The prediction of fetal acidosis at birth by computerised analysis of intrapartum cardiotocography

Abstract

Objective: To assess the capability of a computer software interpretation program, using intrapartum fetal heart rate and intrauterine pressure as recorded in a cardiotocogram to predict fetal acidosis at birth.

Design and subjects: A retrospective analysis of digitised fetal heart rate and uterine activity values obtained from 73 high risk women in labour.

Setting: Two university teaching hospitals.

Methods: A computer software program was constructed to analyse the digitised data and predict acidosis. The results of the analysis were compared with actual umbilical arterial blood pH and base excess at delivery.

Results: The software cardiotocogram interpreter was able to predict a pH of less than 7.15 with an accuracy of 77%, a sensitivity of 88% and specificity of 75% in this set of data. It was able to predict a base excess of less than -8 mmol/l with an accuracy of 81%, a sensitivity of 76% and specificity of 82%.

Conclusions: A computerised method of analysing fetal heart rate and uterine activity using a simple algorithm has demonstrated a capability to predict fetal acidosis at the time of delivery. Further research in this area is warranted.