A complicated, or complex, ovarian cyst consists of a sac on or inside of the ovary that contains both fluid and solid components, according to EmpowHER. The solid contents distinguish complex ovarian cysts from simple ovarian cysts, which are only filled with fluid.
Three examples of complex ovarian cysts are dermoid cysts, cystadenomas and endometriomas, notes EmpowHER. The solid components of dermoid ovarian cysts can include pieces of skin tissue, hair, teeth or bones. Although dermoid cysts are rarely cancerous, they can grow to a rather large size and cause pain by pushing the ovary out of its normal position.
A cystadenoma cyst is filled with mucous or a watery fluid, explains EmpowHER. Women with this type of complex ovarian cyst do not usually experience symptoms, but the cyst can burst, resulting in severe pain and necessitating emergency surgery.
Endometriomas form when the lining of the womb grows in parts of a woman's body outside of her womb, notes EmpowHER. When patches of lining grow on the ovaries, they bleed during menstrual periods and fill with old, thickened blood since there is nowhere for the blood to exit the body. These cysts produce symptoms such as headaches and stomach pain.