When most people hear that a grown man is ill with mumps, they probably think straight away of the possible impact on his fertility. It's true that idea that mumps causes infertility is a widely held notion, but in fact, medical evidence shows that this happens very rarely indeed. In a relatively small number of cases, a dose of the mumps will stop a man's sperm production for up to a year, but thereafter it will recover. Sperm production may not go back to its previous level, but more often than not, the man will still be able to get his partner pregnant.

What Is Mumps?
Mumps is a viral infection of the salivary glands located near the ears. It's generally considered a childhood illness, so cases of mumps in post-pubescent girls or boys, or indeed in adults, are quite rare. Having said that, recent health scares regarding the vaccination against mumps (the MMR vaccine), have led to increasing numbers of parents refusing to have their kids vaccinated - meaning that mumps may be enjoying a bit a renaissance among teenagers and grown-ups.

Mumps Symptoms
The mumps virus is highly infectious - it can be spread by direct or indirect contact with an infected person. Symptoms usually develop within 15 to 24 days of initial infection and include:
Swelling and pain in the glands in the neck and around the ears
Difficulty and pain when swallowing
Headaches, pains in the joints, nausea and vomiting, a high temperature, pain in the lower tummy area, extreme tiredness and loss of appetite

Mumps Orchitis
In grown men, however, a particularly nasty mumps symptom is swelling and pain in the testes. This is called "mumps orchitis," and is the connection between mumps and reduced fertility in men. If a man's testicles are going to swell up while he has mumps (they don't always) it will probably happen 4 to 8 days after the other above-mentioned symptoms begin to present. It may be that only one testicle is affected. Approximately 20% of adult men who contract mumps will develop mumps orchitis. The swelling usually goes down within a week, but the testicles may feel sore for a while after that.