Intra-partum fetal monitoring – cardiotocograph

The course of labour is the first challenge one ever undertakes. The uterine contractions during labour exposes the fetus to a possible risk of hypoxic brain injury due to repeated cord compression or reduction of utero-placental perfusion1. Intrapartum fetal surveillance evolved with the principal aim of preventing adverse perinatal outcomes arising from fetal metabolic acidosis / cerebral hypoxia related to labour. However, the severity of an asphyxial injury is influenced by many factors (e.g. tissue perfusion, tissue substrate availability, fetal condition prior to the insult, duration of the insult and the severity of the insult). Therefore, the relationship between metabolic acidosis and cerebral injury is complex. Furthermore, it is clear that very often damage is actually sustained during pregnancy, prior to labour, rather than arising de novo during labour and delivery2 . In spite of this, intrapartum fetal surveillance for early detection of fetal hypoxia has become a key component of modern maternity care. Intrapartum fetal surveillance was traditionally carried out by intermittent auscultation (IA) of the fetal heart rate (FHR). This approach would be adequate to monitor a fetus at low risk of compromise, but may be inadequate for high-risk pregnancies. Therefore, the use of intrapartum electronic fetal monitoring (EFM) with cardiotocography (CTG), has steadily increased over the last three decades in an attempt to reduce the incidence of intrapartum fetal morbidity and mortality.