Many authorities recommend that sexually active people with more than one partner routinely visit their health-care practitioner or local public health clinic for periodic checkups, even when no symptoms of infection are evident. In view of the number of people, both women and men, who are symptomless carriers of STIs, this seems like good advice. How often to have such examinations is a matter of opinion. Our advice to people who are sexually active with several partners is that they should have check­ups every 3 months and certainly no less often than twice a year.