Ovarian cyst: symptoms, causes and treatment

Most ovarian cysts cause no symptoms at all and are often found by chance on a scan done for another reason. The NHS says an ovarian cyst usually only causes symptoms if it splits (ruptures), is very large, or twists and blocks the blood supply to the ovary. In those cases you may have:

• Pelvic pain, ranging from a dull, heavy sensation to a sudden, severe and sharp pain.

• Pain during sex.

• Difficulty emptying your bowels.

• A frequent need to urinate.

• Heavy periods, irregular periods or lighter periods than normal.

• Bloating and a swollen tummy.

• Feeling very full after eating only a little.

• Difficulty getting pregnant, although the NHS says fertility is usually unaffected by ovarian cysts.

The ovaries are two almond-shaped organs, one on each side of the womb. They release an egg about every 28 days as part of the menstrual cycle and release the sex hormones oestrogen and progesterone. A cyst may affect one ovary or both at the same time.

The NHS describes two main types. Functional cysts develop as part of the menstrual cycle, are usually harmless and short-lived, and are the most common type. Pathological cysts form as a result of abnormal cell growth and are much less common. Cysts can sometimes also be caused by an underlying condition such as endometriosis.

Most ovarian cysts are linked to the menstrual cycle. Each month a follicle (a fluid-filled structure that contains the egg) bursts as the egg is released. The NHS explains that sometimes a follicle does not release an egg, or does not discharge its fluid and shrink afterwards, and then it can swell and become a cyst.

Pathological cysts develop from the cells used to create eggs or from the cells that cover the outer part of the ovary. In some people a cyst is caused by another condition. Endometriosis is one: tissue similar to the lining of the womb grows in other places such as the ovaries, and blood-filled cysts can form in it.

Polyendocrine metabolic ovarian syndrome (PMOS), which was previously called polycystic ovary syndrome (PCOS), is a hormone condition. The NHS says it causes lots of small, harmless cysts to develop on the ovaries, which are small egg follicles that do not grow to ovulation because of altered hormone levels.

The NHS says to see a GP if you have symptoms of an ovarian cyst. It says to ask for an urgent GP appointment or get help from NHS 111 if you have sudden, severe pelvic pain, or pain in your tummy together with feeling sick or being sick.

These can be signs that a cyst has burst or twisted. If you cannot get a GP appointment or the pain is severe and getting worse, call NHS 111 or, if you feel seriously unwell, call 999 or go to A&E.

During recovery from surgery, the NHS says to contact a GP for heavy bleeding, severe pain or swelling in your abdomen, a high temperature, or dark or smelly vaginal discharge, as these may indicate infection.

If a GP thinks you may have an ovarian cyst you will probably be referred for an ultrasound scan, carried out with a probe placed inside the vagina. If a cyst is found you may need it monitored with a repeat scan in a few weeks, or the GP may refer you to a gynaecologist, a doctor who specialises in female reproductive health.

If there is any concern that a cyst could be cancerous, the doctor will also arrange blood tests to look for high levels of chemicals that can indicate ovarian cancer. The NHS stresses that high levels do not necessarily mean cancer, because they can also be caused by non-cancerous conditions including endometriosis, a pelvic infection, fibroids or your period.

Whether a cyst needs treatment depends on its size and appearance, whether you have symptoms and whether you have been through the menopause. In most cases the NHS recommends watchful waiting. This means no immediate treatment, but an ultrasound scan a few weeks or months later to check whether the cyst has gone.

If you have been through the menopause the risk of ovarian cancer is slightly higher, so the NHS says you may be advised to have ultrasound scans and blood tests every 4 months for a year. If the scans show that the cyst has disappeared, further tests and treatment are not usually necessary. Surgery may be recommended if it is still there.

Large or persistent cysts, and cysts that are causing symptoms, usually need to be surgically removed. Surgery is also normally recommended if there are concerns that a cyst could be cancerous or could become cancerous.

There are two types of operation, both usually done under general anaesthetic. A laparoscopy is keyhole surgery through small cuts in the tummy, and the NHS says most cysts can be removed this way. It is preferred because it causes less pain and has a quicker recovery, and most people go home the same day or the next day.

A laparotomy uses a single, larger cut and may be recommended if a cyst is particularly large or there is a chance it could be cancerous. The whole cyst and ovary may be removed and sent to a laboratory. You may need to stay in hospital for a few days.

You will feel pain in your tummy afterwards, which should improve in a few days. The NHS says it may take as long as 12 weeks before you can resume normal activities after either operation. If the cyst is sent for testing, results should come back in a few weeks and your consultant will discuss whether further treatment is needed.

The NHS says ovarian cysts do not usually prevent you getting pregnant, although they can sometimes make it harder to conceive. If you need surgery and have not been through the menopause, the surgeon will try to preserve as much of your reproductive system as possible.

It is often possible to remove just the cyst and leave both ovaries in place, so fertility should be unaffected. If one ovary has to be removed the other will still release hormones and eggs as usual, although it may be slightly harder to get pregnant. Occasionally both ovaries have to be removed, which triggers an early menopause. Talk to your surgeon about fertility before an operation.

Pelvic pain, bloating and period changes also occur in other conditions, which is one reason a scan is needed. The NHS also says the symptoms of ovarian cancer are very common and can be caused by many different conditions, but that it is important to get them checked.

On the NHS the route normally begins with a GP, who may arrange an ultrasound scan and, if needed, a referral to a gynaecologist. For symptoms that could be cancer, the NHS says an urgent referral is usually made within 2 weeks. This does not mean you definitely have cancer.

Private gynaecology services offer scans, consultations and keyhole surgery too, often with quicker access to appointments. The tests, surgical options and recovery are broadly the same. Whichever route you use, ask when the scan results will come back, who will explain them, and what follow-up scan is planned.