What is endometriosis, and how is it diagnosed and treated?

Understanding Endometriosis: Patient Explanation, Diagnosis, and Treatment

What is Endometriosis?

Endometriosis is an inflammatory disease where tissue similar to the lining of your uterus grows outside the uterus, causing chronic pain and potentially affecting your ability to get pregnant. 1, 2

Key Points to Explain to Patients:

• This condition affects approximately 10% of women during their reproductive years—about 9 million women in the US alone 3
• The tissue behaves like normal uterine lining, responding to hormones and bleeding during your menstrual cycle, but because it's trapped outside the uterus, it causes inflammation, scarring, and pain 4
• This is a systemic disease, not just a pelvic problem—it affects your entire body, including metabolism, causes body-wide inflammation, and can alter brain chemistry leading to pain sensitization and mood changes 5
• The economic burden is substantial at $69.4 billion annually, comparable to diabetes and rheumatoid arthritis 2

Clinical Presentation:

• 90% of patients experience pelvic pain, including painful periods (dysmenorrhea), pain between periods, and pain during intercourse (dyspareunia) 3
• 26% experience infertility, with approximately 50% of endometriosis patients having difficulty conceiving 2, 3
• Painful urination (dysuria) is common 2
• Some women have no symptoms at all, while others have severe symptoms that significantly impact daily life 2

Diagnosis

Diagnosis is often significantly delayed—averaging 5 to 12 years after symptoms begin, with most women seeing 3 or more doctors before getting diagnosed. 3

Diagnostic Approach:

• Clinical diagnosis can be made based on symptoms alone, supported by physical examination and imaging 3
• Normal physical examination and imaging do NOT rule out endometriosis 3
• Transvaginal ultrasound is useful for identifying and mapping deep endometriosis (lesions extending deeper than 5 mm under the peritoneal surface) 1, 2
• Pelvic MRI can provide additional imaging information 3
• Surgical visualization (laparoscopy) provides definitive diagnosis but is not required to start treatment 3

Deep Endometriosis Definition:

Deep endometriosis involves lesions extending deeper than 5 mm under the peritoneal surface or affecting the bowel, bladder, ureter, or vagina 1, 2

Treatment Algorithm

First-Line Treatment (Start Here for All Symptomatic Patients Not Seeking Immediate Pregnancy):

Hormonal suppression with combined oral contraceptives (birth control pills) or progestin-only options should be offered first. 6, 3

• NSAIDs at appropriate doses and schedules for immediate pain relief 6
• Continuous oral contraceptive pills are as effective as more aggressive treatments (GnRH agonists) but with far fewer side effects, lower cost, and better tolerability 6
• Progestins are equally effective alternatives 6
• These medications reduce pain by 13-17 points on a 0-100 pain scale compared to placebo 3

Important caveat: 11-19% of patients have no pain reduction with hormonal medications, and 25-34% experience recurrent pain within 12 months of stopping treatment 3

Second-Line Treatment (When First-Line Fails or is Contraindicated):

GnRH agonists for at least 3 months provide significant pain relief 6

• When using GnRH agonists long-term, add-back therapy (low-dose hormones) should be implemented to prevent bone loss without reducing pain relief 6
• Oral GnRH antagonists are newer alternatives with fewer side effects than older therapies 5

Third-Line Treatment:

Aromatase inhibitors 3

Surgical Treatment:

Surgical excision by a specialist is the definitive treatment and should be considered when hormonal therapies are ineffective or contraindicated. 6, 3

• Laparoscopic removal of lesions is the standard surgical approach 3
• Preoperative imaging reduces complications by decreasing incomplete surgeries and need for repeat procedures 6
• Up to 44% of women experience symptom recurrence within one year after surgery 6
• Approximately 25% of patients who undergo surgery experience recurrent pain and 10% require additional procedures 3

Definitive Treatment (For Completed Childbearing):

Hysterectomy with bilateral salpingo-oophorectomy (removal of uterus, tubes, and ovaries) plus removal of all visible endometriosis lesions 6, 3

• This is definitive treatment for appropriate candidates who have completed childbearing 6
• However, approximately 25% still experience recurrent pelvic pain and 10% undergo additional surgery 3
• Hormone replacement therapy with estrogen is not contraindicated after this surgery for endometriosis 6

Common Pitfalls to Avoid:

• Do not delay treatment waiting for surgical confirmation—start hormonal therapy based on clinical suspicion 3
• Do not assume normal imaging rules out endometriosis 3
• Do not use GnRH agonists long-term without add-back therapy due to bone loss risk 6
• Recognize that progesterone resistance occurs in about one-third of patients, explaining why first-line treatments fail 5
• Understand this is a chronic disease requiring long-term management, not a condition that can be quickly cured 5, 7