The hazards of contraceptive pills include increased gynecological morbidity, poor contraceptive effect, and stimulation of male genitals. 1. Increase the prevalence of gynecological diseases: contraceptive pills are inserted into the vagina, which may damage the normal flora of the vagina and increase the prevalence of vaginal inflammation. Frequent use of the pills may cause allergic phenomena such as itchy vagina, foul-smelling secretions, burning sensation of the vagina, and rashes on the vulva. 2. Contraceptive effect is not good: contraceptive pills should be used 5 minutes before sex, such as contraceptive pills to fully dissolve before sex, use to ejaculate within half an hour, contraceptive pills are not fully dissolved or use of ejaculation time is too late may lead to contraceptive failure. 3. Stimulation of the male genitals: contraceptive pills may have a relatively strong stimulation of the male genitals, genitals may have a burning sensation after sexual intercourse, rashes and other symptoms. The reaction of each person may be different after using the pill, and those who are seriously ill should seek medical treatment.