Protecting against unintended pregnancy: an overview of standard contraceptives.

I am 20 and have never gone to see a doctor about birth control. My boyfriend and I have been going together for a couple of years and have been using condoms. So far, everything is fine. Are condoms alone safe enough, or is something else safe besides the Pill? I do not want to go on the Pill.

Letter to the Kinsey Institute for Research in Sex, Gender, and Reproduction

This young woman is not alone in her uncertainty about contraceptive options. A report by the National Academy of Sciences' Institute of Medicine titled The Best Intentions: Unintended Pregnancy and the Well-being of Children and Families attributed the high rate of unintended pregnancies in the United States in part to Americans' lack of knowledge about contraception. About six of every 10 pregnancies in the United States are unplanned, according to the report.

Being informed about the pros and cons of various contraceptives is important not only for preventing unintended pregnancies but also for reducing the risk of illness or death from sexually transmitted diseases (STDs), including AIDS.

The U.S. Food and Drug Administration has approved a number of birth control methods, ranging from over-the-counter male and female condoms and vaginal spermicides to doctor-prescribed birth control pills, diaphragms, intrauterine devices (IUDs), injected hormones, and hormonal implants. Other contraceptive options include fertility awareness and voluntary surgical sterilization.

[This list provides definitions of standard contraceptive methods. The FDA has not updated it to include recently introduced contraceptive methods that are discussed in this SIECUS Report.--Editor]

BARRIER METHODS

Male Condom. The male condom is a sheath placed over the erect penis before penetration, preventing pregnancy by blocking the passage of sperm. A condom can be used only once. Some have spermicide added, usually nonoxynol-9 in the United States, to kill sperm. Spermicide has not been scientifically shown to provide additional contraceptive protection over the condom alone. Because they act as a mechanical barrier, condoms prevent direct vaginal contact with semen, infectious genital secretions, and genital lesions and discharges.

Most condoms are made from latex rubber, while a small percentage are made from lamb intestines (sometimes called "lambskin" condoms). Condoms made from polyurethane have been marketed in the United States since 1994. Except for abstinence, 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 STDs.

Some condoms are prelubricated. These lubricants don't provide more birth control or STD protection. Non-oil-based lubricants, such as water or K-Y jelly, can be used with latex or lambskin condoms, but oil-based lubricants, such as petroleum jelly (Vaseline), lotions, or massage or baby oil, should not be used because they can weaken the material.

Female Condom. The Reality Female Condom consists of a lubricated polyurethane sheath shaped similarly to the male condom. The closed end, which has a flexible ring, is inserted into the vagina, while the open end remains outside, partially covering the labia.

The female condom, like the male condom, is available without a prescription and is intended for one-time use. It should not be used together with a male condom because they may not both stay in place.

Diaphragm. Available by prescription only and sized by a health professional to achieve a proper fit, the diaphragm has a dual mechanism to prevent pregnancy A dome-shaped rubber disk with a flexible rim covers the cervix so sperm can't reach the uterus, while a spermicide applied to the diaphragm before insertion kills sperm.

The diaphragm protects for six hours. For intercourse after the six-hour period, or for repeated intercourse within this period, fresh spermicide should be placed in the vagina with the diaphragm still in place. The diaphragm should be left in place for at least six hours after the last intercourse but not for longer than a total of 24 hours because of the risk of toxic shock syndrome (TSS), a rare but potentially fatal infection. Symptoms of TSS include sudden fever, stomach upset, sunburn-like rash, and a drop in blood pressure.

Cervical cap. The cap is a soft rubber cup with a round rim, sized by a health professional to fit snugly around the cervix. It is available by prescription only and, like the diaphragm, is used with spermicide.

It protects for 48 hours and for multiple acts of intercourse within this time. Wearing it for more than 48 hours is not recommended because of the risk, though low, of TSS. Also, with prolonged use of two or more days, the cap may cause an unpleasant vaginal odor or discharge in some women.

Sponge. The vaginal contraceptive sponge has not been available since the sole manufacturer, Whitehall Laboratories, voluntarily stopped selling it in 1995. It remains an approved product and could be marketed again.

The sponge, a donut-shaped polyurethane device containing the spermicide nonoxynol-9, is inserted into the vagina to cover the cervix. A woven polyester loop is designed to ease removal.

The sponge protects for up to 24 hours and for multiple acts of intercourse within this time. It should be left in place for at least six hours after intercourse but should be removed no more than 30 hours after insertion because of the risk, though low, of TSS.

Vaginal spermicides alone. Vaginal spermicides are available in foam, cream, jelly, film, suppository, or tablet forms. All types contain a sperm-killing chemical.

Studies have not produced definitive data on the efficacy of spermicides alone, but according to the authors of Contraceptive Technology, a leading resource for contraceptive information, the failure rate for typical users may be 21 percent per year.

Package instructions must be carefully followed because some spermicide products require the couple to wait 10 minutes or more after inserting the spermicide before having sex. One dose of spermicide is usually effective for one hour. For repeated intercourse, additional spermicide must be applied. And after intercourse, the spermicide has to remain in place for at least six to eight hours to ensure that all sperm are killed. The woman should not douche or rinse the vagina during this time.

HORMONAL METHODS

Combined oral contraceptives. Typically called "the pill," 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 suppresses ovulation (the monthly release of an egg from the ovaries) by the combined actions of the hormones estrogen and progestin.

If a woman remembers to take the pill every day as directed, she has an extremely low chance of becoming pregnant in a year. But the pill's effectiveness may be reduced if the woman is taking some medications, such as certain antibiotics.

Besides preventing pregnancy, the pill offers additional benefits. As stated in the labeling, the pill can make periods more regular. It also has a protective effect against pelvic inflammatory disease, an infection of the fallopian tubes or uterus that is a major cause of infertility in women, and against ovarian and endometrial cancers. The decision whether to take the pill should be made in consultation with a health professional. Birth control pills are safe for most women--safer even than delivering a baby--but they carry some risks.

Current low--dose pills have fewer risks associated with them than earlier versions. But women who smoke--especially those over 35--and women with certain medical conditions, such as a history of blood clots or breast or endometrial cancer, may be advised against taking the pill. The pill may contribute to cardiovascular disease, including high blood pressure, blood clots, and blockage of the arteries.

One of the biggest questions has been whether the pill increases the risk of breast cancer in past and current pill users. An international study published in the September 1996 journal Contraception concluded that women's risk of breast cancer 10 years after going off birth control pills was no higher than that of women who had never used the pill. During pill use and for the first 10 years after stopping the pill, women's risk of breast cancer was only slightly higher in pill users than non-pd! users.

Side effects of the pill, which often subside after a few months' use, include nausea, headache, breast tenderness, weight gain, irregular bleeding, and depression.

Mini-pills. Although taken daily like combined oral contraceptives, mini-pills contain only the hormone progestin and no estrogen. They work by reducing and thickening cervical mucus to prevent sperm from reaching the egg. They also keep the uterine lining from thickening, which prevents a fertilized egg from implanting in the uterus. These pills are slightly less effective than combined oral contraceptives. (See Vicki Long's article for updates on the efficacy of the mini-pill. --Editor)

Mini-pills can decrease menstrual bleeding and cramps, as well as the risk of endometrial and ovarian cancer and pelvic inflammatory disease. Because they contain no estrogen, mini-pills don't present the risk of blood clots associated with estrogen in combined pills. They are a good option for women who can't take estrogen because they are breast-feeding or because estrogen-containing products cause them to have severe headaches or high blood pressure.

Side effects of mini-pills include menstrual cycle changes, weight gain, and breast tenderness.

Injectable progestins. Depo-Provera is injected by a health professional into the buttocks or arm muscle every three months. Depo-Provera 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 progestin injection is extremely effective in preventing pregnancy, in large part because it requires little effort for the woman to comply: She simply has to get an injection by a doctor once every three months.

Intrauterine devices. An IUD is a T-shaped device inserted into the uterus by a health-care professional. Two types of IUDs are available in the United States: the Paragard CopperT 380A and the Progestasert Progesterone T. The Paragard IUD can remain in place for 10 years, while the Progestasert IUD must be replaced every year.

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. IUDs have one of the lowest failure rates of any contraceptive method.

The IUD's image suffered when the Dalkon Shield IUD was taken off the market in 1975. This IUD was associated with a high incidence of pelvic infections and infertility, and some deaths. Today, serious complications from IUDs are rare, although IUD users may be at increased risk of developing pelvic inflammatory disease. Other side effects can include perforation of the uterus, abnormal bleeding, and cramps. Complications occur most often during and immediately after insertion.

TRADITIONAL METHODS

Fertility awareness. Also known as natural family planning or periodic abstinence, 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.

"Natural family planning can work, but it takes an extremely motivated couple to use the method effectively."

Because a sperm may live in the female's reproductive tract for up to seven days and the egg remains fertile for about 24 hours, a woman can get pregnant within a substantial window of time-from seven days before ovulation to three days after. Methods to approximate when a woman is fertile are usually based on the menstrual cycle, changes in cervical mucus, or changes in body temperature.

Withdrawal. In this method, also called coitus interruptus the man withdraws his penis from the vagina before ejaculation. Fertilization is prevented because the sperm don't enter the vagina.

Effectiveness depends on the male's ability to withdraw before ejaculation. Also, withdrawal doesn't provide protection from STDs, including HIV. Infectious diseases can be transmitted by direct contact with surface lesions and by pre-ejaculatory fluid.

Surgical sterilization. Surgical sterilization is a contraceptive option intended for people who don't want children in the future. It is considered permanent because reversal requires major surgery that is often unsuccessful.

Female sterilization. Female sterilization blocks the fallopian tubes so the egg can't travel to the uterus. Sterilization is done by various surgical techniques, usually under general anesthesia.

Complications from these operations are rare and can include infection, hemorrhage, and problems related to the use of general anesthesia.

Male sterilization. This procedure, called a vasectomy, involves sealing, tying, or cutting a man's vas deferens, which otherwise would carry the sperm from the testicle to the penis. Vasectomy involves a quick operation, usually under 30 minutes, with possible minor postsurgical complications, such as bleeding or infection.

This was reprinted from the web site of the US. Food and Drug Administration (FDA). See www.fda.gov