Endometriosis

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This tool is designed to support primary care clinicians in assessing, diagnosing and implementing treatment for people with endometriosis. Endometriosis is an inflammatory condition with growth of endometrial tissue outside the uterus. This can cause chronic, painful symptoms and infertility. Up to 10% of Canadian women are impacted by this disease. An unknown number of gender-diverse individuals are affected by endometriosis. Only 7% of Canadian women have been diagnosed with endometriosis and there can be considerable diagnostic delay for people with this condition (an average of 7-10 years). Delayed diagnosis can have a significant impact on mental health, trust in the patient-clinician relationship, and participation in daily activities such as work or school.³

For a high-level overview of the diagnosis and management of endometriosis, see the algorithm below:

Endometriosis overview algorithm^1-6

Endometriosis-algorithm_03.31.2026.pdf

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Assessment New

Initial assessment^1-5

Consider endometriosis in individuals, including adolescents, presenting with the following symptoms and risk factors:

Symptoms

Can include:

Chronic pelvic pain (> 3 months)
Common symptom cluster
- Dysmenorrhea (pain associated with menstruation)
- Dyspareunia (pain during or after intercourse)
- Dyschezia (painful bowel movements)
- Dysuria (pain passing urine)
Infertility
Systems-related symptoms, often with exacerbation related to menstruation:
- Genital tract: post-coital bleeding
- Urinary tract: hematuria, flank pain 
- Gastrointestinal: bloating, diarrhea, constipation, obstructive symptoms (nausea/emesis), painful rectal bleeding
- Diaphragm/chest: Shoulder pain or subcostal pain. Rare: pneumothorax, hemothorax, cyclical cough/haemoptysis/chest pain
- Skin, muscle, fascia: painful mass with catamenial exacerbation at site of previous incisions (rare)
- Nerve involvement: sciatica

Risk factors

Can include:

First-degree relatives with a history or symptoms of endometriosis
Obstructive mullerian malformations
Early menarche (<10 to 12 years)
Short menstrual cycle (<26 to 26-31 days)
Lower body mass index
Nulliparity

Practice points^1-5:

Routinely validate patient experiences by acknowledging the psychological and social impacts of endometriosis (e.g., chronic stress, fear of infertility, and disruption to daily activities) and recognize that some individuals may have had prior negative healthcare experiences requiring a trust-building, trauma-informed approach. Distinguish between symptoms of endometriosis and non-specific secondary symptoms and investigate the root cause of pain rather than normalizing symptoms (e.g., severe menstrual pain) to help prevent delays in diagnosis.
Individuals with endometriosis may have a slightly increased risk of ovarian cancer, but the absolute risks remain low. No additional cancer screening beyond routine screening guidelines is recommended.

Diagnosis^1-7

Use a patient-centered care approach to diagnosing endometriosis, which involves acknowledging and believing the individual’s reported experiences and symptoms. Care should be trauma-informed and sensitive to the needs of diverse populations. Use empathic communication to help individuals feel safe and supported when discussing their symptoms. Consider factors such as symptom impact, fertility desires, and cultural background.

Clinical diagnosis

Perform a complete history including:
- Symptoms
- Medical history (e.g., medications, previous therapies/treatments, surgical history, autoimmune diseases)
- Previous investigations (e.g., recent ultrasound, HPV test or MRI)
- Family history
- Impact on quality of life and activities of daily living (ADL)
Perform an abdominal and pelvic examination (e.g., vaginal or bimanual exam) to identify physical signs of endometriosis.
- Palpate for tenderness, pain, stiffness, abnormalities and nodularity.
- Potential benefits of a pelvic examination should be balanced against possible patient discomfort.
- See UofT’s Pelvic examination videos for more information.
Evaluate the degree and localization of pain.
A normal examination does not exclude the possible diagnosis of endometriosis or the need for further investigation. Continue with imaging diagnosis if symptoms are consistent with endometriosis.

Imaging diagnosis

Based on history and physical examination, imaging may be required to confirm and clarify the diagnosis and show extent of disease.

Basic ultrasounds: A basic transvaginal ultrasound is the first-line imaging modality for suspected endometriosis. If this scan is declined or not appropriate for the individual, a basic transabdominal ultrasound can be used. These ultrasounds assess the uterus, ovaries and rectouterine pouch for fluid or masses. Basic ultrasounds can be used to detect ovarian endometriomas and rule out endometriosis pathologies like fibroids, but cannot detect superficial or deep endometriosis.
Advanced ultrasounds: In addition to the basic ultrasound assessment, advanced abdominal and pelvic ultrasounds evaluate anterior components (bladder, ureters), posterior components (bowel, uterosacral ligaments, vagina, rectovaginal septum), soft markers (ovarian mobility, site-specific tenderness) and rectouterine pouch obliteration state (sliding sign), making them better equipped to detect deep endometriosis. Ensure these components are specified on the requisition form. Advanced ultrasounds for endometriosis is not widely available and typically depends on the expertise of individual sonographers at specialized centres (e.g., women’s health centres, endometriosis clinics).

Pelvic MRI: May be used when advanced ultrasound is not possible or available, or if there is a high degree of suspicion of deep endometriosis involving the bowel, bladder or ureters.

Types of endometriosis
Superficial endometriosis	Endometriotic deposits on the peritoneum.
Ovarian endometriosis	Cyst formed when endometriosis affects the ovaries (endometriomas).
Deep endometriosis	Extends beyond the peritoneum with nodular or fibrotic lesions that can involve organs (e.g., bowel, bladder, nerves).
Extrapelvic endometriosis	Extends outside of the true pelvis and reproductive organs.

Where possible, refer to imaging clinics that indicate experience with endometriosis-related imaging as diagnostic accuracy can rely on the expertise of the individual performing and interpreting the scan.
It is important to note that endometriosis cannot be completely excluded if the ultrasound or MRI is reported as normal, particularly for superficial peritoneal disease.

Surgical diagnosis

Although laparoscopy (performed by a specialist) has been considered the “gold standard” for diagnosing endometriosis, it is no longer relied upon to make a diagnosis or to initiate treatment.
A presumptive diagnosis can be made through clinical assessment and imaging, with referrals to specialists for clarification as needed.
The risks and benefits of laparoscopy must be weighed with each individual.

Practice points^1,3,5:

Gynecologic and pelvic exams can be triggering for individuals who have experienced past trauma or sexual violence. A pelvic examination may not be appropriate for those who have not been sexually active or with vaginal muscle pain. For some individuals, the sex or gender of the provider may influence comfort with the examination. Allow the individual to have a support person present.
Enhance individual comfort and reduce procedure-related anxiety by offering verbal guidance, utilizing warmed or plastic speculums of the smallest appropriate size, ensure adequate lubrication and have individuals adopt a “butterfly” position instead of invasive stirrups when appropriate.

See SOGC’s Trauma and Violence-Informed Care resource for more information.

Differential diagnosis^1,3-5

Pelvic pain from other causes (e.g., ovarian cysts, torsion)
Adhesions
Adenomyosis
Pelvic inflammatory disease (IPD)
Fibroids
IBD or IBS (abdominal pain)
Constipation
Lower abdominal pain (chronic UTIs)
Malignancy (rare)

The presence of other conditions does not rule out a potential diagnosis of endometriosis, as these may coexist and should not prevent further evaluation if symptoms are suggestive.

Biomarkers should not be used as they cannot accurately diagnose endometriosis. This includes^1-6:

Serum CA125*
Biomarkers (individual or panels) in endometrial tissue, blood, menstrual or uterine fluids

_{*CA-125 should NOT be ordered for a pre-menopausal patient with an ovarian cyst as it’s not helpful in clarifying the diagnosis and will often be elevated in endometriosis.}

Gender diverse and racialized individuals experience inequities in accessing appropriate endometriosis care which negatively affects their health outcomes. African, Caribbean, and Black individuals are less likely to receive an endometriosis diagnosis and may face more unnecessary surgical procedures or post-operative complications compared to White individuals. In Canada, a history of reported reproductive coercion contributes to a significant trust barrier for First Nations, Métis, and Inuit individuals. All individuals who experience endometriosis deserve patient-centered, evidence-based quality care.³

Referrals^1-3,5

Consider referral to specialists (e.g., gynecology, fertility, pain management) when:

Diagnosis is unclear
First line treatment is contraindicated, not tolerated or not effective
Symptoms are severe/persistent/recurrent
Individuals have related infertility
Surgery is indicated (imaging indicates ovarian endometriosis, deep endometriosis, or endometriosis outside the pelvic cavity)

Resources

Sunnybrook Expedited Endometriosis (SEE) Clinical: a virtual clinic to “SEE” if your patient has endometriosis.
Endometriosis Clinic at McMaster University: a multidisciplinary and inter-professional approach to endometriosis management.

Management New

Pharmacological management^1,2,4-6

Employ a shared decision-making approach when considering pharmacological management options. These decisions should consider the benefits and risks of each option, individual preference, co-morbid conditions, side effects, costs, and desire for fertility.

Pharmacological options

While many first-line treatments are not specifically indicated for endometriosis, they can help manage the condition and endometriosis-related symptoms.^1,2,4,6 Review first-line treatments for pain relief and tolerability after 3 months. If the previously tried treatments were ineffective or not tolerated, explore alternative options, reviewing after a trial period of another 3 months.¹ See the medications table for more information.

First-line treatment

Hormonal treatments^1,2,4,6

Combined oral contraceptives, progestogens, oral, injectable, and intrauterine systems.
All hormonal treatments show comparable efficacy for painful periods, pelvic pain and pain with intercourse.
Do not offer if fertility is a current priority. See fertility consideration section.

Simple analgesics: NSAIDs or acetaminophen^1,2,4,6

Short trial
May be offered alone or alongside other treatment options, depending on the needs and preferences of the person with endometriosis and considerations such as fertility.
May only reduce endometriosis-related pain.

If first-line treatment options have not improved symptoms or are not acceptable to the individual, seek specialist eConsult support to address second-line treatment options or refer to specialist gynecologist services. With support from specialist eConsult, primary care may be able to improve access to these medications for people with endometriosis.^1,5

Second-line treatment

GnRH agonists^1,4,6

Includes goserelin acetate, leuprolide acetate, nafarelin acetate, triptorelin pamoate.
Considered second-line treatment due to their side effect profile.
Treatment works by causing the body to release less estrogen.
See medications table for more information.

GnRH antagonists^1,4,6

Includes relugolix-estradiolnorethisterone, elagolix.
Considered second-line treatment due to their side effect profile.
Treatment works by causing the body to release less estrogen.
See medications table for more information.

Narcotics^1,5

Opioids should be considered with caution and only as a short-term solution. If pain is refractory and opioids must be considered, use only for a limited time and at the minimum.
Consider consulting a pain specialist.

Neuromodulators¹

Includes tricyclic anti-depressants, selective serotonin uptake inhibitors, anti-convulsants.
When appropriate, facilitate conversations about the benefits and risks of neuromodulators with individuals with endometriosis.
Explain that there is limited research to support their use in endometriosis management and that lower doses are used than when treating anxiety or depression.

Treatment considerations

GnRH Agonists or Antagonists and Bone Mineral Density (BMD)⁵

GnRH Agonists are used off-label for endometriosis if used for more than 6 months. They should not be used for more than 6 months because of the associated risks of reduced bone mineral density (BMD) with these agents; there is limited data about their long-term use and its impact on BMD. Some specialists, however, may consider using GnRH agonists off-label for longer than 6 months, with add-back therapy to mitigate other side effects.
Primary care physicians may seek support for prescribing these agents from a specialist through e-Consult, or work closely with their local specialist colleagues. Monitoring BMD with the use of GnRH agonists is important, along with optimization of BMD (i.e. vitamin D and calcium intake, weight-bearing exercise, falls prevention, etc). Consider a baseline BMD test before starting these agents, and follow-up testing as indicated. Individuals with endometriosis considering this option must be aware that the use of GNRH Agonists for endometriosis is off-label, and benefits and risks must be discussed collaboratively.
The same concepts with GnRH agonists apply to the GnRH antagonists in terms of BMD and appropriate monitoring, as well as specialist input if used off-label longer than their indicated time period. GnRH Antagonists are used off-label for endometriosis if used for longer than 24 months+ for Myfembree (Relugolix–estradiol–norethisterone) and 6 months for Orilissa (Elagolix).

Pharmacological management of adolescents^1,4,5

Hormonal and simple analgesic options are appropriate for adolescents. Hormonal contraceptives or progestogens are first-line hormone therapy for symptoms in adolescents such as severe dysmenorrhea and/or endometriosis-associated pain.
Be aware that some progestogens may decrease bone mineral density in adolescents.
Consider NSAIDs to relieve endometriosis-related pain, especially if first-line hormone treatment is not appropriate for the individual.
When selecting add-back therapy for bone mineral density, many clinicians consider products with moderate estrogen for adolescents.
GnRH Agonists should only be used in adolescents after careful deliberation and discussion of potential side effects and risks. Consider referral or seek specialist support for use of second-line medication, such as GnRH Agonists, in adolescents.

There is very limited evidence to support the use of Selective Estrogen Receptor Modulators (SERMS) and Aromatase inhibitors. In specific circumstances, such as in cases of pain unresponsive to other treatments, Aromatase inhibitors may be considered alongside other treatments.^1,4

Medications table

Endometriosis-Meds-Table_03.24.2026.pdf

Download

Example medication monitoring process^1,5

The prescribing and monitoring process may look different as you consider individual needs and shared decision making.

Non-pharmacological management

Individuals with endometriosis often experience impacts across physical, psychological, sexual, reproductive, and social domains. While high-quality evidence for specific non-pharmacological interventions for endometriosis management remains limited, many individuals seek these approaches to help manage pain, improve function, and cope with symptoms.^1,4,6 Pharmacological and non-pharmacological approaches may be used in combination for those seeking both options and it is important to listen to individuals’ preferences when discussing management options.⁵

Clinicians are encouraged to^1,2,4,6:

Acknowledge the role of non-pharmacological strategies while clarifying that no specific intervention currently has strong evidence for reducing endometriosis-related pain, but they may support general well-being.

Discuss practical considerations, including variable availability, potential out-of-pocket costs, limited treatment details, and the possibility of adverse effects.

Promote access to reputable support resources, including local or online support groups, which may provide education*, coping strategies, and community connection. See patient resources in follow-up & monitoring. Employ a shared decision-making approach when considering pharmacological management options. These decisions should consider the benefits and risks of each option, individual preference, co-morbid conditions, side effects, costs, and desire for fertility.

_{*Consider the importance of health literacy and the abundance of misleading information online.}

The following interventions may be considered according to individual preference, symptom severity and clinical judgment:

Non-pharmacological management options

Physiotherapy¹

Examples: Manual therapy such as soft tissue techniques and manipulation; pelvic floor physiotherapy such as Thiele massage. See patient resources below.
May improve pelvic pain and pain with intercourse.

Psychological interventions¹

Examples: Psychotherapy with somatosensory stimulation (acupuncture, moxibustion and heat), mindfulness, counselling. See patient resources below.
May make small improvements in pelvic pain and quality of life.

Acupuncture¹

May make short-term improvements in endometriosis-related pain and quality of life.
Advise that there is limited evidence for the effectiveness of other complementary/alternative approaches in pain management.

Dietary approaches¹

Examples: FODMAP diet, dietary supplements such as fish oil and vitamin D.
Limited evidence, but some may find associations with pain.

Physical activity^5,9-11

Examples: Breathing exercises, yoga, muscle relaxation, and walking.
Limited evidence but physical activity may:
- Provide pain relief
- Improve quality of life
- Enhance overall health by reducing stress and improving mood
- Help mitigate side effects from pharmacological therapies.

Practice point: Discuss use of medicinal cannabis and non-prescribed cannabis due to common use. No specific recommendations can be made due to limited evidence for potential benefits and risks of its use.¹

Patient resources

Complementary and Alternative Medicine: A Guide for People With Endometriosis (The Endometriosis Network Canada)
Pelvic Health Physiotherapy 101 (The Endometriosis Network Canada)
Kegel Exercises (Health Link BC)
Mental Health, Well-Being and Quality of Life; A Guide for People with Endometriosis and Those Who Support them (The Endometriosis Network Canada)
Ontario Structured Psychotherapy Program (Ontario Health)
Bounce Back Ontario

Fertility considerations^1-6

Consider pregnancy intentions when selecting treatment, as endometriosis can affect fertility (with approximately 10-30% of individuals experiencing infertility) and hormonal contraceptives are first-line treatments options. Management differs for individuals with short-term fertility goals (actively trying to conceive) versus long-term fertility goals (future pregnancy desired but not currently trying to conceive).

Treatment options

Hormonal therapy

Actively trying to conceive: Do not offer hormonal therapy (e.g., ovarian suppression treatment), alone or combined with surgery, as it does not improve unassisted pregnancy rates.
Not actively trying to conceive: Hormonal treatments are unlikely to be detrimental to future fertility goals.

Non-pharmacological management

Non-pharmacological strategies (e.g., psychological interventions, diet, physical activity, etc.) may support general well-being but do not improve fertility outcomes in individuals with endometriosis-associated infertility.
See non-pharmacological management section.

Surgical treatment

Surgical treatments are unlikely to negatively impact future fertility; however, surgery is generally reserved for individuals whose symptoms are refractory to first- and second-line treatments, or for select cases where endometriosis is significantly affecting fertility. In some individuals with severe, medication-refractory pain, surgery may also improve physical, emotional, and psychological well-being, which can indirectly support fertility-related goals.
It is important to note that in individuals trying to conceive, surgical options and associated wait-times or stressors may inadvertently cause delays in pregnancy-related plans.
The decision to pursue surgery should consider the presence or absence of pain symptoms and symptom severity, age, disease type, individual preferences, surgical history, infertility factors and ovarian reserve through shared decision-making.

Practice point: Management of endometriosis-related infertility should involve a multidisciplinary team, including a fertility specialist. Referral to a fertility specialist is recommended if fertility is a priority.^1,2

For those with infertility, do not prescribe pentoxifylline, other anti-inflammatory drugs or letrozole outside of ovulation-induction to improve pregnancy rates.⁴

Follow-up & monitoring New

Endometriosis can be a chronic condition with ongoing physical, sexual, psychological, and social impacts. Effective management of endometriosis involves follow-up and ongoing monitoring to ensure treatment plans are optimized and should be tailored to the individual’s symptoms, prior treatments, goals, and disease severity. Care coordination across relevant specialties is essential to address the impacts of endometriosis and optimize outcomes.^1,2,4,5

Follow-up schedule

Schedule follow-up visits after multiple menstrual cycles or ~3 months when initiating or modifying treatment. Consider transitioning to annual visits once individuals are stable and routinely assess quality of life and fertility status.

Symptoms review

Review changes in symptoms, side effects, pain, treatment management and impact on daily living.

Pharmacological treatment review

Hormonal therapy: Reassess first-line hormonal treatments after 1, 3 and 6 months. If ineffective or not tolerated, consider alternative first-line options or referral. See example medication monitoring process.
Analgesics/neuromodulators: Monitor for effectiveness, side effects, and co-occurring conditions.
Adolescents: Monitor response to hormonal therapy or analgesics, considering bone health and growth.
Fertility considerations: Ensure treatment aligns with pregnancy intentions and adjust monitoring if priorities change.

Non-pharmacological treatment review

Monitor non-pharmacological management plans by assessing the need for pelvic physiotherapy and psychological therapy to ensure they align with an individual’s progress and preferences. See non-pharmacological management section.

Referral considerations

Non-response to first-line therapies
Severe or progressive symptoms
Development of complications (e.g., endometrioma, deep endometriosis involving the bowel, bladder, or ureter, fertility)

Resources

Clinician resources

Your Endometriosis Hub (The Endometriosis Network of Canada)
Endometriosis (SOGC)
SF-36 questionnaire

Patient resources

YourPeriod.ca (SOGC)
Pain Logbook (SOGC)
Pain and Symptom Diary (Endometriosis UK)
Pelvic Pain/Endometriosis (BC Women’s Hospital and Healthcare Centre)
Your Endometriosis Hub (The Endometriosis Network of Canada)
External Support and Resources (The Endometriosis Network of Canada)
Virtual Support Groups (The Endometriosis Network of Canada)
Medical Treatment Options (Gynecology Quality Improvement Collaboration)

References

Note: This list excludes most medication-related references, which are listed in the medications table. Some references may appear in both lists where applicable.

[1]

The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Australian Living Evidence Guideline: Endometriosis. 2025.
[2]

National Institute for Health and Care Excellence (NICE). Endometriosis: diagnosis and management. 2024.
[3]

Singh SS, Allaire C, Al-Nourhji O, Bougie O, Bridge-Cook P, Duigenan S, et al. Guideline No. 449: Diagnosis and Impact of Endometriosis – A Canadian Guideline. J Obstet Gynaecol Can. 20240328th ed. 2024 May;46(5):102450.
[4]

ESHRE Endometriosis Guideline Development Group. Endometriosis: Guideline of European Society of Human  Reproduction and Embryology. 2022.
[5]

Expert opinion.
[6]

DeMaio A McTiernan, A, Durand O’ Connor A, Reidy F, O’ Neill, A. National Clinical Practice Guideline: Assessment and Management of Endometriosis. National Women and Infants Health Programme and The Institute of Obstetricians and Gynaecologists. 2025.
[7]

Robstad N, Paulsen A, Vistad I, Hott AC, Hansen Berg K, Øgård-Repål A, et al. Experiences of pain communication in endometriosis: A meta-synthesis. Acta Obstet Gynecol Scand. 20241023rd ed. 2025 Jan;104(1):39–54.
[8]

The Faculty of Sexual and Reproductive Healthcare. FSRH Guideline: Combined Hormonal Contraception [Internet]. 2023.
[9]

Xie M, Qing X, Huang H, Zhang L, Tu Q, Guo H, et al. The effectiveness and safety of physical activity and exercise on women with endometriosis: A systematic review and meta-analysis. PLoS One. 20250213th ed. 2025;20(2):e0317820.
[10]

Afreen S, Perthiani A, Sangster E, Lanka N, Acharya P, Virani S, et al. Comparing Surgical, Acupuncture, and Exercise Interventions for Improving the Quality of Life in Women With Endometriosis: A Systematic Review. Cureus. 20240724th ed. 2024 Jul;16(7):e65257.
[11]

Mazur-Bialy A, Tim S, Pępek A, Skotniczna K, Naprawa G. Holistic Approaches in Endometriosis – as an Effective Method of Supporting Traditional Treatment: A Systematic Search and Narrative Review. Reprod Sci. 20240723rd ed. 2024 Nov;31(11):3257–74.

Acknowledgement and legal

The Endometriosis tool was developed using the Centre for Effective Practice’s (CEP’s) integrated knowledge translation approach as part of the Knowledge Translation in Primary Care (KTinPC) Initiative. This approach ensures that clinicians are engaged throughout the development processes through the application of user-centered design methodology. Clinical leadership of the resource was provided by Dr. Marina Abdel Malak. End users and clinical experts were also engaged to provide feedback. Funded by the Ministry of Health, the KTinPC Initiative supports primary care clinicians with a series of clinical tools and health information resources. Learn more about the KTinPC Initiative.

This Tool was developed for licensed health care professionals in Ontario as a guide only and does not constitute medical or other professional advice. Health care professionals are required to exercise their own clinical judgement in using this tool. Neither the CEP, Government of Ontario, nor any of their respective agents, appointees, directors, officers, employees, contractors, members or volunteers: (i) are providing medical, diagnostic or treatment services through this Tool; (ii) to the extent permitted by applicable law, accept any responsibility for the use or misuse of this Tool by any individual including, but not limited to, primary care providers or entity, including for any loss, damage or injury (including death) arising from or in connection with the use of this Tool, in whole or in part; or (iii) give or make any representation, warranty or endorsement of any external sources referenced in this Tool (whether specifically named or not) that are owned or operated by their parties, including any information or advice contained therein.

This Tool is a product of the CEP. Permission to use, copy, and distribute this material for non-commercial and research purposes is granted, provided that the above disclaimer, this paragraph and the following paragraphs, and appropriate citations appear in all copies, modifications and distributions. Use of automated systems and tools, including but not limited to web crawlers, spiders, data scrapers or artificial intelligence agents, to extract, reproduce, or repurpose any content in this Tool is strictly prohibited without prior written consent from the CEP. Use of this Tool for commercial purposes, any modification of the Tool, or any automated or large-scale reproduction or extraction is subject to charge and must be negotiated with the CEP (info@cep.health).

For statistical and bibliographic purposes, please notify the CEP (info@cep.health) of any use or reprinting of the Tool. Please use the following citation when referencing the Tool: Reprinted with Permission from Centre for Effective Practice. (April 2026). Endometriosis: Ontario. Toronto: Centre for Effective Practice.

Developed by:

Endometriosis

Endometriosis overview algorithm^1-6