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Home / Answered Questions / I had unprotected oral sex and protected vaginal sex with a woman. The unprotected oral sex was long and vigorous and she caused a little bit of trauma on the penis. I did a STD test for Chlamydia and gonorrhea at around two weeks and it came back negative. I did a HIV test at around 35 days after possible exposure as well as a Hep A, B and C and syphilis and herpes which all came back negative. My question is, how high would my risk be and how accurate would my tests results be?

I had unprotected oral sex and protected vaginal sex with a woman. The unprotected oral sex was long and vigorous and she caused a little bit of trauma on the penis. I did a STD test for Chlamydia and gonorrhea at around two weeks and it came back negative. I did a HIV test at around 35 days after possible exposure as well as a Hep A, B and C and syphilis and herpes which all came back negative. My question is, how high would my risk be and how accurate would my tests results be?

Hi

The chance of getting an infection and the time it takes for an infection to show  up on tests is different for each STI.

The Chlamydia and gonorrhea tests done at 2 weeks should be accurate.

HIV tests done in BC are 95% accurate at 6 weeks, but it can take up to 12 weeks. HIV is not commonly passed through oral sex.

For syphilis (passed skin to skin), most results accurate after 6 weeks, but can be as long as 3 months.

For Hepatitis:

• Most Hepatitis C (passed blood to blood) results are accurate after 10 weeks
• Hepatitis A, not commonly passed this way, is usually accurate after 2 – 7 week
• Hepatitis B is usually accurate after 4 weeks.

You might find these two charts useful:

Know Your Chances
• STIs at a Glance

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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