Hi
It’s hard to know someone’s exact risk to getting an STI passed to them as there are usually many different factors, with the main one being does the person have an STI in the first place. As most STI do not show symptoms it is common for the person not to know if they have one. Even if the person did have an STI it is never 100% that it would pass the first time someone had sex.
Have a look at our “Know your chances” oral sex web page, it provides information on what STI can pass with oral sex.
As most STI do not show symptoms I would recommend going for a test if concerned. Have a look at our “STIs at a glance” chart, it provides information on how long you need to wait before getting tested (window period).
Please leave a comment to let us know if this answers your question or if you need more information.
Health Nurse
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