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

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.