The only reaction to the success of birth control pills is the normal onset of menstruation and no other corresponding reactions. Some people may experience nausea and vomiting after taking the pill, while others may experience dizziness, mainly because of individual differences in clinical symptoms. In addition, it is difficult to determine whether the contraceptive has succeeded or failed before the menstruation, so do not expect to find the contraceptive successful or failed before the menstruation, only when the menstruation does not come, and after the clinical test is pregnancy indicates that it has failed. If you have a normal period, the contraception is successful.