Fetal heart monitoring

The use of an instrument to record and/or listen to an unborn baby’s heartbeat during pregnancy and labour. Monitoring is carried out at intervals throughout pregnancy if tests indicate that the placenta is not functioning normally or if the baby’s growth is slow. During labour, monitoring can detect fetal distress, in which oxygen deprivation causes abnormality in the fetal heart-rate. The simplest form of fetal heart monitoring involves the use of a special fetal stethoscope. Cardiotocography, a more sophisticated electronic version, makes a continuous paper recording of the heartbeat together with a recording of the uterine contractions. The heartbeat is picked up either externally by an ultrasound transducer strapped to the mother’s abdomen or, as an alternative during labour, internally by an electrode attached to the baby’s scalp that passes through the vagina and cervix.