The four main stages or types of endometriosis are:

Subtle: Subtle types look like a small sac or cyst, ranging from 1 to 3mm in size.

They are not serious but can look like ovarian cancer.

Typical: These appear as black spots over a white fibrous area and vary in size from 1 to 2cm in diameter.

They are found around the pelvis and/or diaphragm.

Cystic Ovarian: This stage involves cysts bigger than 4 to 5cm, growing as large as 15cm, and covering the ovary.

They may form adhesions with the wall of the pelvis or other organs in the pelvis.

Deep: In this stage, solid tumors of up to 5 or 6cm in diameter are mostly found in the space between the back wall of the uterus and the rectum.