Ovarian Cysts

Ovarian cysts are fluid-filled sacs or pockets within or on the surface of one of the ovaries. Many women will develop them at some time during their lives and they are usually discovered during routine pelvic examinations. Most ovarian cysts are painless and cause no symptoms, usually disappearing on their own without the need for medical attention.

There are two main types of ovarian cyst: functional and pathological.

Functional Cysts functional ovarian cyst

Most ovarian cysts develop as a result of the normal function of the menstrual cycle. These are known as functional cysts and are the most common type. Functional cysts are usually harmless, rarely cause pain and often disappear on their own within two or three menstrual cycles.

 There are two types of functional cysts; follicle and corpus luteum. 

Follicle Cysts

During the menstrual cycle, an egg grows inside a sac located inside the ovaries, which is called a follicle. Generally, this follicle will break open to release an egg, but if this does not happen, the fluid found inside the follicle may produce a cyst on the ovary.

Corpus Luteum Cysts

Normally, follicle sacs will dissolve after to release of an egg. However, if the sac does not dissolve and the follicle seals, then extra fluid may develop inside of the sac, causing a corpus luteum cyst.

Pathological Ovarian Cysts

These type of cysts are far more uncommon and have formed as a result of an abnormal cell growth, rather than the normal function of your menstrual cycle.

These cysts include; dermoid cysts, cystadenomas and endometriomas.

Dermoid Cysts

These are cysts which contain tissue, such as hair, skin, fatty tissue or teeth and can grow quite large. This type of cyst develops from cells which make eggs in the ovary and has the possibility to develop into any type of cell. They should be surgically removed.


These cysts develop from cells which cover the outer layer of the ovary and may be filled with a watery liquid or a mucous material. Instead of growing inside the ovary, cystadenomas are typically attached by a stalk to the ovary, and as such, they can grow to a very large size. Most are benign and, therefore not cancerous, though they should still be surgically removed.

Both dermoid cysts and cystadenomas can grow exceptionally large and cause ovarian torsion, which is a very painful twisting of the ovary caused by the growth blocking the blood supply.


These cysts develop as a result of endometriosis, a condition in which uterine endometrial tissue grows outside the womb, causing cysts on the ovaries. Endometriomas may also be referred to as chocolate cysts, since the blood found within the cysts look like chocolate.

Ovarian cyst symptoms

Ovarian cysts usually occur naturally and do not cause problems, unless they split or rupture, are particularly large in size or are blocking the blood supply to the ovaries.

woman with abdominal pain

In any of the above cases, symptoms may include:


Since most ovarian cysts show no symptoms or signs, they often go undiagnosed. Most are found during unrelated routine pelvic examinations or ultrasounds. However, if a woman is experiencing any symptoms of ovarian cysts, an examination and diagnosis can be made in several ways.

Pelvic ultrasound

An ultrasound scan can be carried out to confirm the presence of a cyst, help identify its location and determine the consistency (if it is sold or filled with fluid). This involves placing a probe inside the vagina and a wand-like scanner (transducer) over the abdomen, where the ovaries are. Like a pregnancy ultrasound, the doctor observes the internal organs on a screen.

If a cyst is found during the ultrasound, this may be monitored and a repeat ultrasound carried out a few weeks later, or your GP may immediately refer you to a specialist gynaecologist if necessary.

CT or MRI scans

An MRI or CT scan may sometimes be necessary if an ultrasound is inconclusive regarding the location or nature of the cyst. MRI scans use magnetic waves to produce detailed images of internal organs. CT scans use body imaging devices to create cross-sectional images of the internal organs. Both can provide more in-depth analysis and diagnosis of medical issues.

CA125 blood test

Where there is a tumour present, the blood levels of the CA125 protein are often elevated, which could signal ovarian cancer. As such, this blood test is used to help determine whether an ovarian cyst could be cancerous. However, elevated CA125 levels can also occur in non-cancerous conditions, such as endometriosis, uterine fibroids and pelvic inflammatory disease.


Treatment of an ovarian cyst depends upon its cause, size and appearance, whether the patient is experiencing symptoms and whether she has been through menopause.

Doctor talking to patient

Possible treatments include:

Watchful waiting 

Where a cyst is small and does not cause any problems or discomfort, your GP may suggest taking a ‘watchful waiting’ approach, which involves monitoring the cyst, but withholding treatment. In such cases, an ultrasound scan may be recommended every three months to determine any changes to the cyst.

In many cases, the ovarian cysts will remain the same size decrease, or even disappear, in which instance no action is usually required.

Most functional cysts tend to disappear on their own without causing any problems to the woman, so this option prevents a woman undergoing treatment where it is not necessary.

Contraceptive pills 

These are used to stop ovulation and can, therefore, help prevent some types of new cysts from developing. They can also help reduce the risk of developing ovarian cancer.


Where a cyst is large, persistent, causing uncomfortable or painful problems, or appears cancerous, your GP may recommend undergoing surgery to remove the cyst or in some cases, the whole ovary. There are two types of surgery which are used to remove ovarian cysts; laparoscopy and laparotomy. In the vast majority of cases, the operation is done via laparoscopic keyhole surgery.


Most ovarian cysts can be removed using a keyhole procedure (laparoscopy) in which three or four small (5-10mm) incisions are made on the tummy wall. Gas is then blown into the pelvis in order to give the surgeon access to the ovaries. A camera and special surgical instruments (laparoscope) are then inserted to remove the cyst, whilst healthy ovarian tissue is preserved. The cyst is then put in a plastic bag, decompressed and removed, with no spillage inside the tummy. Once the cyst has been removed, the incisions will be closed up using dissolvable stitches.

Minimally invasive keyhole surgery avoids the need for a large incision and has the advantage of reduced hospital stays, quicker recovery times and an easy return to normal life.


Where a cyst is exceptionally large or there is a high chance that it could be cancerous, a laparotomy might be the best medical option.

During a laparotomy, a single, large incision is made in the abdomen to allow the surgeon to have easy access to the cyst. From here, the entire cyst or, in some case, the ovary, is removed and sent off to a laboratory for testing for cancer. Once complete, stitches or staples are used to close the cut.

This is the less preferred option since it is more invasive and usually requires a hospital stay following the procedure.

Read more about Treatment for Ovarian Cysts here


Do ovarian cysts always need removal?

Not all ovarian cysts need removal. Functional (follicular) cysts will often resolve spontaneously on their own accord. Surgery may be needed if the cysts are persistent or if there are symptoms (see above). If there is a suspicion of cancer, urgent surgery is necessary to make a diagnosis and also to provide treatment.

Will I lose my ovary?

Whether the surgery involves removing only the cyst or the entire ovary depends upon your age and what is found during the procedure. If malignancy is suspected, then the ovary should be removed in order to avoid rupture and spillage of the cyst content. In every other case though, only the cyst will be removed.

How can I prevent recurrent ovarian cysts?

It may not always be possible to prevent ovarian cysts, but going on the contraceptive pill may prevent cyst-formation to a certain degree.

What are the follow-up procedures after removal?

After an ovarian cyst is removed, you will not need further tests if you do not develop any symptoms. However, some types of ovarian cysts, such as endometriomas (chocolate cysts) and functional ovarian cysts, are more likely to recur than others. If you are concerned about recurrent cysts you should undergo yearly pelvic ultrasound scans.

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