You said you were FEMALE and you do not want to become pregnant right now, but understand that no method of birth control is 100% effective. You want to find the best method for yourself understanding that even the most effective methods of contraception used properly may still leave you at some small risk of pregnancy and you can deal with those possible risks.
The next choice to make is if you prefer -- and can and want to use -- a hormonal method or a non-hormonal method.
A hormonal method is one which works by manipulating a woman's natural hormonal cycle or balance in any or all of the following ways: suppressing ovulation, making the uterus less hospitable for an egg to implant, and/or thickening cervical mucus to impair sperm mobility. In order for a pregnancy to occur, a fertile egg needs to be available, cervical mucus needs to be of a certain type and the uterine lining needs to be thick enough for implantation: without those things, pregnancy is not likely to occur. Hormonal methods are used by a woman consistently and on a regular schedule, even at times she is not sexually active. Hormonal methods almost always require a prescription, and overall, hormonal methods are currently the most effective methods for preventing pregnancy.
Some common side effects of hormonal methods can be lighter periods (though technically, women on most hormonal methods have withdrawal bleeds, not actual periods) or absent periods, less cramping, decreased PMS symptoms, skin changes, an increase in the amount of time it takes to become pregnant after discontinuing these methods, a more regular schedule of monthly bleeding, spotting between cycles, nausea, more frequent or more severe headaches, breast tenderness, mood changes or increased depression or anxiety, a decrease in sexual desire, vaginal dryness, weight or body composition changes, and/or more frequent yeast infections. Rare but more serious side effects can include allergic reactions, blood clots, embolism or stroke, heart attack, gallbladder disease, thrombosis or eye problems.
Hormonal methods are often a good choice for women who have certain menstrual problems, like very heavy cramps or bleeding, have endometriosis or ovarian cysts, have PMS, want a form of contraception that they don't have to remember or think about at the time of sex, can get regular sexual healthcare and have easy access to a pharmacy, who can stick to a regular schedule of administering the method even at times of sexual inactivity, those comfortable with "invisible" protection which they can't see working, and those who don't have to worry about missing a dose because of having to hide their use of a method from parents or partners.
Hormonal methods are often not the best choice for smokers, women over 35 (though some hormonal methods can be used by smokers and women over 35), and people with a history of high blood pressure or high cholesterol, blood clots or stroke, liver disease, diabetes, migraine headaches, depression, breast cancer or a family history of breast cancer, or for women who are breastfeeding. However, some hormonal methods -- progestin-only methods -- can be used by women with some of those issues when doctors don't advise other hormonal methods (combination hormone methods). For younger women, some hormonal methods may also potentially interfere with bone growth/strength or proper cellular breast development.
Non-hormonal methods are usually divided into two groups: barrier methods and behavioral methods. Barrier methods work by providing a barrier between sperm and the cervix -- the opening to the uterus. Behavioral methods work by partners adapting their sexual behavior in such a way as to reduce the risks of pregnancy. Overall, non-hormonal methods are slightly less effective than hormonal methods, and of barrier and behavioral methods, barrier methods are usually more effective, especially for younger people. The Copper-T IUD is also non-hormonal, but is neither a barrier more behavioral method and has a higher level of effectiveness than other non-hormonal methods.
Most non-hormonal methods do not have side effects, since they do not change the body or its function in any way. They do not chemically interfere with sexual drive, a person's mood or overall health, the menstrual cycle (the exception there is the Copper-T IUD), fertility or weight. Some barrier methods, for some women, may increase the chances of urinary tract infections or vaginal flora imbalances, and some people may have sensitivities to some barrier methods or spermicides used with them. Of course, condoms carry the side effect of reducing the risk of STIs, and cervical barriers may also reduce risks of cervical infections.
Non-hormonal methods are often a good choice for women looking to avoid the side effects of hormonal methods or who cannot use hormonal methods, for those who only want to use a method at the time of any sex, who want very quick reversibility in terms of their fertility, who may have issues regularly paying for or administering hormonal methods, who have the ability to use that method at the time of sex consistently (and with some methods, who have partners willing and able to cooperate with use of that method), who like to be able to see their method to know it's working, who have religious or ethical objections to hormonal methods and/or who want their male partners to be more involved with birth control.
Non-hormonal methods are usually not the best choice for women with uncooperative partners (but then, of course, we'd say your best method is probably ditching the dopey partner), who have a hard time remembering to use a method at the time of sex or who do not want even a minute interruption during sex, for those sensitive to any materials or agents used with a given non-hormonal method (though there are usually alternatives: latex-sensitive people, for instance, can use non-latex condoms), for those uncomfortable touching their own genitals and/or talking about birth control at the time of use with a partner (and I think you know what we'd tell you with that one, too).
Non-hormonal methods include: condoms (male or female), diaphragms, cervical caps, the Lea's Shield, the sponge, spermicides, the Copper-T IUD, the fertility awareness method or withdrawal. As well, choosing not to engage in sexual activities which pose any risk of pregnancy is also a behavioral method.
Got it? Okay. Choose one of the following:
Take me to the next page to find a HORMONAL METHOD.
Take me to the next page to find a NON-HORMONAL METHOD.