In 1965, the U.S. Supreme Court decision Griswold v. Connecticut legalized birth control in all states, but contraception itself is at least as old as Aristotle. The fourth-century Greek philosopher proposed using natural chemicals such as cedar oil, lead ointment and frankincense oil as spermicides.
Birth control methods or forms of contraception include hormones; mechanical barriers; ways of timing intercourse to avoid pregnancy; and permanent, surgical procedures to end fertility.
Oral Contraceptives
Birth control pills are also called oral contraceptives. There are two basic types: those containing only progestin, sometimes called "minipills," and the more common form containing both estrogen and progesterone. The three groups of women for whom the progesterone-only pills may be advantageous are breast-feeding mothers, women over 35 who smoke and women who can not safely take estrogen because of a risk of estrogen-dependent cancers.
Combination oral contraceptives come in four types, depending on how they balance estrogen and progestin throughout the cycle. Monophasic pills deliver the same dose of estrogen and progestin for 21 days or, in the case of the pills designed to give a woman just four menstrual periods a year, for 91 days. The U.S. Food and Drug Administration reports that monophasics are least likely to cause side effects, such as mood changes, that can result from fluctuating hormone levels in the body.
Biphasic and triphasic oral contraceptives vary the amount of progestin either once or twice during a 21-day cycle. They were designed to reduce some of the common side effects of monophasic contraceptives, such as bleeding between periods and skipping menstrual periods.
Hormonal Injections and Devices
Hormones can also be delivered by injection or by insertion of a device saturated with the hormones.
Depo-Provera is an injectable contraceptive that contains only progesterone. It requires an injection every three months. Due to concerns that it causes a decrease in calcium absorption, which could lead to osteoporosis, Depo-Provera is indicated only when other hormonal contraceptives are not possible. This includes treating women who can't remember to take birth control pills daily, as well as older smokers and breast-feeding mothers who cannot tolerate progestin-only oral contraceptives but cannot take estrogen safely.
Another form of progestin-only contraception is a surgically inserted, matchstick-sized implant called Implanon. Unlike the older version, Norplant, which had five small sticks, Implanon is a single rod that is implanted under the skin of the upper arm. This decreases the chance of it migrating, as Norplant sometimes did, and it is easier to insert and remove. Implanon is effective for three years.
Women who do not want to take their combination pill each day can choose a small vaginal ring, called NuvaRing. It contains both estrogen and progestin and is inserted for three weeks each month.
Barrier Contraceptives
Barrier methods of contraception include condoms, diaphragms, cervical caps and the contraceptive sponge.
Of all methods of contraception, only latex condoms protect against the transmission of sexually transmitted infections and HIV.
Diaphragms and cervical caps require the additional use of a spermicidal gel to be effective, whereas the contraceptive sponge contains the spermicide and is available without a prescription.
Natural Family Planning
For women who want to control their fertility by timing intercourse to either conceive or avoid pregnancy, several methods of fertility recognition are at their disposal. Sympto-thermal fertility awareness is performed by taking the body temperature each morning and combining this information with a self-assessment of the cervical mucous texture.
In the August 2005 issue of "Contraception," David Grimes, M.D., reviewed two controlled trials in Los Angeles, in an effort to determine the effectiveness of fertility awareness methods. He found that many people in these studies discontinued using the method and, because of this, it was not possible to accurately assess the pregnancy rate among those studied.
Permanenent Contraception
When a man decides he is no longer open to fathering a child, a surgical procedure called a vasectomy can render him permanently sterile. This procedure takes place at a doctor's office.
For women, two options exist. The older of the two is bilateral tubal ligation, or BTL, which is the surgical severing of the fallopian tubes. Seven-hundred thousand women in the United States choose this procedure every year, most commonly right after the birth of their final child.
In November 2002, the U.S. Food and Drug Administration approved a method of permanently closing the fallopian tubes through the uterus called Essure. The procedure involves a doctor inserting a small coil in each tube. Unlike BTL, Essure is not considered effective for three months.
References
- Public Broadcasting Service: The American Experience-The Pill
- National Institutes of Health, Medline Plus: Oral Contraceptives
- Center for Menstrual Disorders and Reproductive Choice: Oral Contraceptives
- Planned Parenthood: Vaginal Ring
- "Contraception"; Fertility Awareness-Based Methods for Contraception: Systematic Review of Randomized Controlled Trials; David Grimes, M.D.; August 2005
