Functional ovarian cysts

This page tells you about functional ovarian cysts. There is information about

What functional cysts are
How they are diagnosed
How they are treated

Cysts are fluid filled sacs and there are several different types that can affect the ovary. Most are benign (not cancerous) and often disappear on their own. Functional cysts are the most common type of ovarian cyst and usually develop during your childbearing years. They arise during the normal process of releasing an egg (ovulation) and are benign.

Once a month the ovary makes a number of small sacs (follicles) which hold the eggs. These follicles are full of fluid, so are a bit like small cysts. Once the egg is mature the follicle breaks open to release the egg. The egg then travels down the fallopian tube ready to be fertilised by sperm. The sac dissolves away and your body absorbs the fluid that was in it.

There are two types of functional ovarian cyst

Follicular cyst
Corpus luteum cyst

Follicular cyst

A follicular cyst can develop when the egg sac (follicle) does not release the egg. Or if the follicle continues to fill with fluid. These cysts usually disappear on their own within a few weeks.

Corpus luteum cyst

These are less common than follicular cysts. They develop after the egg has been released. Instead of dissolving away, the tissue that is left behind (the corpus luteum) fills with fluid and reseals itself to form a sac. They usually disappear on their own within a few months, but can occasionally split (rupture) causing sudden pain and bleeding.

Most functional cysts are small and don’t cause any symptoms. So they often go undiagnosed. If you do have symptoms these might include a dull pain or discomfort, and irregular periods. Your doctor might discover a cyst when doing a pelvic examination or a scan for another medical reason. To confirm you have an ovarian cyst you may have

An ultrasound scan - this uses sound waves to build up a picture of your ovaries
A probe inside the vagina to check the ovaries - this is called a vaginal ultrasound
Blood tests to check a protein in the blood called CA125 - raised levels of CA125 can be a sign of ovarian cysts or ovarian cancer.

You probably won’t need any treatment for a functional ovarian cyst. A few months after being diagnosed, you might have another ultrasound scan, to check that the cyst has gone. But if it doesn’t go away, or is getting bigger and causing symptoms, your doctor may suggest that you have it removed.

To remove the cyst, your doctor will suggest you have a laparoscopy. This is the most common way to remove a cyst. First you have a general anaesthetic. Once you are asleep, the surgeon makes a small cut near your navel (umbilicus or tummy button). The doctor then puts a tube inside that is a bit like a telescope. It has an eye piece so the surgeon can see inside the body. The surgeon removes the cyst through the small cut while looking through the eye piece and then stitches up the cut.

You have this operation under a general anaesthetic. So you will not be able to go home immediately. Your doctor and nurses will want to keep an eye on you until they are sure you have fully recovered. But you can usually go home the same day.