Ovarian cyst

An ovarian cyst is a fluid-filled sac that develops on a woman’s ovary. They are very common and do not usually cause any symptoms.

In most cases, they are harmless and usually disappear without the need for treatment. However, if the cyst is large or causing symptoms, it may need to be surgically removed (see below).

An ovarian cyst will usually only cause symptoms if it ruptures (splits), is very large, or if it blocks the blood supply to the ovaries. If this is the case, you may have the following symptoms:

pelvic pain
difficulty emptying your bowels
a frequent need to urinate
a change to your periods, heavy, lighter or irregular
indigestion or a feeling of fullness and bloating
tiredness

Read more about the symptoms of ovarian cysts.

The ovaries

The ovaries are two small, bean-shaped organs that are part of the female reproductive system. A woman has two ovaries, one each side of the womb (uterus).

The ovaries have two main functions. They:

release an egg approximately every 28 days as part of the menstrual cycle
release the female sex hormones, oestrogen and progesterone, which play an important role in female reproduction

Types of ovarian cyst

There are a number of different types of ovarian cyst. The two main types are:

functional ovarian cysts - they develop as part of the menstrual cycle and are harmless and short-lived, they are also the most common type
pathological ovarian cysts - they occur as a result of abnormal cell growth (most pathological ovarian cysts are not cancerous) and are much less common

Read more about different types of ovarian cysts.

Diagnosing ovarian cysts

As most ovarian cysts do not cause symptoms, they often go undiagnosed. Or they are diagnosed by chance - for example, during a pelvic examination or ultrasound scan for an unrelated reason.

If you have symptoms that could be caused by an ovarian cyst, you will probably be referred to a gynaecologist (a doctor who specialises in female reproductive health) for a vaginal examination.

Read more about how ovarian cysts are diagnosed.

Treating ovarian cysts

Whether an ovarian cyst needs to be treated will depend on:

its size and appearance
whether you have any symptoms
whether you have had the menopause (post-menopausal women have a slightly higher risk of developing ovarian cancer)

In most cases, the cyst often disappears after a few weeks. A follow-up ultrasound scan may be used to confirm this.

Due to the slightly increased risk of post-menopausal women developing ovarian cancer, regular ultrasound scans and blood tests are usually recommended until the cyst disappears.

Large cysts, or those that cause symptoms, may need to be surgically removed. Your gynaecologist will be able to discuss this with you.

Read more about how ovarian cysts are treated.

Fertility

Ovarian cysts do not usually affect a woman's ability to conceive.

If the cyst is large and needs to be removed, it may be possible to carry out the procedure using keyhole surgery (laparoscopy), which may help preserve your fertility.

However, exactly how this is managed will depend on the specific features of the cysts, the blood results and the clinical findings in each individual case.