There are more than a dozen different birth control methods, but they basically break down into five groups: hormonal methods, barriers, spermicides, or surgical procedures. Hormonal methods include pills, injections, implants and devices filled with hormones. Barriers include condoms (which also protect against sexually transmitted infections), sponges, and diaphragms. Barriers may include spermicides which are available in gel or foams. Surgical procedures include tubal ligation, vasectomies, and hysterectomies.
Each method has advantages and disadvantages. Oral contraceptives are convenient but must be taken every day and may have side effects. Condoms and diaphragms avoid any risk of medication side effects but must be applied or inserted prior to intercourse, which some people dislike. Intrauterine devices (IUDs) must be inserted into the cervix, and can increase bleeding and cramping during periods. Each woman or couple must make a decision based on their own circumstances.
Other than abstinence, no form of birth control is 100% effective. Using the method exactly as it is intended each time increases the odds that you will prevent pregnancy. Combining methods (such as using both a condom and a spermicide) decreases the risk of pregnancy. Hormonal implants, IUDs and female sterilization are most likely to prevent pregnancy. Spermicides used alone have a higher pregnancy rate than other methods.
Many birth control methods have minor side effects. For example, spermicides can cause vaginal itching. An IUD can migrate from the cervix and penetrate the uterus. Oral contraceptives may increase the risk of blood clots, make migraines worse or increase the risk of certain cancers. Risks depend on things like age, family medical history, chronic diseases in the patient and lifestyle factors like smoking.