BACKGROUND AND PURPOSE:

• The original trial by this study team did not find a significant improvement with gabapentin (determined by the tampon test) in women with localized provoked vulvodynia (PVD)
• Bachmann et al. (AJOG, 2019) performed a secondary analysis to determine whether extended-release gabapentin was effective in improving sexual function in women with PVD

METHODS:

• Secondary outcome of a multicenter double-blind, randomized crossover trial (RCT)
  • Patients with localized PVD, formally known as vulvar vestibulitis
  • 18-week time frame
  • 6 weeks per treatment period
    • 4-week dose titration | 2-week maintenance dose | 4-day washout period
  • Patients received either
    • Gabapentin (1200 to 3000 mg/d)
    • Placebo
  • Outcomes assessed
    • Sexual function, measured by FSFI
    • Stratified based on baseline provoked pelvic muscle pain severity scores
  • 56 pain-free control subjects, matched by age and race, also completed Female Sexual Function Index (FSFI) for comparison to determine if sexual function in women with PVD would be similar either before or after treatment

RESULTS:

• 230 women were screened at 3 academic institutions
  • 89 participants
• Gabapentin was more effective than placebo in improving
  • Overall sexual function: Adjusted mean difference (MD) 1.3 (95% CI, 0.4-2.2; P=.008)
  • Desire: MD 0.2 (95% CI, 0.0-3.3; P=.04)
  • Arousal: MD 0.3 (95% CI, 0.1-0.5; P=.004)
  • Satisfaction: MD 0.3 (95% CI, 0.04-0.5; P=.02)
• Despite improvement, function remained significantly lower than matched vulvodynia pain-free control subjects
• No improvement seen for orgasm, lubrication, or pain domains
• Gabapentin improved outcomes in women with high but not low pelvic muscle pain severity scores
  • Full Female Sexual Function Index scale: MD 1.6 (95% CI, 0.3-2.8; P=.02)
  • Arousal: MD 0.3 (95% confidence interval, 0.1-0.6; P=.01)
  • Pain domain scores did not reach statistical significance (P=.04)

CONCLUSION:

• Gabapentin improved sexual function in women with provoked vulvodynia, particularly those with increased pelvic muscle pain on exam
• However, overall sexual function remained lower than women without the disorder

Learn More – Primary Sources:

Effect of gabapentin on sexual function in vulvodynia: a randomized, placebo-controlled trial.

Related ObG Topics:

Is Gabapentin an Effective First Line Drug for Vulvodynia?

Evaluating Vulvodynia – Making the Diagnosis and Key Management Points