Pain in Women
Chronic pain is defined as pain lasting for more than 6 months.
In the UK alone, approximately 7.8 million people live with chronic pain with, at any time, over a third of households containing someone in pain.
Our work aims to optimise pain relief and quality of life for women with chronic pain by improving our understanding of the mechanisms generating pain in women and the interaction between hormones and pain.
what we do
Chronic pain is defined as pain lasting for more than 6 months. In the UK alone, approximately 7.8 million people live with chronic pain with, at any time, over a third of households containing someone in pain. Women suffer with almost all chronic pain conditions to a much greater extent than men. Additionally, they also suffer from female-specific pains; particularly in their pelvis, including period pain (dysmenorrhoea) and the pains associated with diseases such as endometriosis. Unfortunately, it is frequently difficult to treat chronic pain and attempts at finding new drugs have not usually been successful. Our work focuses on two aspects of pain specific to women. Firstly, we are interested in better understanding the mechanisms generating and maintaining pain in gynaecological pain conditions such as dysmenorrhoea and endometriosis. Secondly, we are investigating the relationship between steroid hormones and pain. In the long-term we hope to be able to optimise both analgesia and quality of life for women with chronic pain whatever its original cause.
Epidemiology of chronic pelvic pain:
Our past work has shown that chronic pelvic pain (constant or intermittent lower abdominal pain unrelated to periods or intercourse, lasting for six months or more) is common, with up to 24% of women reporting having experienced such pain in the UK. The extent to which the lives of women are affected by the pain varied widely, and our studies of general practice records showed that annually approximately 4% consult a GP for their symptoms. Most women with chronic pelvic pain also reported pain with periods and intercourse, and many had additional bowel or bladder related symptoms, which complicated differential diagnosis and meant that over time they often received several ‘diagnoses’ including irritable bowel syndrome, cystitis, endometriosis, chronic pelvic inflammatory disease, and ‘stress’.
Associations of dysmenorrhoea:
Period pain (dysmenorrhoea) is common, affecting up to 90% of women at some time in their life. Our work combined brain imaging (functional magnetic resonance imaging (fMRI)) with hormone levels and psychological measures to investigate the long-term consequences of experiencing pain for one or more days every month. Even though the women we studied had no pain outside of their periods we found that they showed many of the long-term changes seen in other chronic pain conditions. Thus, even though they were psychologically healthy (normal levels of anxiety and depression), they were more sensitive to experimental pain, showed altered brain processing of these painful stimuli and had reduced levels of cortisol (a stress hormone) in their blood. In combination with other recent studies showing altered brain structure in women with dysmenorrhoea our findings contributed to the reclassification of dysmenorrhoea as a chronic pain condition in the most recent IASP taxonomy of pain.
The influence of sex hormones on acute pain in healthy women:
Even non-gynaecological pain conditions frequently show variation in symptom severity with the menstrual cycle. We have combined fMRI with measures of blood hormone levels to investigate the relationship between specific hormones and the response to painful stimuli and to try to understand the mechanisms underlying these findings. Our results suggest that steroid hormones interact with known internal pain-modulating mechanisms. For example, when estrogen levels are low it appears that testosterone is important in reducing pain, whilst when estrogen levels are high progesterone reduces the unpleasantness of a pain experience. We are now investigating whether these relationships are the same for women with chronic pain conditions.
The primary aim of the EndoPAIN study is to identify factors predicting the response to surgery in women with endometriosis-associated pain. Women with pelvic pain thought to be due to endometriosis who are scheduled to have a laparoscopy are assessed prior to surgery (including an fMRI brain scan) and then followed up for 6 months after surgery. We also hope this study will help us understand the differences and similarities between the mechanisms generating pain in women with pelvic pain with and without endometriosis. If you are interested in being involved in this study please email Lisa Buck.
WIPSOx1 is the first of a series of studies investigating factors relating to Women In Pain in Oxford. WIPSOx1 is specifically looking at the impact of chronic pain on hormone levels in women between 18-50 years old. We already know that most chronic pain conditions are associated with a reduction in blood cortisol levels and that many other types of stress (e.g. weight loss, exams, etc) can cause periods to temporarily stop or become irregular. We are interested in whether pain is itself enough of a stressor to affect hormone levels and if so whether this is associated with alterations in quality of life (e.g. mood, libido etc) or long-term health risks. We are currently recruiting participants for this study so if you think you might be interested in being involved, please email Lisa Buck, call 07802 861 666 or visit our Facebook page.
In collaboration with Edinburgh and a number of other pelvic pain clinics around the country, GaPP2 (Gabapentin for Pelvic Pain) study will investigate the benefit of gabapentin in chronic pelvic pain of unknown cause. Although gabapentin is frequently used in other chronic pain conditions there is little evidence to support its use in pelvic pain specifically and a poor understanding of how it works in women in general.
GaPP2 is now recruiting participants, if you would like more information, please email Lisa Buck, call 07802 861 666 or 01865 221120,