How long should I wait before getting a test?

Answer

It can take some time after you first have an STI before it can be detected by a test. This is sometimes called the “window period”.  

If there is a chance that you’ve been exposed to an STI it can still be worth taking a test during the window period. That way, if you do test positive, you can begin treatment straight away. 

But if you test negative, it’s often a good idea to do another test at the end of the window period. 

The window periods we recommend are: 

• Chlamydia: 2 weeks after last exposure 
• Gonorrhoea: 2 weeks after last exposure 
• HIV: 8 weeks after last exposure (although tests done after 4 weeks are accurate 9 out of 10 times) 
• Syphilis: 3 months after last exposure 
• Hepatitis B: 3 months after last exposure 
• Hepatitis C: 3 months after last exposure 
• Mycoplasma genitalium: 2 weeks after last exposure 
• Trichomonas: 4 weeks after last exposure