Spermicide as a barrier method of birth control

A spermicide is a substance that kills sperm. Spermicides are available as jelly, foam, cream, suppositories, and film. The active ingredient of most spermicides is a chemical called nonoxynol-9.

Most spermicides come with an applicator. The applicator is filled with spermicide and inserted into the vagina right before intercourse.

• When using a jelly, foam, or cream, you can then have sex right away.
• A spermicide film or suppository is inserted deep into the vagina using a finger and is placed close to the cervix. Film or suppositories must be inserted at least 15 minutes before having sex to allow the spermicide to spread in the vagina.

One application of spermicide is necessary for each act of sexual intercourse.

A nonprescription method

Spermicide use does not require a prescription or a visit to a health professional. Spermicide is sold in drugstores, grocery stores, and family planning clinics.

Spermicide and a condom used together provide a reasonable level of birth control without a prescription. Using spermicide alone is not recommended because it offers poor pregnancy prevention and does not protect against sexually transmitted diseases (STDs). In fact, the nonoxynol-9 in most spermicides may increase the risk of getting HIV/AIDS from an infected partner.

Effectiveness in preventing pregnancy

The most effective strength spermicide contains at least 100 mg of nonoxynol-9 per dose. You are more likely to get pregnant if you use a weaker spermicide. There is no difference in effectiveness between various spermicide types, such as gel, film, or suppository.¹

Typical use failure rate includes all possible users, including people who are careless and those who use a method perfectly every time. Perfect use failure rate includes only people who use a method perfectly every time.

• Spermicide used alone has a high failure rate of 29% for typical users. This means that in 1 year, 29 of every 100 women who use spermicide as their only method of birth control get pregnant. The perfect use failure rate is still high at 18%.²
• Spermicide used with another barrier method (condoms, diaphragm, or cervical cap) is more effective at preventing pregnancy than spermicide alone. For example, spermicide with a diaphragm has an average failure rate of 16%. This means that in a year, 16 of every 100 women who use a diaphragm and spermicide together get pregnant. The perfect use failure rate is much lower, at 6%.²

Vaginal douching is not considered a birth control method even if it is done with spermicides. Douching after intercourse does not prevent sperm from reaching the fallopian tubes, where fertilization takes place.

Effectiveness in preventing sexually transmitted diseases (STDs)

Spermicides used alone do not protect against STDs, including infection with the human immunodeficiency virus (HIV). You must use a condom for the best possible STD protection.

Most spermicides contain a chemical called nonoxynol-9 (N9). The U.S. Food and Drug Administration (FDA) warns that N9 in vaginal contraceptives and spermicides may irritate the lining of the vagina or rectum. This may increase the risk of getting HIV/AIDS from an infected partner.

Advantages of spermicides

• They do not affect future fertility for either the woman or the man.
• They are used only at the time of sexual intercourse.
• They are safe to use while breast-feeding (birth control that contains estrogen affects milk supply).
• They are less expensive than hormonal methods of birth control.
• They are safe for women who have other health problems (birth control that contains estrogen makes some health conditions worse).

Disadvantages of spermicides

Failure rates for barrier methods are higher than for most other methods of birth control. Other disadvantages include the following:

• Spermicides cause an extra discharge from the vagina. Women who use spermicides should not douche for at least 8 hours after intercourse so that the spermicide continues to work to prevent pregnancy. (Douching is not recommended for women in general.)
• Some people are allergic to nonoxynol-9, the active ingredient in most spermicides. They can develop itching or sores in the vagina or on the penis, which make it more likely that HIV can be passed from an infected person during sex.
• The nonoxynol-9 in spermicides may also increase the risk of getting HIV/AIDS from an infected partner.
• Some people are embarrassed to use spermicide and a barrier method or worry that it may interrupt foreplay or intercourse. This can create a problem with using it every time they have sex.

Citations

1. Raymond EG, et al. (2004). Contraceptive effectiveness and safety of five nonoxynol-9 spermicides: A randomized trial. Obstetrics and Gynecology, 103(3): 430–439.

2. Trussell J (2004). The essentials of contraception: Efficacy, safety, and personal considerations. In RA Hatcher et al., eds., Contraceptive Technology, 18th ed., pp. 221–252. New York: Ardent Media.