Chronic Pain Risk Associated With Menstrual Period Pain

Endometrial shedding during the menstrual cycle elicits profound changes in neuronal activity and cytokine concentrations producing moderate to severe pelvic pain in more than 20% of reproductive-age women. One out of every five of those women in turn will develop chronic pelvic pain (CPP), yet women without dysmenorrhea rarely report CPP. CPP disorders such as irritable bowel syndrome (IBS) and painful bladder syndrome (PBS) can cause severe, unrelenting pain due to a lack of effective treatments.

This study consists of 2 aims.

Aim #1: To determine if dysmenorrhea with concomitant bladder pain sensitivity exhibits neurophysiological features consistent with established CPP. Women with chronic pain or dysmenorrhea without COS will be used as controls. Quantitative sensory testing (QST) and a noninvasive bladder pain test that investigators validated previously be used to determine whether impairments in descending inhibition and pelvic sensitivity are responsible for vulnerability to COS in women with dysmenorrhea. EEG will be recorded to look for differences in brain activity in response to sensory stimulation between participants cohorts.

Aim #2: To differentiate the individual contributions of circulating sex hormones and repeated sensitizing events (painful menses) on descending and peripheral mechanisms of bladder pain. The same QST/bladder pain measures studied in Aim #1 will be retested within the dysmenorrhea+COS group following a one-year randomized trial of cyclical OCs vs. continuous OCs vs. no treatment. An observational arm of PBS participants will receive continuous OCs and serve as controls.

Inclusion criteria

All

• Reproductive age women (18-45)

For dysmenorrhea and D+COS group only:

• Participants must have had regular (22-45 day) menstrual cycles over at least a two month period preceding testing

Exclusion criteria

All

• presence of active pelvic or abdominal malignancies (primary or metastatic)
• active genitourinary infection in the last four weeks
• unable to read or comprehend the informed consent in English
• unwilling to undergo pelvic examination/testing
• presence of hypertension or risk for developing hypertension, and

For dysmenorrhea and D+COS group only:

• absence of regular menses (including current pregnancy, recent pregnancy, or active breast feeding) unwilling to take either cyclic or combined OCs
• unwilling to withdraw from OCs for two months prior to the sensory testing study visit.