Does the lying down position for vaginal delivery result in different outcomes for nulliparous mothers or newborns than the upright position?

The lying down position in the second stage of labor resulted in a higher rate of spontaneous vaginal birth (41% vs 35%; number needed to treat [NNT] = 17). Duration of labor was a mean of 7 minutes shorter in the lying down group. There were some trends that also favored the lying down position, but there were no other statistically significant differences in many other outcomes, including instrumental vaginal birth, maternal perineal trauma, infant Apgar score of less than 4 at 5 minutes, and maternal urinary or fecal incontinence one year after delivery. (LOE = 1b)

The Epidural and Position Trial Collaborative Group. Upright versus lying down position in second stage of labour in nulliparous women with low dose epidural: BUMPES randomised controlled trial. BMJ 2017;359:j4471.  [PMID:29046273]

Randomized controlled trial (nonblinded)

Government

Concealed

Inpatient (any location) with outpatient follow-up

This was a randomized controlled trial in 41 UK maternity wards to assess differences in maternal or newborn outcomes when women were instructed to either lay down or stay upright during the second stage of labor. Outcomes were assessed according to the group to which the women were randomized, regardless of the position actually adopted at any time during the second stage of labor. Nulliparous women with low-dose epidural analgesia in the second stage of labor were eligible to participate if they were at least 16 years old, and presented at 37 or more weeks' gestation with a singleton fetus in cephalic presentation. Randomization was concealed, but masking was not otherwise feasible. Women allocated to use an upright position (n = 1556) were instructed to walk, stand, sit, kneel, or adopt any other upright position for as much of second stage labor as possible. Women allocated to use a lying position (n = 1537) were instructed to use a right or left lateral position with up to a maximum 30-degree inclination of the bed. Midwives were instructed to support the women to maintain their allocated position, but ultimately women were free to adopt any position of their choosing. Adherence to the assigned position during active second stage labor was 88% in the upright group and 75% in the lying down group. Spontaneous vaginal birth was significantly higher in the lying down group (41% vs 35%, adjusted risk ratio 0.86; 95% CI 0.78 - 0.94; NNT = 17; 11 - 40). Duration of labor was slightly shorter in the lying down group by a mean of 7 minutes (P = .01). There were some trends toward poorer outcomes in the upright group that were not statistically significant, including instrumental vaginal delivery, cesarean delivery, and perineal trauma. There were no differences in neonatal outcomes or maternal satisfaction. Women were surveyed one year after delivery (61% response) and no statistically significant differences were found for urinary or fecal incontinence, constipation, hemorrhoids, dyspareunia, or health-related quality of life.