Objective and Methods Sudden collapse of apparently well term infants within hours of birth is a rare but recognised event. In many cases an underlying cause will be found, but a few remain unexplained. This group of infants are characterised by a high mortality and poor neurological outcome but are unrecognised in national statistics, and therefore the population incidence is uncertain. Following a cluster of cases in our hospital we undertook a review of such infants to identify common features and relative frequency.

Results Over a 2-year period, five infants, previously assessed as healthy, were found collapsed in the care of their primiparous mothers within 12 hours of birth. Two were found prone on their mother’s chest who was undergoing episiotomy repair, two further infants were lying alongside their sleeping mother and one was in her mother’s arms in a dark room. Despite full resuscitation and intensive care, the outcome was poor with four neonatal deaths and one death aged 18 months with severe neurological impairment. The rate of sudden unexplained neonatal collapse was 0.4 per 1000 live births. No cause for collapse was identified despite extensive investigations, including post mortem in all the neonatal deaths. One infant, however, showed widespread antenatal brain damage at post mortem.

Conclusion We postulate that some infants with an underlying vulnerability may maladapt to extrauterine life following a hypoxic stressor possibly caused by suboptimal airway positioning. We suggest national studies to investigate the incidence and epidemiology of early sudden neonatal collapse.