We present 4 cases of severe intrapartum fetal asphyxia occurring during spontaneous unaugmented labours at term in low-risk women. In each case the baseline heart rate was completely normal, and the only indication of asphyxia was markedly decreased variability detected with electronic fetal heart rate monitoring. Correct action was taken in 3 cases that probably prevented fetal death or reduced neonatal morbidity. In no case would intermittent auscultation have been able to identify the compromised fetus.