Fetal electrocardiogram (ECG) for fetal monitoring during labour

The use of adjunctive ST waveform analysis (STAN) during continuous electronic fetal heart rate monitoring in labour may result in fewer operative vaginal deliveries compared to continuous electronic fetal heart rate monitoring alone, but there is insufficient evidence for patient-important outcomes.

A Cochrane review included 7 studies with a total of 27 403 women (6 studies were based on ST analysis and 1 on PR length). In comparison to continuous electronic fetal heart rate monitoring alone, the use of adjunctive ST waveform analysis made no significant difference to primary outcomes: births by caesarean section (RR 1.02, 95% CI 0.96 to 1.08; 6 trials, n=26 446), the number of babies with severe metabolic acidosis at birth (cord arterial pH less than 7.05 and base deficit greater than 12 mmol/L) (RR 0.72, 95% CI 0.43 to 1.20; 6 trials, n=25 682), or babies with neonatal encephalopathy (RR 0.61, 95% CI 0.30 to 1.22; 6 trials, n=26 410). There were, however, on average fewer fetal scalp samples taken during labour (RR 0.61, 95% CI 0.41 to 0.91; 4 trials, n=9671) although the findings were heterogeneous; there were fewer operative vaginal deliveries (RR 00.92, 95% CI 0.86 to 0.99; 6 trials, n=26 446) and admissions to special care unit (RR 0.96, 95% CI 0.89 to 1.04; 6 trials, n=26 410). There was little evidence that monitoring by PR interval analysis conveyed any benefit.

Comment: The quality of evidence is downgraded by study limitations (unclear blinding of outcome assessment) and by inconsistency (variability in results across studies).

Ədəbiyyat

1. Neilson JP. Fetal electrocardiogram (ECG) for fetal monitoring during labour. Cochrane Database Syst Rev 2006;3:CD000116 [Review content assessed as up-to-date: 23 September 2015].