Some Disadvantages Must be taken the same time every day Effectiveness may be reduced by some commonly used medications Side effects may occur in some users. Breakthrough bleeding is the most common side effect. For directions on how to take the pill or if you miss a pill, see our General Birth Control Pill Counseling Points .
Privacy is a major advantage.
No one needs to know you are using this method. It is OK to start a new contraceptive if it is less than 13 weeks since last shot. Some women gain weight. To avoid weight gain, watch your calories and get lots of exercise. You have to return every three months for your injection.