What are the potential consequences of gonorrhea ("the clap")?

Gonorrhea doesn’t always cause severe symptoms. Sometimes people have quite mild symptoms or none at all, and they may not even notice the infection. If you don’t get treatment, the bacteria could stay in your body. This can result in the bacteria spreading further through your body and leading to complications. It is also possible that you can infect others during sex. The risk of this happening doesn't depend on how severe your symptoms were to start with.

One of the most common complications of gonorrhea is something known as an “ascending infection.” The bacteria spread from the area that was first infected, moving up (ascending) the genital tract. The infection can also spread from the genitals to small glands nearby, causing painful abscesses.

In men, ascending gonorrhea can cause inflammation of the prostate gland (prostatitis). The symptoms may include pain around the perineum (the area between the anus and genitals), fever and problems when peeing or having sex. The seminal vesicles and vas deferens (sperm ducts) can also become inflamed and hurt. If the epididymis is affected, the scrotum may swell up painfully and turn red.

There is not enough research on whether ascending gonorrhea infections reduce men’s fertility.

In women, the bacteria can spread from the cervix (the opening between the vagina and womb) to the lining of the womb, resulting in pain, fever and heavy periods or spotting (bleeding between periods).

If the infection spreads further, the fallopian tubes and ovaries may be affected too. This can cause lower belly pain, stomach ache, fever and constipation. Over time, the infection may lead to scarring and adhesions (where scarring causes tissue to stick together). If that happens, the woman may no longer be able to have children. It can also increase the risk of ectopic pregnancy (where the egg gets stuck in one of the fallopian tubes).

Sometimes, gonorrhea spreads throughout a woman’s pelvic area. The symptoms may be mild but they can also include severe pain, a high fever and chills.

People who have gonorrhea may actually spread the bacteria to other parts of their body themselves. This can happen, for example, if they get discharge on their fingers and it gets into their eyes – or if discharge from their penis or vagina gets into their anus. If their eyes are infected, it can lead to conjunctivitis. The cornea (the clear outer layer at the front of the eye) may also become infected. Left untreated, this can cause blindness.

In rare cases, the bacteria can get into the bloodstream and spread around the body, causing infections elsewhere. This typically results in painful swelling of the joints – the knees, for example. Bones, tendons, the heart and membranes in the brain may become infected too. If that happens, a whole range of symptoms are possible. They include joint pain, headache, nausea, an abnormal heart rhythm (arrhythmia) and dizziness.

Further possible consequences of the infection spreading around the body include bouts of fever, rashes and bleeding in the skin – or even life-threatening blood poisoning (sepsis).

Pregnant women who get gonorrhea have an increased risk of giving birth too soon or having a miscarriage. They also have a higher risk of the infection spreading to their vagina or the lining of their womb after having their baby.

Mothers may pass gonorrhea on to their baby during birth. Then the bacteria usually infect the baby’s eyes, causing their eyelids to stick together. The cornea may become damaged too. If the infection goes untreated, the baby might go blind.

Diagnosing and treating gonorrhea early on can prevent complications and stop the bacteria being passed on to others. For this reason, it’s a good idea to get tested soon if you have symptoms such as pus-like or watery discharge and you think it could be an STI.

People who have a higher risk of catching STIs should also get themselves tested regularly, even if they don't have any symptoms. Testing is the only way to detect symptomless infections and get treatment – and to make sure you don’t pass the bacteria on to others or develop serious complications.