Endometriosis is a disorder in which tissue similar to the tissue that forms the lining of your uterus grows outside of your uterine cavity. The lining of your uterus is called the endometrium.
Endometriosis occurs when endometrial tissue grows on your ovaries, bowel, and tissues lining your pelvis. It’s unusual for endometrial tissue to spread beyond your pelvic region, but it’s not impossible. Endometrial tissue growing outside of your uterus is known as an endometrial implant.
The hormonal changes of your menstrual cycle affect the misplaced endometrial tissue, causing the area to become inflamed and painful. This means the tissue will grow, thicken, and break down. Over time, the tissue that has broken down has nowhere to go and becomes trapped in your pelvis.
This tissue trapped in your pelvis can cause:
- scar formation
- adhesions, in which tissue binds your pelvic organs together
- severe pain during your periods
- fertility problems