The location of the implants, the depth to which they penetrate the tissue they rest upon, and their overall size contribute to the unique nature of this disease. Although there are many differing opinions concerning aspects of endometriosis, one thing everyone agrees on is that every case of endometriosis is different from every other case. We may find similar cases, but none that are exactly alike. The magnitude of endometriosis pain depends in part on where it is and how much you have. However, even the tiniest implant can cause incapacitating pain if it irritates a nearby nerve.
Larger implants can become locally invasive as they respond to hormone stimulation.
The tissue surrounding the implant can begin to break down and bleed. But if active endometriosis becomes trapped beneath adhesions, enormous pain and pressure can result. Then degeneration and destruction of the localized blood can create a cystic mass called an endometrioma. They can also grow very large. I have seen endometriomas the size of a softball.