Botulinum toxin type A-a novel treatment for provoked vestibulodynia? Results from a randomized, placebo controlled, double blinded study

Abstract

Introduction: Vestibulodynia is an increasingly recognized problem among women and is often difficult to treat.

Aim: This randomized, double blinded, placebo-controlled study aimed to evaluate the efficacy of Botox in the treatment of vestibulodynia.

Methods: Sixty-four women were randomized to receive Botox (N = 32) or saline placebo (N = 32). Botulinum toxin A (20 I.E.) diluted in 0.5 mL saline or 0.5 mL saline was injected in the musculus bulbospongiosus at baseline.

Main outcome measures: Pain was measured monthly on a visual analog scale (VAS) Likert scale. Sexual function was measured using the Female Sexual Function Index (FSFI) and the Female Sexual Distress Scale at baseline and at 3 and 6 months follow up. Quality of life was measured using the 36-item short-form (SF-36).

Results: Sixty women (94%) completed the 6 months follow up. Both Botox and placebo produced significantly pain reduction (P < 0.001). There was no significant difference in the median VAS score between the groups at 6 months follow up (P = 0.984). An improvement on the FSFI full score from baseline until 6 months was not significantly different between the groups (P = 0.635). In the placebo group a statistical significant larger reduction in sexual distress was observed from baseline until 6 months follow up compared to the Botox group (P = 0.044). No statistical significant differences were observed between the B- and P-groups in regard to the SF-36 scores.

Conclusion: Injection of 20 I.E. Botox in the vestibule of women diagnosed with vestibulodynia does not reduce pain, improve sexual functioning, or impact the quality of life compared to placebo and evaluated at 3 and 6 moths follow up. Both the Botox group and the placebo groups experienced a reduction in pain on the VAS Likert scale at 6 months follow up. Women with vestibulodynia have difficulty with sexual function and present with sexual distress, which has to be addressed in conjunction with pain to eliminate the disorder.