Liu J, et al. - A meta-analysis of randomized controlled trial (RCT) studies was performed to evaluate the effect of Membrane sweeping (MS) added to formal induction method on the spontaneous vaginal delivery, compared with formal induction alone. A significant increased vaginal delivery rates were evident in association with MS added to formal induction compared with formal induction alone. This was especially observed in nulliparas. Researchers noticed no obvious side effects of MS.