Endometriosis is a condition where the tissue that normally lines the inside of the uterus grows outside, such as on the ovaries, fallopian tubes, or other organs in the pelvis.

This misplaced tissue can cause pain, heavy periods, and infertility.

What Causes Endometriosis?

The exact cause is unknown, but some suggest it may be related to genetics, hormonal imbalances, or immune system dysfunction.

Several ideas may explain how it develops. One theory is that endometriosis may be caused by retrograde menstruation, which happens when menstrual blood flows back through the fallopian tubes and into the pelvic cavity instead of leaving the body through the vagina.

The endometrial tissue shed during menstruation may then attach to the pelvic organs and grow outside the uterus.

Another theory is that endometriosis may be caused by a problem with the immune system, which may allow endometrial tissue to grow outside the uterus without being attacked and destroyed.

Hormones may also play a role in the development of endometriosis. Endometrial tissue is sensitive to estrogen, and the hormonal changes of the menstrual cycle may cause the tissue to grow and bleed, leading to inflammation and pain.