Birth Control

Barrier methods are birth control methods that work by creating a physical barrier to try and prevent the passing of bodily fluids from one person to another.

Examples of barrier methods include condoms, female condoms, cervical caps, diaphragms, sponges, and dental dams. Of those, only dental dams and condoms are recommended to prevent the transmission of HIV.

Condoms prevent pregnancy by blocking the passage of sperm and are available without a prescription. Because they act as a mechanical barrier, condoms prevent direct vaginal contact with semen, infectious genital secretions, and genital lesions and discharges. Latex condoms are the most effective method for reducing the risk of infection from the viruses that cause AIDS, other HIV-related illnesses, and other sexually transmitted infections (STIs).

Combined oral contraceptives have been on the market for more than 35 years and are the most popular form of reversible birth control in the United States. This form of birth control is called reversible because it suppresses ovulation (the monthly release of an egg from the ovaries) by the combined actions of the hormones, estrogen and progestin.

Vaginal rings work similarly to oral contraceptives to prevent pregnancy. This flexible ring is embedded with estrogen and progesterone is inserted into the vagina and left in place for 3 weeks. The hormones are released and absorbed into the bloodstream. The ring is removed and replaced after the 4th week.

Implantable birth control is made up of a matchstick-sized rod embedded with progestin. This rod is inserted under the skin of the upper arm, where it steadily releases the contraceptive.

Protection lasts up to three years, or until it is removed.

Depo-Provera is a hormonal injection administered by a health professional every three months. It prevents pregnancy in three ways: it inhibits ovulation, changes the cervical mucus to help prevent sperm from reaching the egg, and changes the uterine lining to prevent the fertilized egg from implanting in the uterus. The injection, which contains the hormone progestin, is extremely effective in preventing pregnancy.

An intra-uterine device (IUD) is inserted into the uterus by a health-care professional.

An IUD can remain in place for up to 10 years, depending on the type of IUD. It's not entirely clear how IUDs prevent pregnancy. They seem to prevent sperm and eggs from meeting by either immobilizing the sperm on their way to the Fallopian tubes or changing the uterine lining so the fertilized egg cannot implant in it.

Surgical sterilization is a birth control option intended for people who don't want children in the future. It is considered permanent because outcomes to reverse these procedures are poor and frequently require referrals to fertility specialists to assist with reproduction. Both men and women can be sterilized.

Natural family planning, also known as fertility awareness, entails not having sexual intercourse on the days of a woman's menstrual cycle when she could become pregnant or using a barrier method of birth control on those days.

Methods to approximate when a woman is fertile are usually based on the menstrual cycle, changes in cervical mucus, or changes in body temperature.