Hi and welcome,
The history of endometriosis
and the complex cyst both indicate that this may be a chocolate cyst
which occurs in endometriosis due to the disease affecting the ovary. It is not uncommon. The size is important as bigger cysts will not resolve.
Other reasons might be that this is a follicular cyst
or a cancerous cyst
[ rare] as it is complex. I will need to know your age and cyst size to get closer to a diagnosis. However tests like Ca125, serum AFP and HCG
will help rule out a cancer.
So please discuss this with your gynecologist. If the cyst is small then it may be left untouched and simple treatment of enodmetriosis started and response assessed. If it is big, then a laparoscopic removal may be needed.
Hope this satisfies your query.
Thanks for using HCM.
Feel free to ask any more questions that you may have.
Dr Madhuri Bagde
Consultant Obstetrician and Gynecologist