Randomized, Double-Blind, Placebo-Controlled Trial on the Efficacy of Hyaluronidase in Preventing Perineal Trauma in Nulliparous Women

PURPOSE: Hyaluronidase (HAase) has many uses in medicine, and reports suggest that it affects perineal tissue during fetal passage through the vaginal canal. However, its potential use for preventing perineal trauma has yet to be determined. This study sought to evaluate the efficacy and safety of perineal HAase injections in reducing perineal trauma during vaginal delivery. MATERIALS AND METHODS: A multi-center, double-blind, placebo-controlled, randomized study was conducted from January 2016 to March 2017. Nulliparous women who planned to undergo vaginal delivery were recruited, and the enrolled women were randomly assigned to the HAase injection group (HAase injection, 5000 IU, n=75) or the control group (normal saline injection, n=73). The degree of perineal laceration, rate of episiotomy, and grade of perineal edema at 1 hour and 24 hours after spontaneous vaginal delivery were compared between the two groups. RESULTS: A total of 148 women who underwent vaginal delivery were recruited. No significant differences were observed between the HAase injection and control groups in the rates of perineal laceration (p=0.422). Perineal edema significantly decreased 24 hours after delivery in the women treated with perineal HAase injections, compared to women in the control group (p=0.008). The overall incidences of adverse events, such as redness of the injection site, infection, and wound dehiscence, were similar between the two groups. CONCLUSION: HAase injections in nulliparous women afforded no reductions in the rates of perineal lacerations and episiotomy. However, the use of perineal HAase injections did reduce perineal edema without severe adverse events.