Nuchal encirclement by the umbilical cord is a common cause of fetal distress, and may result in neonatal depression and acidaemia. Severe irregularity of the fetal heart gives prolonged warning of the condition. The temporal relationship of transient episodes of bradycardia to uterine contractions is not helpful in differentiating cord entanglement from other causes of fetal hypoxaemia. Tipton, R. H. (1971): M.D. Thesis, Sheffield University. Tipton, R. H., and Shelley, T. (1971): Journal of Obstetrics and Gynaecology of the British Commonwealth. 78,702.