Ecological Momentary Assessment of Non-Menstrual Pelvic Pain: Potential Pathways of Central Sensitization in Adolescents and Young Adults with and without Primary Dysmenorrhea

PURPOSE: Primary dysmenorrhea (PD; menstrual pain without an identified organic cause) has been proposed as a possible risk factor for the development of chronic pelvic pain, but the mechanism through which this process occurs is unknown. One possible mechanism is central sensitization – alterations in the central nervous system that increase responsiveness to pain leading to hypersensitivity. Repeated episodes of pain, such as those experienced over time with PD, may alter how the brain processes pain. Ecological momentary assessment (EMA; collection of data in real time in participants’ natural environments) is a novel data collection method that may help elucidate pain occurring during non-menstrual cycle phases. PATIENTS AND METHODS: The current observational study assessed the feasibility and acceptability of using EMA via text messages to collect pelvic pain data during menstrual and non-menstrual cycle phases in a community sample of adolescents and young adults (AYA) aged 16–24 years with and without PD and explored occurrence rates and intensity of non-menstrual pelvic pain (NMPP) in each of these groups. RESULTS: Thirty-nine AYA with PD and 53 healthy controls reported pelvic pain level via nightly text message. Global response rate was 98.5%, and all participants reported that the EMA protocol was acceptable. AYA with PD reported higher intensity (2.0 vs 1.6 on 0–10 numeric rating scale; p=0.003) and frequency (8.7% vs 3.1% of days; p=0.004) of NMPP compared to healthy controls. CONCLUSION: The EMA protocol was feasible and acceptable. Though both the intensity and frequency of NMPP were low and at levels that would not typically warrant clinical assessment or intervention, these repeated nociceptive events may represent a potential mechanism contributing to the transition from cyclical to chronic pelvic pain in some individuals.