The stages of endometriosis

Endometriosis is a medical condition in which the endometrial tissue lining the inside of the uterus starts to spread outside and implants itself on places such as the ovaries, fallopian tube and other organs in the pelvic region. The implants are referred to as endometrial implants.

Endometriosis is measured in different ways, but the most prevalent scale used by doctors is the American Society of Reproductive Medicine (ASRM) scale. According to the ASRM, endometriosis is classified into four stages based on lesions themselves, precisely the number and depth of endometrial implants. However, the ASRM revised their initial classification to incorporate a point system that numerically scales the disease.

The stages of endometriosis as classified by the American Society of Reproductive Medicine are:

Stage 1 (1 to 5 points)

In this stage, the condition is considered minimal. The implants are few in number, small, and shallow. They mainly feature on the tissue linings of the abdomen or pelvis. Generally, the stage is characterised by little or no scar tissue.

Stage 2 (6 to 15 points)

In this stage, the condition is considered mild. Doctors performing a laparoscopy may see more implants, which may be deeper than the ones found in stage 1 endometriosis. Also, there may be some scar tissue.

Stage 3 (16 to 40 points)

The stage is considered moderate. Patients develop not only deep endometrial implants but also have small cysts on at least one ovary, and thick bands of scar tissue called adhesions. The adhesions can make organs to stick together when they should not, and are often the leading causes of the stabbing pains experienced by women who have endometriosis.

Stage 4 (40 or more points)

The ASRM considers this stage severe. Apart from the several deep endometriosis implants, large cysts on one or both ovaries are noticeable during a laparoscopy. Moreover, the stage is characterised by dense adhesions throughout the pelvic region.

It is important to emphasise that the stages don’t correspond to pain and discomfort level. Also, endometriosis doesn’t always transition from one stage to the next. Finally, experts can’t tell with precision why some people have more severe cases of the condition than others.