Intrapartum foetal hypoxia represents one of the most frequent causes of the hypoxia-ischemia CNS injury in newborns and it can result in the development of a permanent handicap. It often results from the underestimation of the development of the delivery by the obstetrician who conducts delivery and who is responsible for it. That is why the contemporary obstetrics is using new instruments, enabling to evaluate objectively the development of the intrapartum foetal hypoxia. The praxis consequently introduced cardiotocography (CTG), foetal pulse oximetry (FpO2) and recently new methods for evaluation of ST interval in foetal ECG- STAN. The last method has the highest specificity for prediction of the foetal hypoxia and it properly signalises the development of the metabolic foetal acidosis, which threatens the foetus during delivery and which can impair the vital organs. Foetal myocardium sensitively responds to the release of stress hormones, to the development of anaerobic metabolism and to the increase of potassium levels. The development of hypoxia manifests in ECG as a subsequent rise of T wave, elevation of T/QRS segment and as a significantly biphasic ST interval. The last sign indicates serious state of the foetus in utero accompanied with metabolic acidosis.