Adolescent Dysmenorrhoea as a Risk Factor for Chronic Pain: Clinical Cohort Study

This study aims to understand whether changes in a variety of body systems which are seen in adult women with period pain are also seen in adolescents in the first few years of having periods. This information will help to understand 1) how quickly any changes occur, informing clinical practice, and 2) how period pain might lead to other types of chronic pain, potentially allowing development of preventative strategies.

Chronic pain is defined as pain that lasts for more than 3 months. It is really common, affecting up to 30% of people worldwide with impacts on all areas of life. Chronic pain is difficult to treat once it has developed. Therefore, understanding which people might be at risk of developing chronic pain and protecting them from it starting, would be a really positive step forward.

It is known that women are more likely to develop almost all types of chronic pain than men. This sex difference in chronic pain starts to be seen after puberty, suggesting that changes happening at this time may be contributing to this increased risk. One important change that happens at this time is periods starting. Despite periods often being very painful, period pain has traditionally been dismissed as "normal" and something girls must learn to live with. However, in adult women with period pain many differences are seen across a range of body systems when compared to women without period pain. These include increased sensitivity to pain; increased sensitivity of the bladder, bowel and womb; altered brain structure and function; and altered responses to stress. Similar changes to those seen with period pain can be seen in other chronic pain conditions. It is not known whether these changes are caused by repeated or continuous pain or if they are part of the reason why chronic pain develops, or a combination of both.

The RoADPain Clinical Study aims to see whether the differences in other body systems described above in adult women with period pain are also seen in girls in the first few years of having periods. The investigators will combine detailed questionnaire data with tests of the function of a variety of systems (including nerve function, stress response and brain imaging). No study treatment or intervention will be given. It is envisaged that this information will help to understand 1) how quickly any changes occur, informing clinical practice, and 2) how period pain might lead to other types of chronic pain, potentially allowing development of preventative strategies.

Eligibility Criteria:
Inclusion Criteria:

* Participant (or parent/guardian of participant) is willing and able to give informed consent for participation in the study.
* Female or assigned female at birth.
* aged 11 - 20 years.
* At least 6 periods per year since menarche.
* During the study data collection period will be within one of the following time intervals since menarche:
* 12 - 15 months
* 36 - 39 months
* 60 - 63 months
* Reports either period pain or no pain with periods and scores appropriately on NRS (period pain: ≥4/10; no period pain: ≤3/10).
* Not using hormonal therapies (i.e. contraceptives) currently and has not used previously.
* Reasonably fluent in English.

Exclusion Criteria:

* Current or previous chronic pain condition other than dysmenorrhoea, including migraine.
* Pregnant or breast-feeding.
* Previous cancer diagnosis.
* Contraindication to MRI