Endometriosis Stages: Determination and Significance

Does the pain caused by endometriosis sometimes bring you to your knees? Does this mean you are in stage 3 or 4 of endometriosis? Not necessarily. Let's take a closer look at how the stages of endometriosis are classified.

The Most Common Classification Method for Endometriosis: The ASRM Points System

Most doctors use the numerical scale system created by the American Society for Reproductive Medicine (ASRM) to evaluate the different stages of endometriosis. The stages range from 1 to 4 and are determined by assigning points based on the characteristics of the disease.

Other methods that can be used to determine the stages of endometriosis include:

• ENZIAN Classification System - This is used to supplement the ASRM system and uses MRI to assess the severity of invasiveness.
• Endometriosis Fertility Index (EFI) - This scale was developed to predict the fertility rate of patients with endometriosis.
• Descriptive Categories from the Endometriosis Foundation of America - These classify the disease based on its anatomical location.

How are endometriosis points assigned?

Since endometriosis usually does not appear on diagnostic scans like a CT or ultrasound, the only way for a doctor to officially confirm the diagnosis is to perform surgery for endometriosis and look inside the abdomen and pelvis.

While examining the lesions, the doctor will note things like appearance, depth, and color. Then they will assign points based on these characteristics to determine the patient's stage of endometriosis.

Stage 1 Endometriosis: Minimal

Endometriosis that scores from 1 to 5 points on the ASRM scale is classified as stage 1, or minimal. Stage 1 is used to describe cases where:

• The endometrial growths are few, small, and superficial
• The growths appear on organs or the tissue lining the abdominal and pelvic cavities
• Scar tissue is non-existent or minimal

As mentioned earlier, stage 1 endometriosis does not mean the patient will not have symptoms or that the disease will not significantly impact daily life.

Stage 2 Endometriosis: Mild

Endometriosis that scores from 6 to 15 points on the ASRM scale is classified as stage 2, or mild. Stage 2 is used to describe cases where:

• There are more endometriosis implants than in stage 1
• The implants are deeper than in stage 1
• Scar tissue may be present, but there are no signs of active inflammation

Stage 3 Endometriosis: Moderate

Endometriosis that scores from 16 to 40 points on the ASRM scale is classified as stage 3, or moderate. Stage 3 is used to describe cases where:

• There are many deep endometrial implants
• There are cysts (ovarian endometriomas) on or in at least one ovary
• Thin adhesions may be present

This is the first stage where adhesions are present. Adhesions often cause organs to stick together, which can lead to sharp and piercing pain. Adhesions can also cause other problems, such as gastrointestinal issues like nausea when they are on the intestines or make it harder to conceive when they appear on reproductive organs.

Stage 4 Endometriosis: Severe

Endometriosis that scores more than 40 points on the ASRM scale is classified as stage 4, or severe. Stage 4 is used to describe cases where:

• Adhesions are extreme
• There are many cysts

Some ovarian cysts can disappear on their own, but those formed due to endometriosis usually require surgical removal. These cysts have been known to grow to the size of a grapefruit. There may also be small cysts on the back wall of the uterus and rectum in stage 4 endometriosis, which can lead to:

• Abdominal pain
• Nausea
• Vomiting
• Constipation
• Painful bowel movements

If lesions, scar tissue, or cysts block one or both fallopian tubes, they can cause infertility. Despite stage 4 endometriosis being the most severe, some women have it and the only symptom they experience is difficulty conceiving.

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