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Complications - Mumps

There are several problems that often occur with mumps. These can be worrying, but they're rarely serious and usually improve as the infection passes.

Swollen testicle

Pain and swelling of the testicle (orchitis) affects 1 in 4 males who get mumps after puberty. The swelling is usually sudden and affects only one testicle. The testicle may also feel warm and tender.

Swelling of the testicle normally begins 4 to 8 days after the swelling of the parotid gland. Occasionally, swelling can occur up to 6 weeks after the swelling of the glands.

Any testicle pain can be eased using painkillers such as paracetamol or ibuprofen. If the pain is particularly severe, contact your GP, who may prescribe you a stronger painkiller.

Applying cold or warm compresses to your testicle and wearing supportive underwear may also reduce any pain.

Just under half of those who get mumps-related orchitis notice some shrinkage of their testicles. In a small number of cases, this can cause infertility.

Swollen ovaries

One in 20 females who get mumps after puberty experience swelling of the ovaries (oophoritis).

This can cause:

The symptoms of oophoritis usually pass once the body has fought off the underlying mumps infection. This does not cause infertility in women.


About 1 in 20 cases of mumps lead to short-term inflammation of the pancreas (acute pancreatitis). The most common symptom is sudden pain in the centre of your belly.

Other symptoms of acute pancreatitis can include:

  • feeling or being sick
  • diarrhoea
  • loss of appetite
  • high temperature
  • tenderness of the belly
  • less commonly, yellowing of the skin and the whites of the eyes (jaundice)

Pancreatitis associated with mumps is usually mild. But you may be admitted to hospital so your body functions can be supported until your pancreas recovers.

Viral meningitis and mumps

Viral meningitis can occur if the mumps virus spreads into the outer protective layer of the brain (the meninges). It occurs in about 1 in 7 cases of mumps.

The risk of serious complications from mumps meningitis is low.

Mild sensitivity to light, neck stiffness and headaches are common symptoms of viral meningitis. These usually pass within 14 days.

If the symptoms are severe seek urgent medical attention.

Rare complications of mumps

Rare but potentially serious complications of mumps include an infection of the brain itself. This is known as encephalitis. This is thought to occur in around 1 in 1,000 people who develop viral meningitis from mumps. Encephalitis is a potentially fatal condition. It requires admission to a hospital intensive care unit.

About 1 in 20 people with mumps experience some temporary hearing loss. Permanent loss of hearing is rare. It's estimated this occurs in around 1 in 20,000 cases of mumps.

Pregnancy and mumps

In the past it was thought developing mumps during pregnancy increased the risk of miscarriage. But there's little evidence to support this.

Pregnant women should avoid close contact with people known to have an active mumps infection.

Pregnant women should not receive the mumps (MMR) vaccine.

Women who are not pregnant and receive MMR vaccine should avoid pregnancy for one month after vaccination.

If you're pregnant and concerned about mumps you should discuss it with your healthcare professional.

Read more about the MMR vaccine

Content supplied by the NHS and adapted for Ireland by the HSE

Page last reviewed: 22 April 2020
Next review due: 22 April 2023

This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 123.