Date amended:
Statements of Principles
Current RMA Instruments
Reasonable Hypothesis SOP
51 of 2021
Balance of Probabilities SOP
52 of 2021
Changes from previous Instruments


ICD Coding
  • ICD-9-CM Codes: 617
  • ICD-10-AM Codes: N80
Brief description

The endometrium is the inner layer of the uterus. Endometriosis is the presence of endometrial glands and stroma outside of the uterus.  Endometriosis usually occurs in the pelvis but can involve other sites such as the bowel, diaphragm and pleural cavity.  Symptoms can range from minimal to severe and typically include pelvic pain (including dysmenorrhea and dyspareunia).

Confirming the diagnosis

Definitive diagnosis requires histologic evaluation of a lesion biopsied during surgery (e.g. laparoscopy). A presumptive diagnosis can be based on symptoms, clinical examination and imaging findings.

The relevant medical specialist is a gynaecologist.

Additional diagnoses covered by SOP
  • Endometrioma 
Conditions excluded from SOP
  • Adenomyosis (endometrial tissue within the muscular wall of the uterus)
  • Ectopic endometrial tissue that has not resulted in clinical manifestations and has not required treatment.
Clinical onset

The condition usually manifests during reproductive years (peak prevalence age 25 to 35), with onset of pelvic pain.  The pain may be related to menstruation, or chronic. There can be a wide range of associated symptoms.  Other presentations can include an ovarian mass, or infertility.  The condition may also be found incidentally on imaging or at surgery.  The condition needs to be clinically apparent (with symptoms or signs) or require treatment for the SOP to apply. Occassionally the condition may first present in postmenopausal women.  

Clinical worsening

Assessment of worsening would be based on an increase in clinical manifestations, or imaging/surgical evidence of more widespread or severe disease.