Delivery in an obstetric birth chair: a randomized controlled trial

OBJECTIVE: To determine whether nulliparae whose second stage of labour is conducted in an obstetric birth chair have a lower incidence of instrumental delivery than those using a conventional delivery bed. DESIGN: Randomized controlled trial using sealed, opaque envelopes for allocation. SETTING: Delivery ward in a busy teaching hospital. PATIENTS: 1250 nulliparae with a singleton live fetus with cephalic presentation, without epidural anaesthesia, who had achieved full dilatation. INTERVENTION: Intention to conduct second and third stages of labour in either the Birth-EZ chair or the conventional delivery bed, as randomly allocated. MAIN OUTCOME MEASURES: Primary measure: vaginal operative delivery; principal secondary measures: duration of second stage, perineal trauma, blood loss, women's views, and neonatal status. RESULTS: Delivery in the birth chair did not result in a reduction in operative delivery, overall. However, there was a reduction in vaginal operative delivery for fetal heart rate abnormality. There was no beneficial effect on perineal trauma or puerperal perineal pain. Post-partum haemorrhage was more frequent in the birth chair group. CONCLUSIONS: Delivery in the birth chair does not offer any obvious advantage to women over delivery on a bed.