Ovarian cysts

Ovarian cysts are fluid-filled sacs that develop in or on your ovaries. They’re quite common and you can get them at any age.

Most ovarian cysts don’t cause any symptoms and they’re usually benign (non-cancerous). Many will go away without treatment. But sometimes an ovarian cyst needs to be removed in a surgical procedure. This may be because the cyst is large, is causing symptoms or there’s a risk it might be cancerous.

Types of ovarian cyst

There are lots of different types of ovarian cyst. These can be split into two groups: functional cysts and pathological cysts.

Functional cysts

Most ovarian cysts are functional cysts. This means that they develop as part of your usual menstrual cycle. They don’t happen after the .

Each month, your ovary produces several follicles (tiny fluid-filled sacs). One of these will mature and release an egg. After releasing the egg, the follicle normally changes into something called the corpus luteum. This releases hormones that help the lining of your uterus (womb) prepare for pregnancy. If the egg isn’t fertilised, the corpus luteum begins to break down.

The two main types of functional cyst form at different stages in this cycle.

• A follicular cyst can happen if a follicle doesn’t release an egg but carries on growing.
• A corpus luteum cyst can form if the corpus luteum doesn’t break down. It may continue to grow and become filled with blood.

Pathological cysts

These may happen because of an overgrowth of cells. You may hear these types of ovarian cyst referred to as tumours. But this doesn’t necessarily mean that they’re cancerous. Most aren’t. To find out more about ovarian cysts and cancer, see our FAQ: Does having an ovarian cyst mean I have cancer?

You can also get cysts on your ovaries if you have endometriosis or polycystic ovary syndrome (PCOS). 

Symptoms of ovarian cysts

Most ovarian cysts don’t cause any symptoms, so you may not realise you have one. But, depending on the type you have, ovarian cyst symptoms may include:

• pain or discomfort in your lower abdomen (tummy)
• pain during sex
• needing to pee more often or urgently
• finding it more difficult to poo
• feeling pressure in your back passage that makes you feel you need to go to the toilet
• feeling bloated
• getting indigestion or heartburn or feeling very full after you eat
• having painful periods or a change in the pattern of your periods

These can be symptoms of other problems as well as ovarian cysts. If you have any of these symptoms or are worried, contact your GP for advice. For information about symptoms that need urgent medical help, see our section on complications.

Diagnosis of ovarian cysts

Most cysts on your ovaries don't cause any symptoms. You may only find out you’ve got one if you’re having tests such as an ultrasound scan.

If you see your Doctor because you’ve got symptoms of an ovarian cyst, they’ll ask you about these. They’ll then examine your abdomen (tummy). Your Doctor may also examine you internally with a vaginal examination.

Your Doctor  may recommend the following tests.

• Transvaginal ultrasound. An ultrasound probe is placed into your vagina to produce a clear picture of your ovaries.
• Transabdominal ultrasound. This is a scan over your lower abdomen to check for any problems around your pelvic area.
• Blood tests to help rule out cancer, including a test for a substance called CA-125. Your level of CA-125 can be high if you have ovarian cancer, but it may also be raised in other conditions.

Depending on the results, your Doctor  may refer you to a gynaecologist. This is a doctor who specialises in women’s reproductive health.

Treatment of ovarian cysts

If you have an ovarian cyst, you may not need any treatment. Whether or not you need treatment will depend on:

• the type of cyst
• how large it is
• if you have symptoms
• if you’ve been through the menopause

Your personal preferences will also be considered.

'Watchful waiting'

If your ovarian cyst is small and isn’t causing any problems, your doctor may suggest keeping a close eye on it for a while with ultrasound scans. This is called ‘watchful waiting’. Most small cysts on your ovaries disappear on their own and don't cause any problems. So, this approach helps you avoid having treatment you don’t need.

Your doctor will discuss with you when you should have a repeat ultrasound scan. This may be:

• after a year if you’re still having periods
• every four to six months for a year if you’ve been through the menopause

You may also be asked to have another blood test for CA-125. If your ovarian cyst doesn’t go away, your gynaecologist may then recommend surgery to remove it.

Pregnancy

Ovarian cysts during pregnancy nearly always go away without treatment. Your doctor will usually only recommend surgery if the cyst is causing symptoms or is very large.

Surgery

If your cyst is large, causing symptoms or doesn’t go away, your doctor will probably suggest you have surgery to remove it. They‘ll also recommend surgery if there’s a risk your cyst may be ovarian cancer.

There are two ways of carrying out  :

• keyhole surgery (laparoscopy)
• open surgery (laparotomy)

You’re most likely to be offered keyhole surgery, which is usually done as a day-case procedure.

Causes of ovarian cysts

Most ovarian cysts form in response to hormonal changes in your body. So, things that affect your hormone levels can sometimes lead to cysts forming. These include:

• using progestogen contraception – this includes the progestogen-only pill, the intrauterine system (the coil – for example, Mirena) and the contraceptive implant
• being pregnant
• taking hormones used to treat
• taking hormone therapy (tamoxifen) – for instance, for breast cancer
• having an underactive thyroid

You can also get ovarian cysts if you have endometriosis or polycystic ovary syndrome (PCOS).

Complications of ovarian cysts

Having an ovarian cyst doesn’t usually cause any serious problems. The two main complications of ovarian cysts are described here.

• Torsion. This is when the cyst causes your ovary to twist, which cuts off the blood supply to your ovary. You will get severe tummy pain, which may come and go. Ovarian cyst torsion is more common with larger cysts (over 4 cm) and if you haven’t been through the menopause yet.
• Rupture. This is when the cyst suddenly bursts, often during exercise or when you’re having sex. Ruptured ovarian cyst symptoms include sudden, severe tummy pain, vaginal bleeding and nausea. You may also be sick, and you may faint.

If you have been diagnosed with an ovarian cyst and get sudden, severe lower tummy pain, go to your nearest A&E department straightaway. You may need to have surgery.