Endometriosis is broken down into four stages that may or may not cause symptoms. Here's how endometriosis may affect you during each of the four stages.

Stage 1: Minimal Endometriosis

The symptoms of stage 1 endometriosis could include:

• Minor pain
• Irritation
• Heavy periods
• Diarrhea
• Constipation
• Fatigue

Stage 2: Mild Endometriosis

Symptoms of stage 2 endometriosis may include:

• More pain, especially during periods
• Heavy periods
• Fatigue
• Diarrhea
• Constipation
• Bloating
• Nausea

Stage 3: Moderate Endometriosis

At this stage, it's possible that you might start to have ovarian cysts (if you haven't already). You may also develop adhesions from scar tissue. Symptoms may include:

• Painful periods
• Pain during sex
• Pain in the lower back and thighs
• Reduced fertility
• Nausea
• Fatigue
• Bowel or bladder symptoms

Stage 4: Severe Endometriosis

Women who have stage 4 endometriosis have the most severe form. This is when the disease has spread the most and may be deeply implanted around the abdomen, pelvis, and possibly in other parts of the body. It's normal to see large ovarian cysts during this stage as well. Some stage 4 symptoms may include:

• Pain when urinating
• Painful bowel movements
• Infertility
• Heavy or abnormal menstrual flow
• Excessive menstrual cramping in the abdomen and lower back or legs

If you have endometriosis, you may be wondering why. This is a complex disease that impacts women all over the world, so there is not one specific demographic that is more at risk. It's not known exactly why everyone who gets endometriosis has developed it. Studies are still ongoing. Some of the reasons that you may develop endometriosis could include:

• Cellular metaplasia, which is when certain cells are able to change from one form to another easily
• Stem cells, which may cause the disease and then spread throughout the body through the lymphatic system or blood
• Retrograde menstruation, which is when menstrual blood goes backwards up into the fallopian tubes and into the pelvic cavity
  

Since endometriosis has such varied symptoms, it's not always easy to diagnose it. You may have pain or heavy periods without endometriosis being a cause, for example. Unfortunately, since it's hard to diagnose, some people wait a long time before they receive a diagnosis.

To get the condition diagnosed, you may need a laparoscopy. This is a surgery during which your doctor will look inside the abdomen and pelvis to visualize lesions and adhesions. Other signs, like developing endometriomas on the ovaries, may be identified with an ultrasound or with magnetic resonance imaging (MRI).

There is no known cure for endometriosis, but you can get help to resolve pain and other symptoms. Depending on the severity of the condition, you may be able to use treatments such as the following to control endometriosis:

• Contraceptive steroids
• Non-steroidal anti-inflammatory medications
• Analgesics
• Birth control
• Progestins
• GnRH-analogues
• Surgery to remove lesions, scar tissue and adhesions
• Physiotherapy

If you're struggling with fertility issues, you may have options such as:

• Intrauterine insemination
• In-vitro fertilization

In some severe cases, there may be other methods of controlling symptoms of endometriosis or eliminating as much of the disease as possible. Hysterectomies or uterine ablations may be used for women with severe pain or dangerously heavy periods, for example.