Ovarian cysts often cause no symptoms and come to light when an ultrasound scan is performed for another reason.
The commonest symptom is lower abdominal pain or discomfort. Sometimes acute pain arises when the cyst causes the ovary to twist on its pedicle thereby cutting off blood supply to the ovary. This is called ovarian torsion and is a medical emergency. Torsion occurs in association with around 15% of cysts larger than 4 cm. If not treated quickly, torsion will lead to irreparable damage to the ovary. Pain associated with a cyst can also be due to bleeding into the cyst cavity or to cyst rupture leading to spillage of its contents into the pelvic cavity.
If a cyst becomes very large it can cause the tummy to become swollen and may place pressure on surrounding structures such as the bladder and bowel.