Non-invasive intrapartum fetal ECG: preliminary report.
OBJECTIVE
To obtain fetal heart rate, detailed fetal electrocardiography (fECG) signals and uterine contractions during labour using a single device.


METHODS
Prospective observational study.


METHODS
Delivery suite at a tertiary referral hospital, London, UK.


METHODS
Fifteen patients at median gestation of 39 weeks (range 24-41) were recruited at median cervical dilatation of 4.0 cm (range 0-10) of whom 8/15 (53%) had intact amniotic membranes.


METHODS
Using 12 abdominally sited electrodes, we recorded the composite abdominal signal in pregnancies intrapartum. The recorded data were analysed off-line using a blind signal separation technique.


METHODS
Success of signal separation and fECG time intervals.


RESULTS
Successful fECG signal acquisition was achieved in 12/15 (80%) patients and an averaged fECG waveform acquired. In these patients, P and QRS waves were seen in all cases, and T waves in 11/12 (92%). True beat-to-beat heart rate (HR) was displayed and measures of its variability obtained. The mother's ECG and uterine electrical activity, shown to match tocographically recorded uterine contractions, were also separated and displayed. Failure to acquire fECG in three cases was attributed to excessive abdominal muscular activity and electrical interference.


CONCLUSIONS
This study demonstrates a non-invasive technique that displays detailed intrapartum fECG waveforms, HR variability, maternal ECG and uterine contractions simultaneously, all in a single device and which avoids the potential risks of invasive monitoring with a fetal scalp electrode.
Taylor
Myles J O
MJ
Queen Charlotte's and Chelsea Hospital and Division of Paediatrics, Obstetrics and Gynaecology, Faculty of Medicine, Imperial College, London, UK.
Thomas
Matthew J
MJ
Smith
Mark J
MJ
Oseku-Afful
Salome
S
Fisk
Nicholas M
NM
Green
Andrew R
AR
Paterson-Brown
Sara
S
Gardiner
Helena M
HM
D015148:Cardiotocography / Q000295:instrumentation / Q000379:methods*; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005240:Feasibility Studies; D005260:Female; D006340:Heart Rate, Fetal / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D014590:Uterine Contraction / Q000502:physiology*