MATERNAL OUTCOMES IN NULLIPAROUS WOMEN WHO GAVE VAGINAL BIRTH ON A BIRTH SEAT OR IN ANY OTHER POSITION: RESULTS OF A RANDOMISED CONTROLLED TRIAL IN SWEDEN

Background: Upright birth positions may reduce the risk for instrumental delivery. The aim of this study was to test, by means of a randomised controlled trial, the hypothesis that the use of a birthing seat during the second stage of labour decreases the number of instrumental deliveries and thus counterbalance any adverse perineal outcome or severe blood loss.Methods: One-thousand and two nulliparous women were randomised to give birth either on a birth seat or to give birth in any other position except for the birth seat. The primary outcome was the number of instru-mental deliveries. Secondary outcomes included perineal outcome, mater-nal blood loss and haemoglobin, length of the second stage of labour. Analysis was by intention to treat.Results: The main fi ndings of this study were that birth seat births did not reduce the number of instrumental vaginal births; there was an increase in blood loss >500 mL in women who gave birth on the seat, but no increase in bleeding >1000 mL. No increase in 3rd degree perineal traumas or perineal oedema. Second stage was signifi cantly shorter in the experimental group.
Conclusions: The birth seat did not reduce the instrumental vaginal births. The study confi rmed an increased blood loss 500 mL–1000 mL, no adverse consequences for perineal outcome as well as shorter second stage for birth seat births