Endometriomas, also known as chocolate cysts, form when endometrial tissue gets on the ovary. This irritates the ovary, causing the cyst to grow. In a ultrasound it will look like this:
You see how there are two types of materials within the cyst? One side is solid, dried blood. The other is a viscous fluid.
This type of cyst leads most doctors to recommend surgery. It is very hard to tell whether a cyst is endometrial or cancerous when you do the ultrasound. Often endometrial cysts are septated – that is, they have walls. They may appear solid on the ultrasound due to dried blood. There is often several on one ovary.
Plus, endometriosis causes your CA-125 levels to be elevated. This is also a sign of ovarian cancer. The doctor will then want to remove the cyst to rule out that possibility. Of the surgeries performed, only 10% turn out to be cancerous.
Here is a picture of the removed endometriomas:
You can see where it gets the name, “chocolate cyst.” The brown stuff is actually endometrial lining and dried blood, the same that you would shed normally during a period.
Surgery is generally recommended to treat this type of cyst. However, it can recur. It has been shown that increasing your progesterone levels can help thin endometrial tissue. You can do this through progesterone only birth control pills and natural progesterone creams.
You also want to make sure that your liver is properly removing excess estrogen from your body, as estrogen encourages the growth of endometrial tissue. This can be done safely through diet and gentle cleansing.