limited in periods of unsupervised recording with physical activity or posture shifts.

Assessment of autonomic function in the late term fetus: The effects of sex and state

“…While patterns of accelerations and decelerations in fetal movement, heart rate and heart rate variability have been used to designate categories of fetal behavioral state, studies specifying these states in terms of quantified autonomic measures are rare. In addition, new technology has made possible the collection of true beat‐to‐beat tracings in the fetus (Huhn et al, ), an improvement over data typically derived from less precise Doppler measurements (Reinhard, Hatzmann, & Schiermeier, ) but which, up to this point has been used primarily for fetal monitoring in clinical settings (Crawford et al, ; Seliger et al, ).…”

A systematic scoping review to identify the design and assess the performance of devices for antenatal continuous fetal monitoring

“…Ten of the 43 studies were from the UK [25][26][27]35,[37][38][39]49,50,55], 22 from other European countries [24,[28][29][30][31][32][33]36,40,[42][43][44]48,[51][52][53][54]56,57,61,64,65], five from Japan [41,59,60,62,63], one from India [45], one from Australia [66], three from the United States of America (USA) [46,47,58], and one study from both the Netherlands and USA [34]. The included studies were heterogeneous, they had a median sample size of 34.5 participants (range 1-657) and a median number of recordings of 63 (range 1-657).…”

“…Thirty-five out of the 43 studies were specifically concerned with a device to measure the FHR. Twenty-nine studies utilised only fECG devices, of which nine were unnamed [24,25,27,30,31,40,44,49,55] and the remaining 20 studies used either: Monica AN24 device [26,33,34,36,38,39,[50][51][52]54,56,58]; Telefetalcare [28,29,53]; FECGV1 [35]; Cardiolab Babycard [43]; Nemo fetal monitor [48,57]; or Corometrics 112 abdominal ECG monitor [47]. Two studies used only fPCG devices, of which one was named the Fetaphon-2000 [42] and the other was unnamed [45].…”

“…A sub-group analysis was performed to look at the effect of converted data on heterogeneity, however no significant effect was seen (P = 0.093) between the studies with unconverted data (mean SQ 86%, 95% CI 79-94%) and those with converted data (mean SQ 59%, 95% CI 28-90%). The remaining four studies could not be included in the meta-analysis as they either did not provide an overall SQ [36,58] or they did not provide all of the required data (e.g. SD or IQR) [38,39].…”

“…The gestational age was broken down into distinct but unstandardized categories (e.g. 16 +0 to 19 +6 weeks' gestation) in ten of these studies [25,33,34,36,38,40,44,49,52,55], as shown in Fig 4. Overall, there was a reduction in the device performance in the middle gestational age categories, roughly from the start of the third trimester (28 +0 weeks) until 35-36 weeks' gestation. Moreover, the device performance was greatest at term or in post-term fetuses.…”