Ovarian Cysts

Ovarian Cysts

What are Ovarian Cysts?

Ovarian Cysts are very common. Women having an ultrasound scan of the pelvis are often found to have small ovarian cysts up to 4-5 cm. These may come and go as part of a normal menstrual cycle, especially just before a menstrual period.

These cysts are usually simple fluid filled sacs within the ovary which generally cause no symptoms, often being diagnosed incidentally on an ultrasound scan. These are known as functional cysts and in most cases, disappear on a follow up ultrasound scan in a few weeks. Women are usually in the younger age group and usually just need reassurance.

Symptoms of Ovarian Cysts:

Most ovarian cysts don’t cause symptoms and disappear over a few menstrual cycles.

Pelvic Pain:

This can range from a dull ache to a sharp pain. Sometimes, ovarian cysts may twist (especially dermoid cysts) or may burst or bleed causing sudden pain. Seek medical advice as you may need hospital admission. Surgery may be needed in some of these situations.

Most ovarian cysts, if needing surgery can be removed using a keyhole laparoscopic (see separate leaflet on Laparoscopy) approach, which allows excellent visualisation and a quick recovery. However, with some very large cysts or if suspected to be cancerous or borderline in nature, an open operation (laparotomy) may be needed.

Sometimes, ovarian cysts can cause dyspareunia (pain during sex), bloating, a swollen tummy, a need to pass urine more often, difficulty with opening bowels, a change in periods or fertility issues. In such situations, seek advice from your doctor who may arrange some tests or refer you to a specialist for appropriate advice.

Ovarian Cyst Accident: 

Sometimes, ovarian cysts can leak or burst and can cause pain. A pelvic ultrasound scan may show very little to be concerned about, except some free fluid in the pelvis, which is the fluid or blood that has leaked out from a simple water filled cyst or a haemorrhagic (blood filled) cyst.

This fluid/blood gets absorbed over time but can cause pain by irritating the nerve supply lining the pelvis and abdomen. Surgery is rarely needed, and, in most women, the pain will settle with painkillers and rest over a few weeks. Young women who have recurrent cysts may benefit from the combined pill (COCP) after discussion.

Corpus Luteal Cyst: 

After ovulation and release of the egg, a corpus luteal cyst may be seen on scan. This disappears on subsequent scans and rarely causes pain or bleeding.

Polycystic ovaries (PCOS): 

Cysts are very small in this situation on scan ranging from 2-9mm and often arranged in a pearl necklace fashion in the ovary. These cysts are empty egg follicles and do not grow to any size or cause pain. PCOS is covered in a separate leaflet.

Pathological Ovarian Cysts:

However, some cysts may be pathological and may need surgery, for example endometriotic cysts (chocolate cysts) or dermoid cysts (teratomas). These are cysts arising from specialised cells normally in the ovary known as totipotential cells which can change into hair, teeth, bone and skin. These dermoid cysts are usually benign.

Rarely, ovarian cysts may be cancerous and cysts that grow rapidly in size or have some worrying features on an ultrasound scan may need further tests, including a pelvic MRI or CT scan and surgery. Cysts in women in the perimenopause or menopause may need closer monitoring or surgery. 

Ca125 blood test:

This is a blood test for an inflammatory marker, that doctors sometimes request to try and identify the nature of an ovarian cyst. Levels of Ca125 can be mild to moderately raised in several conditions, including endometriosis, adenomyosis and during a period.

Very high levels may be sometimes due an underlying cancer, including ovarian cancer. Your doctor will guide you if you need further referral as most women will be able to be reassured by a specialist and with a pelvic scan and repeating the blood test. Routinely testing for Ca125 has not shown any benefit and can raise anxiety levels. 

Dr Nitu Bajekal FRCOG Dip IBLM

Consultant Gynaecologist and Women’s Health Expert

Lifestyle Medicine Physician

Updated January 2020