Non-gonococcal urethritis (NGU) is an inflammation of the urethra caused by some pathogens including Chlamydia, Mycoplasma Genitalium, and Ureaplasma Urealyticum except Gonorrhoea through sexual contact. The symptoms of NGU include a slight burning and pain during urination.


Chlamydia is the leading reason for infecting NGU (accounting for 50% of NGU cases). Chlamydia is bacteria that can be found in the semen and vaginal fluids, but it can also live in the cells of cervix, the urethra, the rectum and sometimes the throat and eyes. As it can be easily transmitted through sexual contact, any sexually active people, even without multiple sexual partners, can be easily infected and spread the bacteria by the secretion of human fluid.

Mycoplasma Genitalium and Ureaplasma Urealyticum

Mycoplasma Genitalium and Ureaplasma Urealyticum can live in the body without causing symptoms. However, when they multiply quickly, it leads to an inflammation of the urethra. Being ill or stressed could also cause the infection. Up to 10% of cases of NGU are caused by ureaplasma urealyticum, and up to 25% by mycoplasma genitalium. It is generally believed that these organisms may be transmitted sexually.


The incubation period for NGU is normally 7-21 days. The signs and symptoms are shown in various periods, subject to the cause of the infection. Usually, they appear within 2-4 weeks after infection, but sometimes it only takes a day or two. In mild cases, symptoms may not show up for several months.

Symptoms of Men:

  • Pain or a burning sensation when urinate
  • A white or cloudy watery discharge from the tip of the penis
  • Pain in the testicles

Symptoms of Women:

  • Increase in the amount of vaginal discharge, with inflammation and erosion
  • Polymorphonuclear leucocytes contained in the vaginal discharge (over 10 per field of view in microscopes with high magnification)
  • Itchiness in the vulva with abdominal discomfort

Patients with NGU usually present symptoms and complications which are similar to but milder than that of gonorrhoea, such as inflammation of the vas deferens, vesiculitis, epididymo-orchitis, orchitis, and sterility in men; salpingitis, pelvic inflammatory disease, ectopic pregnancy, and sterility in women.

It is rare if the infection is in the rectum, but it may cause discomfort and discharge if the infection occurs. Infection in the eyes can cause pain, swelling, irritation, and discharge (conjunctivitis). Infection in the throat is uncommon and asymptomatic.

How is NGU passed on

It can be transmitted through sexual contact. Unprotected sex including oral sex, vaginal sex, anal sex, and the sharing of improperly processed sex toys (e.g. using a new condom or clean thoroughly) can cause the infection.

NGU tests
  • You will be asked to provide a urine sample. Kindly refrain from urinating 2 hours prior to your visit to our clinic
  • If you have had oral or anal sex, our doctors may use a swab to collect cells from your rectum and throat. These swabs are not done routinely
  • If you have conjunctivitis symptoms – discharge from the eye(s) – swabs will also be used to collect cells from your eye(s)
  • A swab looks a bit like a cotton bud but is smaller and rounded. It is wiped over the parts of the body that could be infected to pick up samples of discharge and cell. This only takes a few seconds and is not painful, though it may be uncomfortable for a moment.

How soon after sex can I have a test?

It is important not to delay going for a check-up if you think you might have an infection. You can have a test for NGU even if there are no symptoms.

Do I need to have a test to check if Non-gonococcal urethritis (NGU) is gone?

You should receive a follow-up test two weeks after you are healed so as to:

  • Make sure the signs and symptoms do not exist
  • Make sure you complete the treatment according to the instructions
  • Make sure you are not infected
  • Allow our doctors to consult you after a retest
  • Allow our doctors to give professional opinion on how to protect yourself from getting infected

If the signs exist, you may need a re-test and another course of antibiotics.



Hopkins MJ et al. Validation of a laboratory-developed real-time PCR protocol for detection of Chlamydia trachomatis and Neisseria gonorrhoeae in urine. Sex Transm Infect. 2010 Jun;86(3):207-11

Mahony JB et al. Detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Ureaplasma urealyticum, and Mycoplasma genitalium in First-void Urine Specimens by Multiplex Polymerase Chain Reaction. Mol Diagn. 1997 Sep;2(3):161-168

Samra Z et al. Direct simultaneous detection of 6 sexually transmitted pathogens from clinical specimens by multiplex polymerase chain reaction and auto-capillary electrophoresis. Diagn Microbiol Infect Dis. 2011 May;70(1):17-21


The common treatment for NGU is a course of antibiotics.

  • If there is a high chance you have the infection, treatment may be started before receiving the check-up results
  • You will be given treatment if your partner is found to be infected even you do not have any symptoms
  • There are several different antibiotics that can be used, either as a single dose or a longer course (up to two weeks)
  • Some patients may become persistent (keep coming back). If this happens, you may be given a second course or a combination of antibiotics
  • You may also need other treatments if complications occur
  • The antibiotics that are used to treat NGU interact with the combined contraceptive pill, the contraceptive vaginal ring and the contraceptive patch. Tell the doctor if your partner is using these methods so they can advise you on how to ensure you are protected from pregnancy


What happens if NGU is not treated?

If NGU is treated early, it is unlikely to cause any complications. However, without proper treatment, the infection will lead to long-term health problems, including:

  • Infection in the testicles and pain
  • Possibly reduce fertility
  • Inflammation of the joints, which is known as “Reactive Arthritis”. it is sometimes accompanied by inflammation of the urethra and the eye

Pelvic inflammation and long-term pain can occur if NGU is caused by chlamydia. There is still not confirmed if NGU will lead to pelvic inflammation.



“Chlamydia” – The family planning association of UK

“Non-specific urethritis” – The family planning association of UK