NEW YORK, Feb 22: In a new survey, most women had inaccurate perceptions about the safety and effectiveness of intrauterine devices (IUDs) in preventing pregnancy, say US researchers, who urge doctors to talk more about the benefits of the devices. In particular, many of the study participants didn’t know that IUDs are more effective contraceptives than the birth control pill and that the devices don’t increase the risk of getting a sexually transmitted disease. (agencies)