It could be a range of causes. She shouldn't just focus on one particular illness, not yet. Like other conditions, the GP manages the majority of it and can only refer when someone meets the threshold for specialist intervention. The GP has to do some tests, investigations, try some other forms of management first. Otherwise, gyne will just reject the referral. She may even just have primary dysmenorrhea (which has no cause or underlying condition with it, but of course this should only be decided after all investigations are done). She may have PCOS, and her symptoms sound more like adenomyosis than endometriosis. So it's not the time for referral yet.
@Charliebean I recommend her trying tranexamic acid to help with the bleeding and maybe a mirena coil. The mirena does treat the real cause as well (mirena will may the uterus lining thinner, less bleeding, and less cramps). For the pain, try NSAIDs like Naproxen or mefenamic acid. Blood tests can spot other issues, but also get her a pelvic and transvaginal ultrasound.
Has she had long-term and chronic issues with mobility, back and sciatica, debilitating pelvic pain, pain with sex and insertion to the vagina, severe vomiting and nauesa, cycles of severe constipation and/or diarrhoea. Are her symptoms just on your period or elsewhere during the month? (Because if it's just on your period, unlikely to be endometriosis). What symptoms does she have during your period? And if she has symptoms not on your period
- what are they? Is the pain worse on or off period.
Sne may have 1. Primary dysmenorrhea (heavy bleeding and painful periods with no condition or cause or 2. Secondary dysmenorrhea is a condition, e.g, endometriosis or adenomyosis, causing it. You will need to try NSAIDs and mirena/pill and Tranexamic acid first before any further scans like ultrasound and MRI. Often, if the pain is significantly reduced with said treatments, it's more likely (not 100%) to be primary dysmenorrhea. Also very dependant on whether you only have symptoms on your period or across the month as to whether you have primary or secondary.
Then, if ultrasounds pick up on anything (pelvic ultrasound or transvaginal), you may need to have an MRI to see endometriosis. However, the only way for definite diagnosis is a laparoscopy, and then they will often excise the endometriosis tissue if they find it, etc.
But endometriosis is a chronic illness and can not be cured. After surgery, it will grow back, it cannot be excised from everywhere to leave organ functioning intact, and then post-surgery adhesions often form.
The main symptom of endometriosis is not actually period pain because endo is not a period condition - it's a whole body inflammatory condition where the endometriosis tissue even produces its own oestrogen and the pain is felt throughout the month not just when on your period. Often, endometriosis on the ovaries can form cysts containing old blood called endometriomas (also known as chocolate cysts), which can be very painful. Another popular cyst is haemorrhagic ovarian cysts with endometriosis.
But you could also be adenomyosis where the lining of the womb grows into the muscle of it, but unlike endo is localised to the uterus only. Thus, symptoms are mainly a couple of days before a period and during your period. Main endo symptoms:
• Irregular or heavy periods
• Pelvic pain
• Pelvic pain on opening bowels (dyschesia) and wider gastrointestinal symptoms (diarrhoea and constipation)
• Pelvic pain on passing urine (dysuria) and bladder symptoms sometimes
• Referred pain to the tops of the legs or back
• Fatigue
Crucially you can still have endo even if they don't see it on the scan, the only clear way for diagnosis is a diagnostic laparoscopy and then mangagement can look like pain medication depending on how severe your pain and symptoms are (can be opioids, NSAIDs) and contraception and hormonal treatments (gonadotrophin releasing hormones).
The links below have much more detailed and useful information.
https://www.leedsth.nhs.uk/patients/resources/endometriosis-2/
https://www.nhs.uk/conditions/adenomyosis/