Yes, STIs can be transmitted even when a condom is used.
Condoms provide great protection against some STIs and good protection against others. STIs like HIV, Gonorrhea and Chlamydia are passed through body fluids or found in certain areas and condoms provide a lot of protection against these. STIs like Syphilis and Herpes are passed through skin-to-skin contact and so if the condom does not cover the area on the genitals where the infection is, an infection could happen.
Because of this, STI testing is important even if you are using condoms. Regular testing is recommended for anyone who is has sex with a new partner or multiple partners or if your partner is having sex with other people.
Our Know your chances charts give an idea of how common it is for different infections to pass when a condom is used or not used. Feel free to check them out.
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