Gynecological indications for the use of botulinum toxin in women with chronic pelvic pain

Abstract

Chronic pelvic pain in women is a common symptom with a wide variety of etiologies that demand accurate diagnosis and appropriate treatment if pain reduction is to be effected. Superficial conditions such as provoked vestibulodynia and problems affecting deeper structures such as pelvic floor muscle spasm are difficult to treat and can have significant impacts on quality of life for the sufferer. Apart from daily pain, symptoms such as painful intercourse (dyspareunia), painful bowel motions (dyschesia) and exacerbation of period pain (dysmenorrhea) are commonly reported by patients. For inflammatory conditions, and in areas where muscle spasm is thought to contribute to pain, botulinum toxins (BoNT) are used with considerable success. For gynecological indications, there are limited data, in the form of case reports and small series, to indicate that BoNT used in the vulva may have a benefit for 3–6 months after injection of 20–40 U of BOTOX ®; for women with provoked vestibulodynia. Re-treatment is reported to be successful and side effects are limited. Controlled studies are essential to further explore this indication. For pelvic floor muscle spasm, a greater number of women have been studied and a double blind, randomized controlled study has reported a significant reduction in pelvic floor pressures with significant pain reduction for some types of pelvic pain compared to baseline. There were no differences in pain compared to the control group who had physical therapy as an intervention. Physical therapy could be used as a non-invasive first line treatment, with BoNT injections reserved for those who are refractory to treatment. In summary, BoNT treatment for a variety of gynecological indications seems successful with limited side effects, although there are minimal data, particularly in superficial vulval conditions. To allow recommendation for wider utilization of this treatment, it is essential that more research is performed to add further evidence to our current knowledge.