Yes and no. Pap smears do check for changes to the cervix caused by Human Papilloma Virus (HPV) and in certain cases will check directly for HPV. HPV is the most common STI; it causes cervical cancer and genital warts. Also, some STIs will show up on a pap smear if it is a prevalent infection. These include Chlamydia and Trichomoniasis but the pap smear is not designed to test for these specifically and so they can be missed. Routine testing for STIs can be done easily with a simple q-tip swab at the time of a pap smear.  Contact your doctor today to find out more.