Overview
Endometriosis is a condition where tissue similar to the lining of the uterus grows outside the uterus, commonly on the ovaries, fallopian tubes, and pelvic tissues. Each month this tissue responds to hormonal changes, causing inflammation, pain, and scarring. It is a significant cause of period pain, chronic pelvic pain, and infertility.
How common is it?
Endometriosis affects around 1 in 10 women of reproductive age worldwide, equivalent to approximately 1.5 million women in the UK.
Causes and risk factors
The exact cause is not fully understood. The most accepted theory involves retrograde menstruation, where menstrual blood flows backwards through the fallopian tubes into the pelvis. Genetic and immune factors also play a role.
Common risk factors
- Family history of endometriosis
- Starting periods early or having long or heavy periods
- Having a shorter than normal menstrual cycle
- Never having been pregnant
- Immune system abnormalities preventing clearance of misplaced tissue
Symptoms
- Very painful periods (dysmenorrhoea)
- Chronic pelvic pain between periods
- Pain during or after sexual intercourse
- Painful bowel movements or urination, particularly during periods
- Heavy menstrual bleeding
- Difficulty becoming pregnant
- Fatigue
- Some women have no symptoms at all
When to see a doctor
See a doctor if period pain is severe enough to interfere with daily life, pain during sex is a problem, or you are having difficulty conceiving.
Diagnosis
Laparoscopy (keyhole surgery) is the only definitive diagnostic test and allows simultaneous treatment. Ultrasound can identify ovarian endometrioma (chocolate cysts) and deep disease. MRI provides additional information before surgery.
Treatments
Hormonal therapy
Combined oral contraceptive pill, progestogens, and the Mirena IUS suppress ovulation and endometrial growth, reducing pain. These manage symptoms but do not cure the condition.
Surgery
Laparoscopic excision or ablation of endometriotic deposits is more effective than hormone treatment for pain. Specialist centres offer surgery for severe disease.
Analgesics and NSAIDs
Ibuprofen and naproxen taken regularly around the menstrual period reduce pain by inhibiting prostaglandin production.
Self-care and lifestyle
- Heating pads provide symptomatic relief during painful periods
- Regular exercise may reduce symptoms by lowering oestrogen levels
- A low-inflammatory diet (reduced red meat, processed food) may modestly help some women
- Psychological support and pain management therapy help with chronic pain
Prevention
There is no known way to prevent endometriosis. Earlier diagnosis and treatment reduce the impact on fertility and quality of life.