If you’ve been diagnosed with endometriosis, you’re likely familiar with the confusing and frustrating aspects of the condition. You might be wondering, “How many stages of endometriosis are there?” or “How do I know what stage of endometriosis I have?”

The American Society of Reproductive Medicine (ASRM) has classified endometriosis into four stages. Some organizations also recognize a fifth stage called deep-infiltrating endometriosis. The ASRM has also created a point system to help classify the stages of the disease.

The stage of endometriosis doesn’t reflect the symptoms you experience, such as pain, infertility, or other symptoms. It’s based on a doctor’s observation of damage during diagnosis. For example, a person with stage 1 endometriosis can experience severe pain, while someone with stage 4 may notice little or no pain.

Most people with endometriosis have stage 1 or 2. Endometriosis can progress over time, especially if you do not get treatment.

The stage of endometriosis is based on the amount, size, depth, and location of the endometrial implants (misplaced uterine tissue). The stage is assessed based on how far the endometrial tissue has spread in the pelvic cavity, which organs and structures have been affected, how many adhesions (tissue sticking to nearby organs) are present, and whether the fallopian tubes have become blocked.

The stage is classified during the same surgical procedure used to confirm a diagnosis, which is called a laparoscopy. During the procedure, a surgeon makes small incisions in the abdomen and inserts a tiny camera to observe the reproductive organs, intestines, and other surfaces.

Stage 1: Minimal Endometriosis

Stage 1 is the earliest stage, in which small, superficial lesions are found in the peritoneum (lining of the pelvic cavity or abdomen). At this point, the disease is minimal, and adhesions are usually absent. By the ASRM classification, this stage includes scores from 1 point to 5 points.

For some, stage 1 comes with few or no symptoms, but that is not always the case. Some might experience light pelvic pain or discomfort during menstruation, and it may be mistaken for normal period cramps.

It is still possible to become pregnant at this stage, because the fallopian tubes and ovaries are generally unaffected. Early diagnosis and treatment can help slow the progression of the disease.

Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Motrin) can help manage pain in stage 1. Hormone therapy, such as birth control or progestin, can also help regulate the menstrual cycle and prevent the growth of more endometrial tissue.

Stage 2: Mild Endometriosis

In stage 2 of endometriosis, lesions become more numerous, but they may be relatively shallow. Filmy adhesions may start to form. This stage includes scores from 6 points to 15 points in the ASRM system. Fifteen or fewer points means the disease is minimal or mild.

With stage 2 endometriosis, you may notice more pronounced pain, especially during your period. Some also report discomfort during bowel movements or intercourse, as the endometrial cells spread to more areas of the pelvic cavity.

At this stage, fertility may start to be impacted, particularly if the fallopian tubes are affected by adhesions. How serious is stage 2 endometriosis? Although it can cause discomfort, it’s often manageable with treatment, and many at this stage can still conceive naturally.

Hormone therapy or birth control can help control the spread of the disease. Regular monitoring with transvaginal ultrasounds or magnetic resonance imaging (MRI) can help you and your doctor track the progression of the disease. If fertility is a concern, your doctor may suggest early reproductive medicine interventions at this stage.

Stage 3: Moderate Endometriosis

At stage 3, lesions are deeper and more widespread, and adhesions may begin to involve the fallopian tubes and other reproductive organs. Ovarian cysts, often called chocolate cysts or ovarian endometriomas, are more common. This stage includes scores from 16 points to 40 points. Scores of 16 points or more are considered moderate to severe endometriosis.

The pain in stage 3 can be significant and interfere with daily activities. Pelvic pain outside of menstruation is common, as are severe menstrual cramps and pain during intercourse. Bowel and bladder symptoms may also develop.

Fertility is more likely to be impacted in stage 3 endometriosis, because adhesions can obstruct the fallopian tubes or damage the ovaries. At this stage, many people require fertility treatments like in vitro fertilization (IVF) to help conceive, but only your doctor can determine the chance of IVF working for you. Surgery to remove scar tissue may also improve fertility rates at this stage.

Your health care team may recommend laparoscopic surgery to remove endometrial implants and adhesions. This can improve fertility outcomes and reduce pain. Hormone therapy is often used to prevent the recurrence of endometriosis tissue, while laparoscopy remains the most reliable way to assess and treat moderate endometriosis.

Stage 4: Severe Endometriosis

Stage 4 is the most advanced stage, characterized by large endometrial lesions and many adhesions. At this stage, the disease may reach organs like the rectum or bladder, and you may develop multiple ovarian cysts.

Pain at this stage can be intense and persistent. Severe pain during menstruation, sex, and even urination or bowel movements is common. The spread of endometrial tissue outside the pelvic cavity can severely impact daily life.

Fertility is often significantly affected at stage 4 due to the extensive scar tissue and adhesions. At this stage, many who are trying to get pregnant require surgical intervention and reproductive assistance, such as IVF.

At stage 4, laparoscopic surgery is often necessary to remove endometrial lesions and adhesions. This helps your organs function normally. In some extreme cases, your doctor may recommend a hysterectomy (surgical removal of the uterus). Hormone therapy is also used to help prevent the disease from coming back. Regular monitoring is critical to managing the symptoms and improving quality of life.

Deep-Infiltrating Endometriosis (Unofficial Stage)

Some organizations refer to deep-infiltrating endometriosis (DIE) as stage 5 endometriosis. At this stage, lesions penetrate deep into the tissues, including the bladder, intestines, and possibly the diaphragm. Despite fewer visible lesions, DIE can cause severe symptoms.

People with deep-infiltrating endometriosis sometimes experience debilitating pain that gets in the way of basic life activities, like attending class or working. Other symptoms may include bowel and bladder issues, as well as intense discomfort during menstruation and intercourse.

DIE can severely affect fertility due to the depth of the endometrial implants. Surgery is typically necessary, as are hormone-based therapies. Noninvasive diagnostic tools like MRIs help monitor the disease so that further surgeries aren’t necessary.

Nonsurgical Diagnostic Methods for Endometriosis

In the past, doctors used laparoscopy to diagnose endometriosis. This surgery enabled them to look inside the body for endometrial lesions. Now, thanks to new nonsurgical methods, it’s possible to detect endometriosis earlier and without surgery.

MRIs and transvaginal ultrasounds are two imaging tests that can detect lesions, especially in cases of deep-infiltrating endometriosis. DIE can cause serious symptoms, such as constant pelvic pain, even if there are fewer visible lesions. This is because the lesions in DIE grow deeper into tissues, affecting organs like the bladder or intestines, leading to more severe symptoms than what doctors can easily see.

There’s also new research into biomarkers, which could help detect endometriosis through blood or tissue samples, making it even easier to find the disease early.

These newer methods can help you learn what stage of endometriosis you have without needing surgery, which could lead to faster treatment before the disease gets worse.

How Fast Does Endometriosis Grow?

The growth of endometriosis can vary from person to person. In some cases, it progresses quickly, while in others, it may remain stable for years. Regular checkups using noninvasive diagnostic methods like ultrasounds and MRIs can help track the progression and guide treatment plans.

Talk With Others Who Understand

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