The cause of Endometriosis remains unknown. However, majority of research done did indicate that Endometriosis is exacerbated by estrogen. At the moment there are no treatments, which can fully cure endometriosis.

Several theories have become more accepted, and reality is that it may be a combination of factors, which make some women develop Endometriosis.

Some possible theories are indicated in some research such as metaplasia, retrograde menstruation, genetic disposition, Immune system dysfunction and environmental influences such as toxins in the environment.These will affect the reproductive hormones and immune system response, though this theory has not been proven and remains controversial.