Impact of operative vaginal delivery on early postpartum pelvic floor function in primipara

Abstract

Objective To evaluate the effect of operative vaginal delivery on early postpartum pelvic floor function in primipara. Methods Clinical data of 345 parturients with vaginal delivery were collected. According to the mode of delivery， all cases were divided into the natural delivery group （n = 170）， vacuum-assisted delivery group （n = 130） and forceps-assisted delivery group（n = 45）. The pelvic floor muscle strength and three-dimensional ultrasound of the pelvic floor were examined 6-12 weeks after delivery. The abnormal rate of pelvic floor muscle strength， bladder neck mobility rate， cystocele rate， enlargement rate of levator hiatal area， levator ani muscle injury rate， anal sphincter injury rate were statistically compared among three groups. Results There were no significant differences in the maternal age， body mass index， gestational weight gain， gestational age and newborn birth weight among three groups （all P > 0.05）. The abnormal rate of pelvic floor muscle strength in the forceps-assisted delivery group was higher than that in the natural delivery group （P < 0.017）， whereas there were no significant differences in the remaining pairwise comparison （both P > 0.017）. The levator ani muscle injury rate in the forceps-assisted delivery group was higher than those in the natural delivery and vacuum-assisted delivery groups （both P < 0.017）， and the levator ani muscle injury rate in the vacuum-assisted delivery group was higher than that in the natural delivery group （P < 0.001）. There were no significant differences in the abnormal rate of bladder neck mobility， cystocele rate， enlargement rate of levator hiatal area and anal sphincter injury rate among three groups （all P > 0.05）. Pelvic floor ultrasound indicated that among 52 women with pelvic floor muscle injury， 9 cases had normal pelvic floor muscle strength. The results of consistency test between two methods were Kappa = 0.061 and P = 0.029. Conclusions Compared with the natural delivery group， the pelvic floor injury is the most severe and the levator ani muscle injury rate is the highest in the forceps-assisted delivery group. These two methods are independent of each other. Pelvic floor ultrasound can clearly show pelvic floor muscle injury after delivery， which plays an important role in the postpartum screening of pelvic floor.

Keywords

• |operative vaginal delivery|pelvic floor muscle strength|pelvic floor ultrasound|vacuum-assisted delivery|forceps-assisted delivery