A multicentre, randomised controlled trial of position during the late stages of labour in nulliparous women with an epidural: clinical effectiveness and an economic evaluation (BUMPES)

Background: Epidural analgesia leads to increased risk of instrumental vaginal delivery (IVD). There is debate about whether or not posture in second-stage labour influences the incidence of spontaneous vaginal birth (SVB). Objectives: In nulliparous women with epidural analgesia, does a policy of adopting an ‘upright position’ throughout second-stage labour increase the incidence of SVB compared with a policy of adopting a ‘lying-down’ position? Design: Two-arm randomised controlled trial. Setting: Maternity units in England and Wales. Participants: Nulliparous women aged ≥ 16 years, at ≥ 37 weeks’ gestation with singleton cephalic presentation and intended SVB, in second-stage labour with an epidural providing effective pain relief. Interventions: (1) Upright position to maintain the pelvis in as vertical a plane as possible; and (2) lying-down position to maintain the pelvis in as horizontal a plane as possible. Main outcome measures: The primary outcome measure was incidence of SVB. Secondary outcomes included augmentation, interventions to maintain blood pressure, duration of labour, episiotomy, genital tract trauma, post-partum haemorrhage, maternal satisfaction, neonatal metabolic acidosis, 5-minute Apgar score of