Hypoxaemic episodes during the 2nd stage of labour in parturients receiving different forms of pain relief. NA = No Analgesia PE = Pethidine + Entonox EB = Epidural Bupivacaine EBF = Epidural Bupivacaine + Fentanyl Reproduced with permission of the editor of Anaesthesia and RP Griffin and F Reynolds. Anaesthesia 1995; 50:151-156.