AbstractChanging patterns of instantaneous heart rate associated with apnea were analysed in 22 neonates; ten sleepy infants due to analgesic agents used during delivery, five preterm infants with favourable outcome and seven sick neonates with major medical complications. Patterns of heart rate change were classified into five types: type I deceleration, which is a sharp drop of heart rate synchronized with apnea; type II deceleration, which is a gradual decrease of heart rate during apnea; type III decerelation, which is a bradycardic spell without consistent relation with apnea; acceleration, which is a rapid increase of heart rate associated with respiration change; and a non‐reactive type, in which there is no appreciable heart rate change during apnea. Type II deceleration, type III deceleration and the absence of acceleration were strongly related with poor clinical conditions. Type I deceleration was frequently observed in most neonates with apnea and was not necessarily regarded as an ominous finding. The non‐reactive type was seen in both cases, with favourable and unfavourable outcome. Application of the knowledge of fetal heart rate monitoring to neonatal monitoring is possible and is rather promis