Botulinum Toxin Treatment of Pelvic Floor Disorders and Genital Pain in Women

Abstract

Background and Objective: Botulinum neurotoxin (BoNT), now commonly used for reducing muscular spasms in other neuromuscular disorders, is now increasingly proposed also for treating pelvic floor disorders, including chronic pelvic pain syndromes, vaginismus, vulvodynia and vulvar vestibulitis syndrome. To provide up-to-date information on these advances we reviewed the literature about BoNT injections for pain and spasms related to pelvic floor disorders. Methods: We conducted a Medline search using the terms botulinum neurotoxin, pelvic floor disorders, levator ani myalgia, vaginismus, vulvar vestibulitis, vulvodynia, dyspareunia, interstitial cystitis, recurrent cystitis, and postcoital cystitis. We sought information on the indications and techniques used for BoNT treatment for pelvic floor dysfunctions, and related pain syndromes in women. Results: Our search identified 12 studies for review (including a randomized controlled trial) showing that BoNT effectively reduces pain in chronic genital pain syndromes associated with pelvic floor spasm. Before BoNT trials, patients with idiopathic lifelong vaginismus and dyspareunia, associated with hyperactive pelvic floor muscles, had no effective treatment options. BoNT injected under electromyographic (EMG) guidance in pelvic floor muscles improves vaginismus, helping to restore a normal sexual life. BoNT injections also seem to improve vulvodynia and vulvar vestibulitis. Though some patients need periodic injections, in about 65% of affected women BoNT achieves permanent benefit. Conclusions: These encouraging evidence-based results suggest that BoNT injected intramuscularly should extend treatment options for women with lifelong or acquired pelvic floor disorders and genital pain. Keywords: Pelvic floor disorders, urinary dysfunctions, chronic pelvic pain, vaginismus, vulvar vestibulitis syndrome, EMG, botulinum toxin type A