Written by Babatunde Carew
Spoon Feed
This review outlines the epidemiology, diagnosis, and treatment of endometriosis.
Endometriosis in focus – a clinical review for primary care
Endometriosis is a chronic, estrogen-dependent inflammatory condition associated with pelvic pain and infertility that affects ~10% of women worldwide (~9 million in the U.S.). It can significantly reduce quality of life and increase the risk of comorbidities such as depression, fatigue, and, in some cases, ovarian cancer. Despite its prevalence, diagnosis is frequently delayed.
Epidemiology
- Affects ~10% of reproductive-age women globally (~9 million in the U.S.).
- Associated with $78 billion in annual U.S. costs (medical + lost productivity).
- Risk factors include: Early menarche (<12 years), short menstrual cycles (<28 days), low BMI, nulliparity, congenital obstructive müllerian anomalies, family history (RR 5.2 for sisters)
Endometriosis subtypes
- Superficial peritoneal – Lesions on the serosa of pelvic/abdominal organs.
- Deep endometriosis – Infiltrates pelvic peritoneal surface or muscularis of pelvic organs (e.g., bladder, bowel).
- Ovarian (endometriomas) – Blood-filled cysts (a.k.a. “chocolate cysts”).
- Extrapelvic – Rare; may affect diaphragm, lungs, abdominal wall, even brain.
Pathophysiology
- Retrograde menstruation is widely accepted as a key contributor; lymphatic or vascular metastasis has also been proposed as a potential mechanism for the development of extrapelvic lesions.
- Lesions depend on estradiol to proliferate and persist.
- Cause of pain is likely multifactorial. Nociceptive: inflammatory pain from local irritation; Neuropathic: nerve invasion or sensitization; Nociplastic: central sensitization → widespread pain, fatigue, poor sleep.
- Infertility mechanisms include adhesions, tubal blockage, ovarian dysfunction, and uterine environment changes.
Clinical presentation and clinical course
- 90% report pelvic pain (dysmenorrhea, non-menstrual pain, deep dyspareunia).
- 26% experience infertility.
- Pain severity does not correlate with lesion burden (except deep lesions → dyspareunia).
- Symptoms are often catamenial (worsen during menstruation); extrapelvic lesions cause site-specific cyclic symptoms.
- Most symptoms improve post-menopause, though some persist or appear de novo with hormone therapy.
Assessment and diagnosis
- Diagnosis is clinical: based on history, supported by pelvic exam and imaging.
- Pelvic exam may reveal nodularity, decreased uterine mobility, or adnexal mass (endometrioma).
- Imaging – No imaging modality has 100% sensitivity, so the absence of findings on imaging does not rule out endometriosis.
- Transvaginal ultrasound: good for endometriomas and deep lesions (low sensitivity for superficial).
- MRI with endometriosis protocol: useful for deep and extrapelvic disease.
- Augmented ultrasound (not widely used in U.S.) enhances detection.
- Definitive diagnosis via laparoscopic visualization/biopsy, but guidelines support clinical diagnosis to reduce delays.
Treatment
- First-line: Hormonal suppression for patients not seeking pregnancy
- Combined estrogen-progestin contraceptives (prefer continuous use)
- Progestin-only options (oral, IUD, injection, implant)
- Second-line: GnRH agonists/antagonists (with add-back therapy to reduce hypoestrogenic effects).
- Third-line: Aromatase inhibitors
- Surgical options:
- Laparoscopic lesion removal if medical therapy fails.
- Hysterectomy for refractory cases (but ~25% have recurrent pain, and 10% need repeat surgery such as lysis of adhesions).
- Adjunct therapies: pelvic floor PT, CBT for chronic pain, and management of overlapping conditions (e.g., IBS, interstitial cystitis).
Source
Endometriosis: A Review. JAMA. 2025 May 5. doi: 10.1001/jama.2025.2975. Epub ahead of print. PMID: 40323608
