When should I test for STIs?

Many people with STIs have no symptoms. If you think you may have an STI, then we recommend that you get tested.
Most STIs don't show in a test straight away. So you need to wait a few weeks before a test will be accurate. This time is called the window period. The window periods are different for different infections.

If you're not sure about window periods, you should do a test now, and another test at a later date.

How long does it take for STIs to show in tests?

These are the window periods for the tests we use.

• Chlamydia: 2 weeks

• Gonorrhoea: 2 weeks

• HIV lab test: 7 weeks

• Insti HIV test: 12 weeks

• OraQuick HIV test: 12 weeks

• Hepatitis B: 12 weeks

• Hepatitis C: 12 weeks

• Syphilis: 12 weeks

• Trichomoniasis: 1 week

Hepatitis C can sometimes take up to 9 months to show in a test, so if you're not sure when you might have been exposed, do a test now, and another test in 9 months.
We recommend trichomoniasis testing to anyone who is experiencing symptoms like:

• unusual genital discharge that has a strong, fish-like smell

• itching, pain and irritation around the vagina or head of the penis

If you get a negative test result but you are still experiencing symptoms, visit a sexual health clinic. They will be able to help you find the cause, with further testing, and get you any treatment that's needed.

If you may have been exposed to HIV in the last 72 hours, do not wait to test. Get immediate advice on taking PEP.

Written by

Dr Paula Baraitser, Medical Director, SH:24