Standards in fetal monitoring

Fetal monitoring by cardiotocogram (CTG), fetal blood gas analysis (FBA) and pulse oximetry are mostly accepted by obstetricians. Other new methods are in discussion. Cost, benefit and need of the different methods are in continuous controversy. Successful screening by monitoring is focused on early detection and prevention of fetal asphyxia. Though the predictive value of fetal acidosis by CTG is only 30%, the cardiotocogram is the accepted standard method of fetal monitoring. In cases of difficult assessment of intrapartum CTG (4-6%) additional FBA is recommended. Perinatal statistics demonstrate no advantage of continuous monitoring. Intermittend electronic monitoring therefore is possible in deliveries without risk factors. The increasing rate of cesarean sections is followed by defensive medicine and not caused by fetal monitoring. Provided standards of fetal monitoring severe asphyxia in newborns with more than 1500 g is expected in 1:5000 to 1:10000 deliveries. The benefit of additional methods therefore seemed to be hardly to prove by prospective trials.