dependsGenerally speaking, a pap smear is done on the first prenatal visit, but of course it depends upon the patient. If you've had a pap smear within the last year, or over 30 and have had a pap smear in the last three years and it was negative and you've been with the same partner, you don't need one. And, your practitioner should always tell you when you're going to have a pap, so you have the chance to refuse. The reasons for a pap in pregnancy - 1)for many women it's their first, and they may not of otherwise received on. 2) it is believed that cervical cancer "grows" quicker in pregnancy (as with everything in pregnancy).
As for tests for Gonorrhea and Chlamydia, if you think you're at risk and don't want a spec exam, you can ask to do a urine based test.