Abstract:Objective To study the effect of different delivery modes on vaginal resting pressure (VRP), pelvic floor muscle (PFM) strength and endurance, and to further explore the differences in these measurements between pregnant women with and without urinary incontinence. Methods Eight hundred women who underwent natural childbirth (vaginal delivery, group A), cesarean section women (group B), midwifery (group C) and also non-pregnant nulliparous women (group D) were chosen and each group included two hundred women. The change of VRP, PFM strength and endurance were tested at mid-pregnancy (21 gestational weeks) and 6th week after childbirth. Results In the groups A, B and C, VRP significantly decreased at 6th week after parturition compared with that at mid-pregnancy (P < 0.05). In the groups A and C, PFM strength and endurance significantly reduced at 6th week after parturition compared with those at mid-pregnancy (P < 0.01). There was no significant difference in the VRP or PFM in the group D (P > 0.05). In the 6th week after parturition, VRP, PFM strength and PFM endurance significantly reduced in the groups A and C compared with those in the group B (P < 0.01); while VRP and PFM showed no significant differences between the group A and the group C (P > 0.05). Conclusions Nature childbirth can reduce vaginal resting pressure, pelvic floor muscle strength and endurance more than other delivery modes.