Chlamydia is a sexually transmitted disease (STD) caused by a tiny bacterium, Chlamydia trachomatis.

If you haven't heard of chlamydia, you're in good company - a substantial proportion of the UK population hasn't heard of it either. Most people who are at risk of this infection don’t really know what it is, or understand it, even if they have heard about it.

Some women may have symptoms such as cystitis, change in vaginal discharge or mild lower abdominal pain. These are very 'non-specific’ symptoms and can be caused by other infections and diseases.

If you go to a GP or family planning doctor with these symptoms, make sure you have a chlamydia test taken. You are perfectly entitled to ask for it if the test isn’t offered spontaneously.

Male symptoms

In men, chlamydia is the most common cause of urethral discharge from the penis.

Sometimes chlamydia can cause mild irritation at the end of the penis, which disappears after two or three days. Many men suffering some discomfort will just wait to see if it goes away.

Unfortunately, the discomfort may disappear but the infection can still be present. They can, therefore, transmit it to a sexual partner and also risk the complication of inflamed and swollen testicles.

Chlamydial infection can affect sperm function and fertility in men. Chlamydia has too often been publicised as a problem that only affects women. Nothing could be further from the truth.