Intrauterine Contraception
An IUD is a small, flexible, T-shaped device inserted by a trained healthcare provider through the vagina and cervix into the uterus to prevent pregnancy. There are two types of IUDs: the Levonorgestrel IUD system and the Copper T.
- Levonorgestrel-releasing IUDs (LNG IUDs) – These devices release a small amount of hormone (levonorgestrel) each day and prevent pregnancy by causing cervical mucus thickening and thinning of the uterine lining (endometrium). As a result, these IUDs may decrease the amount of menstrual bleeding and pain associated with periods. Some people even stop having periods entirely which is reversed when the IUD is removed. LNG IUDs can be left in place for 3-8 years, depending on the type, but they can be removed at any time. LNG IUDs are highly effective at preventing pregnancy.
- Copper T – These devices do not contain hormones. Copper IUDs prevent pregnancy by stopping sperm from making it through the vagina and uterus to reach an egg. Some people may experience heavier or longer bleeding during their period when using a copper IUD. They can be left in place for 10 years but can be removed at any time.
Implant
The implant, Nexplanon, is a small, thin, hormone-containing rod (about the size of a matchstick) that is inserted under the skin in the upper arm by a healthcare provider. It prevents pregnancy by releasing a small, steady amount of the hormone progestin which is absorbed slowly by the body and is effective within 7 days following insertion. The most common side effect of an implant is irregular bleeding. The implant can be left in place for 3 years and fertility returns quickly after the rod is removed.
Injection
The only injectable method of birth control available in the United States is medroxyprogesterone acetate or DMPA (Depo-Provera). This is a long-lasting progestin hormone which prevents pregnancy by stopping ovulation and thickening cervical mucus. Depo-Provera is injected into a muscle, such as the buttock or arm, and is administered by a healthcare provider every 12 weeks (3 months). The most common side effect of Depo-Provera is irregular or prolonged vaginal bleeding and spotting, although people who use it for more than a year may stop having a period while on the medication. A secondary side effect of this contraceptive method is weight gain. Additionally, while ovulation and menstrual periods generally return within 6 months of the last injection, it can take up to 18 months for this to occur. For this reason, Depo-Provera should not be used by people who plan to become pregnant in the next year.
Oral Contraceptives
Combined oral contraceptives, also called “the pill”, contain two hormones: estrogen and progestin. The pill works by preventing ovulation and, when taken properly, is highly effective. There are several types of pills, some that are designed to allow for a monthly period while others allow for a longer time between periods or no periods at all. The most common side effects include nausea, breast tenderness, bloating, and mood changes, which typically improve after 2-3 months. Irregular vaginal spotting or bleeding can also occur and is particularly common during the first few months. Forgetting to take a pill can also cause irregular bleeding.
Progestin-only pills, also called the mini pill, do not contain estrogen, only progestin, which makes it useful for people who cannot or should not take estrogen. The mini pill prevents pregnancy by thickening the cervical mucus and thinning the uterine lining. They are as effective as combination pills if they are taken at the same time every day. The most common side effect of a progestin-only pill is irregular bleeding.
Skin Patches
Birth control patches contain two hormones, estrogen and progestin. They work by releasing hormones slowly through the skin into the bloodstream to prevent ovulation. The patch is worn on the lower abdomen, buttocks, or upper body (excluding the breasts) and is changed weekly, skipping every 4th week for menstruation. The patch may be preferred by some people because it doesn’t have to be taken every day like a pill. Birth control patches are as effective as oral contraceptives in people who are categorized as “normal weight” based on their body mass index, but they are less effective in people who fall into the overweight category. Common side effects are similar to those of a birth control pill (see above) but there may be a slightly higher risk of developing a blood clot.
Vaginal Ring
Hormonal vaginal contraceptive rings are flexible plastic rings which contain estrogen and progestin. The ring is inserted into the vagina where it releases hormones that are slowly absorbed into the bloodstream to prevent ovulation. The ring is worn inside the vagina for 3 weeks and is removed for the 4th week for menstruation. The vaginal rings have similar efficacy and side effects as the combined oral contraceptive pills (see above).
External Condoms
The external condom is a thin, flexible sheath made of latex, plastic, or lambskin that is placed over an erect penis before intercourse. The covering prevents semen, the fluid that contains sperm, from entering the partner’s body. To be effective, it is important to carefully follow instructions when using condoms because they may rip or tear easily. A new condom must be used with each new sexual intercourse encounter. Many people who choose another form of contraception also use condoms as they are one of the best options for protection against STIs and can be used during anal sex to lower the risk of STIs.
Internal Condoms
The internal condom is a pre-lubricated plastic sheath made of polyurethane that is worn inside the vagina to prevent semen from entering. Before intercourse begins, the condom is inserted into the vagina and is removed immediately after. While internal condoms provide some protection against STIs, external condoms provide the best protection. To be effective, internal condoms must be used exactly as directed.
Diaphragm/Cervical Cap
The diaphragm and cervical cap are flexible, reusable, dome- or thimble-shaped cups that are placed inside the vagina covering the cervix. These prevent pregnancy because they block sperm from entering the uterus through the cervix. Diaphragms and cervical caps are available in multiple sizes and require fitting by a healthcare provider. To be effective, they must fit snugly against the cervix, be used with a spermicide, and be left in place for 6-8 hours after intercourse.
Sponge
The vaginal sponge is a small donut-shaped device that contains spermicide which is released after wetting the sponge with water. It is placed in the vagina where it fits over the cervix, acting as a barrier between sperm and the cervix. The sponge works for up to 24 hours and must be left in place for at least 6 hours after the last act of intercourse at which time it must be removed and discarded. The sponge is associated with higher rates of vaginal infections and doesn’t protect against STIs. To be effective, they must be used exactly as directed.
Spermicide
Spermicides are chemical substances used to prevent sperm from reaching an egg. The chemicals damage sperm so they can’t swim. Spermicides come in several forms (foam, gel, cream, film, suppository, sponge, or tablet) and are placed in the vagina before intercourse. They can be used with external condoms and diaphragms/cervical caps. To be effective, spermicides must be used exactly as directed.
These are surgical procedures that permanently prevent people from becoming pregnant or getting a partner pregnant. The two most common forms of permanent birth control are the tubal ligation and vasectomy. These methods should only be considered after all available options have been discussed with a healthcare provider. Learn more about tubal ligation and vasectomy.
Some people cannot or choose not to use the birth control methods mentioned above due to religious, cultural, or personal reasons. Fertility awareness-based methods for preventing pregnancy are based on the physiological changes during the menstrual cycle. These methods, also called natural family planning, involve identifying the fertile days of the menstrual cycle using a combination of cycle length and physical manifestations of ovulation, then avoiding vaginal sex or using barrier methods on those days. Smartphone apps are available that may help with tracking cycles. The effectiveness of fertility awareness methods in preventing pregnancy is lower than for the methods detailed above.
The withdrawal method involves pulling the penis out of the vagina before ejaculation. Withdrawal is approximately 76% effective in preventing pregnancy.
Emergency contraception (EC) refers to the use of medication or IUC after unprotected sex to prevent pregnancy. EC can be used if a condom breaks during sex, when doses of oral contraceptive pills are missed, or after unprotected sex for other reasons (including for victims of sexual assault). The most effective methods of EC are the non-hormonal IUD, Paragard, and the levonorgestrel IUD, Mirena, when inserted within 5 days of the first encounter of unprotected intercourse. These can be used as ongoing methods of birth control.
The emergency contraceptive pill, often referred to as “Plan B” or the "morning after pill", is another method of preventing pregnancy from occurring after an incident of unprotected intercourse or contraceptive failure (i.e., condom breaks, etc.). The emergency contraceptive pill works by delaying ovulation and can be used up to 120 hours (5 days) after unprotected intercourse. ECP is for emergencies only. Using ECP is less effective at preventing pregnancy than using birth control that is used before or during sex (e.g. birth control pills, condom, etc.). ECP is not the abortion pill; if you are already pregnant, ECP will not cause an abortion.
Trained healthcare providers are the best source of information for questions or concerns related to birth control methods. Appointments are available with Student Health Services providers to discuss options and get started with birth control. The Student Health and Well-being Health Promotions Services team also offers consultative sessions regarding birth control methods. Bedsider is an excellent online source for information on choosing a method of contraception. Check the Reproductive Health Access Project for detailed fact sheets on many types of birth control, from external condoms to vaginal rings, available in multiple languages including English, Chinese, and Spanish.
UC San Diego Resources