Dysmenorrhea subtypes exhibit differential quantitative sensory assessment profiles.

Area of Science:

• Pain research
• Gynecology
• Urology

Background:

• Dysmenorrhea (painful periods) is common in women who develop chronic pelvic pain conditions like bladder pain syndrome (BPS).
• The role of menstrual pain in the development of chronic pelvic pain remains understudied.
• Altered pain processing mechanisms may link dysmenorrhea to other visceral pain conditions.

Purpose of the Study:

• To systematically characterize bladder, body, and vaginal mechanical sensitivity in women with dysmenorrhea (DYS) and BPS.
• To compare sensory profiles between DYS, BPS, and healthy controls (HCs).
• To identify predictors of pain symptoms within the DYS group.

Main Methods:

• Quantitative sensory testing (QST) was used to assess mechanical sensitivity and pain responses.
• Participants included women with DYS (n=147), HCs (n=37), and BPS (n=25).
• A subset of DYS participants were further classified as DYSB (n=49) based on bladder hypersensitivity.

Main Results:

• DYS, DYSB, and BPS groups exhibited lower vaginal mechanical thresholds and increased pain sensitivity compared to HCs.
• DYSB participants showed reduced body mechanical thresholds and impaired conditioned pain modulation.
• Provoked bladder pain significantly predicted self-reported menstrual pain, bladder pain, dyspareunia, and bowel pain in the DYS group.

Conclusions:

• Women with dysmenorrhea exhibit widespread sensory sensitivity, indicating altered pain processing mechanisms.
• Provoked bladder pain is a significant predictor of other chronic pelvic pain conditions.
• Further research is needed to understand the trajectory of pain processing alterations in preclinical visceral pain phenotypes.