This is an excellent guideline and well worth a read. A lengthy summary I’m afraid.
Chronic Pelvic Pain is described as pain for at least 6 months which is not just related to menstruation, intercourse or pregnancy.
There is a big emphasis in the guideline on looking at pain as both a physical and an emotional response to a stimulus. The emotional response comprises psychological and social elements. It has been shown that addressing all these elements from the start, is much more successful than just addressing the physical aspect.
You can explain to women that pain modulation occurs at CNS and PNS level. Chronic pain is associated with changes in both the afferent and efferent nerves, long after any local stimulus has gone. As the nerves alter you get ‘visceral hyperalgesia’, which is an alteration in visceral sensation and function. All this can follow surgery, infection, trauma, fibrosis or inflammation. Therefore all evidence of the original underlying cause may be long gone.
Causes of Chronic Pelvic Pain:
- Endometriosis and Adenomyosis – marked cyclical variation, often with dyspareunia.
- Pelvic Venous Congestion – uncertain if this exists, but women with suggestive symptms (mainly just cyclical pain) respond to hormonal treatments.
- Adhesions – may cause pain, but studies show that adhesionlysis doesn’t make much difference, except perhaps with very dense venous adhesions.
- IBS and Interstitial cystitis – both can have a slight cyclical element.
- Musculoskeletal – increasing evidence that musculoskeletal pain can be involved, either of the pelvic girdle or of deep trigger points. Prolapse can also cause pelvic pain.
- Nerve Entrapment – Tends to be very localised pain.
- History – ensure you include social and psychological factors. Also ask about the effect of posture and for bladder and bowel symptoms. A pain diary can be helpful for 2 to 3 cycles.
- Functioning – how does this interfere with work / life
- Red Flags – these are pretty obvious (eg weight loss, new pain post menopause, irregular menstrual bleeding in the over 40s or post-coital bleeding, PR bleeding or new onset IBS symptoms in the over 50s).
- ICE – asking a woman’s ideas about her pain has been shown to improve her experience and also chance of a satisfactory outcome.
- Examination – ensure you have plenty of time to do this. Include checking the SI / pelvic girdle joints.
- Swabs for infection
- CA125 (if satisfy criteria)
- Transvaginal ultrasound – will miss endometriosis
- MRI may be considered if palpable nodules or retrovaginal disease suspected
- Laparoscopy – used to be the gold-standard but is being done less now for the following reasons:
- Risks - Comes with 1 in 10000 risk of death and 2.4 in 1000 risk of damage to bladder or bowel.
- Won’t find IBS / adenomyosis / some forms of endometriosis.
- 30 to 50% laparoscopies are negative and not all pathology seen is the cause of the pain felt (if there is a completely normal ultrasound, only 20% of laparoscopies show any pathology).
- Been shown not to alter pain experience – whether anything found or not.
Therefore normal procedure would be to do swabs and an ultrasound, then try treatment, then refer for possible laparoscopy if treatment fails. If the woman has specific concerns such as endometriosis or adhesions affecting fertility, then an earlier laparoscopy may be indicated.
Medication and Treatment:
- Hormonal – COC, POP, danazol or GnRH analgoues are all equally effective. Mirena can be tried too. They can help with non-cyclical pain as well as with cyclical pain.
- Analgesia – NSAIDs and paracetamol should be tried first. Amitriptyline and gabapentin can be tried. TENS, acupuncture and non-conventional treatments may help some women, as may dietary modification (most commonly dairy and grains).
- Expert Patient – Psychological support, or expert patient initiatives can make a big difference to the pain experience.