The most common ultrasound subjective impression was mature teratoma (22/46 cysts), followed by simple cysts (12/46 cysts), haemorrhagic cysts
(6/46 cysts), endometriomas (5/46 cysts) and one possible mucinous Borderline tumour.
In benign masses, simple cyst constituted the largest group (40.0%) followed by haemorrhagic cyst
Diagnosis of a papillary serous cystadenofibroma of right paratubal cyst with haemorrhagic cyst
and massive oedema of right ovary was made.
-- When bleeding occurs inside the cyst leading to pain on one side of the body.
 The benign lesions forming pelvic masses and mimicking ovarian tumours are categorised into follicular cyst, corpus luteal cysts, endometriotic cysts and haemorrhagic cysts
False-positives identified for endometriosis by laparoscopy in this study population included fibrosis, inflammatory changes, normal peritoneum for peritoneal biopsy sample and for adnexal mass serous cysts, haemorrhagic cysts
, corpus luteum cysts, normal ovarian stroma, ovarian hyperthecosis, etc.