Endometriosis

Endometriosis is a condition in which tissue similar to the lining of the uterus (endometrium) grows outside the uterus — commonly on the ovaries, fallopian tubes, pelvic peritoneum, and sometimes more distant sites. These deposits respond to hormonal cycles, causing inflammation, scarring, and adhesions.

Endometriosis is a major cause of pelvic pain and infertility. Severity of symptoms does not always match the extent of disease seen at surgery. Although there is no permanent cure short of removing all reproductive organs (and even then residual disease can persist), many treatments effectively control pain and can improve fertility prospects.

Common symptoms include:

• Painful periods (dysmenorrhea) that may worsen over time
• Chronic pelvic pain outside of menses
• Pain during or after intercourse (dyspareunia)
• Pain with bowel movements or urination, especially during menses
• Heavy menstrual bleeding or bleeding between periods
• Infertility
• Fatigue, bloating, nausea, and digestive symptoms that may be mistaken for IBS

Some people with significant endometriosis have few symptoms; others with minimal visible disease have severe pain.

The exact cause is unknown. Leading theories include:

• Retrograde menstruation — menstrual blood flows backward through the fallopian tubes into the pelvis
• Cellular metaplasia — cells outside the uterus transform into endometrium-like cells
• Lymphatic or blood-borne spread of endometrial cells
• Immune-system factors that allow implants to persist
• Genetic predisposition
• Embryonic cell rest theories

Hormones, especially estrogen, fuel the growth and activity of implants.

Risk factors include:

• Never giving birth
• Starting periods at an early age or menopause at an older age
• Short menstrual cycles or heavy, prolonged periods
• Higher estrogen exposure
• Low body mass index
• Family history of endometriosis (first-degree relative)
• Reproductive tract anomalies that obstruct menstrual outflow

Complications can include:

• Infertility — distorted anatomy, inflammation, and impaired egg/sperm/embryo function
• Ovarian endometriomas (“chocolate cysts”)
• Adhesions and chronic pelvic pain
• Increased risk of certain ovarian cancers (clear cell and endometrioid) — absolute risk remains low
• Impact on quality of life, work, relationships, and mental health

Endometriosis cannot be reliably prevented. Lowering lifetime estrogen exposure (e.g., more pregnancies, longer breastfeeding, combined hormonal contraceptives in some studies) is associated with lower risk, but these are personal choices rather than formal prevention strategies. Early treatment of symptoms can limit progression of pain and scarring.

Evaluation includes:

• Detailed history of pain, menstrual pattern, and fertility goals
• Pelvic examination — may reveal tenderness, nodules, or fixed organs
• Transvaginal ultrasound — useful for endometriomas and deep disease in experienced hands
• MRI for complex or deep infiltrating disease planning
• Laparoscopy with biopsy — definitive diagnosis and can be therapeutic (excision/ablation) at the same time

Empiric medical therapy is sometimes started based on clinical suspicion without immediate surgery, especially when fertility is not an urgent concern.

See a healthcare professional for severe period pain that interferes with school, work, or daily life; pain with sex; difficulty conceiving after 6–12 months of trying; or pelvic pain that does not improve with simple measures. Early evaluation can reduce years of unnecessary suffering.

Treatment is individualized according to symptoms, extent of disease, and desire for fertility:

Pain management

• NSAIDs
• Continuous combined hormonal contraceptives or progestin-only methods (pills, implant, injection, LNG-IUD)
• GnRH agonists or antagonists with add-back therapy
• Aromatase inhibitors in selected refractory cases
• Neuromodulators and pelvic-floor physical therapy for central sensitization and muscle contributions

Surgery

• Laparoscopic excision or ablation of implants and adhesiolysis
• Removal of endometriomas with attention to ovarian reserve
• Hysterectomy ± removal of ovaries in selected people who have completed childbearing and have severe, refractory disease

Fertility

• Surgical restoration of anatomy when appropriate
• Assisted reproductive technology (IVF) — often effective and may be preferred over repeated surgery

Helpful measures include:

• Heat therapy and appropriate use of NSAIDs for flares
• Regular physical activity and pelvic-floor physiotherapy when indicated
• Stress management and psychological support
• Tracking symptoms and cycles to guide treatment discussions
• Discussing fertility goals early with the care team
• Joining reputable endometriosis support communities

Bring:

• Symptom diary (pain timing relative to menses, intercourse, bowel/bladder symptoms)
• Menstrual and obstetric history
• Previous treatments and surgeries
• Fertility goals and timeline
• Questions about medical vs surgical options and expected outcomes