A feasibility study on non-invasive fetal ECG to evaluate prenatal autonomic nervous system activity

Assessment of human fetal cardiac autonomic nervous system development using color tissue Doppler imaging

“…FECG registration experiences frequent signal loss resulting in a low feasibility of 14%-63%, especially at early second trimester and between 28 and 34 weeks GA (0%-34%). 31,37 Although fMCG achieves a high feasibility at late second and third trimester (87%-100%), this technique encounters a poor signal-to-noise ratio in early stages. 38 Furthermore, the clinical relevance of fMCG is still debated as it remains too expensive and specialist-driven.…”

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].…”

“…above a certain level of quality [25,27,31,44,48,57]; traces with successful signal separation [55]; traces with successful estimation of the FHR [32,37]; or traces with successful measurement of the T/QRS ratio [30]. The success rates have a broad range (42.9-100%), and there is no obvious association between the year of the study and the success indicating no obvious improvement over time.…”

“…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.…”