Long-term effects of the nine-item list intervention on obstetric and neonatal outcomes in Robson group 1 - A time series study.

Implementation of the nine-item list increased the proportion of spontaneous vaginal deliveries by reducing the number of instrumental deliveries and cesarean sections without affecting the neonatal outcomes in nulliparous women with spontaneous onset of labor. The nine-item list intervention seems to provide long-term sustainable results.