Spermicide
Encyclopedia
Spermicide is a contraceptive substance that eradicates sperm
Spermatozoon
A spermatozoon is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote...

, inserted vaginally prior to intercourse to prevent pregnancy. As a contraceptive, spermicide may be used alone. However, the pregnancy rate experienced by couples using only spermicide is higher than that of couples using other methods. Usually, spermicides are combined with contraceptive barrier methods such as diaphragm
Diaphragm (contraceptive)
The diaphragm is a cervical barrier type of birth control. It is a soft latex or silicone dome with a spring molded into the rim. The spring creates a seal against the walls of the vagina.-Use:...

s, condom
Condom
A condom is a barrier device most commonly used during sexual intercourse to reduce the probability of pregnancy and spreading sexually transmitted diseases . It is put on a man's erect penis and physically blocks ejaculated semen from entering the body of a sexual partner...

s, cervical cap
Cervical cap
The cervical cap is a form of barrier contraception. A cervical cap fits over the cervix and blocks sperm from entering the uterus through the external orifice of the uterus, called the os.-Terminology:...

s, and sponges
Contraceptive sponge
The contraceptive sponge combines barrier and spermicidal methods to prevent conception. Three brands are marketed: Pharmatex, Protectaid and Today. Pharmatex is marketed in France and the province of Quebec; Protectaid in the rest of Canada and Europe; and Today in the United States.Sponges work...

. Combined methods are believed to result in lower pregnancy rates than either method alone.

Spermicides are unscented, clear, unflavored, non-staining, and lubricative.

Types and effectiveness

The most common active ingredient of spermicides is nonoxynol-9
Nonoxynol-9
Nonoxynol-9, sometimes abbreviated as N-9, is an organic compound that is used as a surfactant. It is a member of the nonoxynol family of nonionic surfactants. N-9 and related compounds are ingredients in various cleaning and cosmetic products. It is widely used in contraceptives for its...

. Spermicides containing nonoxynol-9 are available in many forms, such as jelly (gel), films, and foams, but not recommended by the CDC. Spermicides cause irritation and according to the CDC, studies have shown that spermicides increase the risk of HIV. Contraceptive Technology states that spermicides have a failure rate of 18% per year when used correctly and consistently, and 29% under typical use.

Menfegol is a spermicide manufactured as a foaming tablet. It is available only in Europe.

Octoxynol-9 was previously a common spermicide, but was removed from the U.S. market in 2002 after manufacturers failed to perform new studies required by the FDA.

The spermicides benzalkonium chloride
Benzalkonium chloride
Benzalkonium chloride, also known as alkyldimethylbenzylammonium chloride and ADBAC, is a mixture of alkylbenzyldimethylammonium chlorides of various even-numbered alkyl chain lengths. This product is a nitrogenous cationic surface-acting agent belonging to the quaternary ammonium group...

 and sodium cholate are used in some contraceptive sponge
Contraceptive sponge
The contraceptive sponge combines barrier and spermicidal methods to prevent conception. Three brands are marketed: Pharmatex, Protectaid and Today. Pharmatex is marketed in France and the province of Quebec; Protectaid in the rest of Canada and Europe; and Today in the United States.Sponges work...

s. Benzalkonium chloride might also be available in Canada as a suppository.

The 2008 Ig Nobel Prize
Ig Nobel Prize
The Ig Nobel Prizes are an American parody of the Nobel Prizes and are given each year in early October for ten unusual or trivial achievements in scientific research. The stated aim of the prizes is to "first make people laugh, and then make them think"...

 (a parody
Parody
A parody , in current usage, is an imitative work created to mock, comment on, or trivialise an original work, its subject, author, style, or some other target, by means of humorous, satiric or ironic imitation...

 of the Nobel Prize
Nobel Prize
The Nobel Prizes are annual international awards bestowed by Scandinavian committees in recognition of cultural and scientific advances. The will of the Swedish chemist Alfred Nobel, the inventor of dynamite, established the prizes in 1895...

s) in Chemistry was awarded to Sheree Umpierre, Joseph Hill, and Deborah Anderson, for discovering that Coca-Cola is an effective spermicide
Spermicide
Spermicide is a contraceptive substance that eradicates sperm, inserted vaginally prior to intercourse to prevent pregnancy. As a contraceptive, spermicide may be used alone. However, the pregnancy rate experienced by couples using only spermicide is higher than that of couples using other methods...

, and to C.Y. Hong, C.C. Shieh, P. Wu, and B.N. Chiang for proving it is not.

Lemon juice solutions have been shown to immobilize sperm in the laboratory, as has Krest Bitter Lemon
Krest
Krest is a soft drink manufactured by The Coca-Cola Company, local to the island of Malta. It was introduced in 1997 in regular and diet versions...

 drink. While the authors of the Krest Bitter Lemon study suggested its use as a postcoital douche, this is unlikely to be effective, as sperm begin leaving the ejaculate (out of the reach of any douche) within 1.5 minutes of deposition. No published studies appear to have been done on the effectiveness of lemon juice preparations in preventing pregnancy, though they are advocated by some as 'natural' spermicides.

Lactic acid
Lactic acid
Lactic acid, also known as milk acid, is a chemical compound that plays a role in various biochemical processes and was first isolated in 1780 by the Swedish chemist Carl Wilhelm Scheele. Lactic acid is a carboxylic acid with the chemical formula C3H6O3...

 preparations have also been shown to have some spermicidal effect, and commercial lactic acid-based spermicides are available. However, no published studies on the effectiveness of lactic acid in preventing pregnancy appear to have been done since 1936. Thomas Moench, a former assistant professor of medicine, has said that research into acids as spermicides has "pretty much been abandoned."

Extractives of the neem
Neem
Azadirachta indica is a tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta, and is native to India growing in tropical and semi-tropical regions. Its fruits and seeds are the source of neem oil...

 plant such as neem oil
Neem oil
Neem oil is a vegetable oil pressed from the fruits and seeds of the neem , an evergreen tree which is endemic to the Indian subcontinent and has been introduced to many other areas in the tropics...

 have also been proposed as spermicides based on laboratory studies. Animal studies of creams and pessaries derived from neem
Neem
Azadirachta indica is a tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta, and is native to India growing in tropical and semi-tropical regions. Its fruits and seeds are the source of neem oil...

 have shown they have contraceptive effects, however trials in humans to determine its effectiveness in preventing pregnancy have not yet been conducted.

Use with condoms

Spermicides are believed to increase the contraceptive efficacy of condoms.

However, condoms that are spermicidally lubricated by the manufacturer have a shorter shelf life and may cause urinary-tract infections in women. The World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

 says that spermicidally lubricated condoms should no longer be promoted. However, they recommend using a nonoxynol-9 lubricated condom over no condom at all.

Side effects

Nonoxynol-9
Nonoxynol-9
Nonoxynol-9, sometimes abbreviated as N-9, is an organic compound that is used as a surfactant. It is a member of the nonoxynol family of nonionic surfactants. N-9 and related compounds are ingredients in various cleaning and cosmetic products. It is widely used in contraceptives for its...

 has a number of possible side effects. These include irritation, itching, or the sensation of burning of the sex organs (either partner), and in women, urinary tract infection
Urinary tract infection
A urinary tract infection is a bacterial infection that affects any part of the urinary tract. Symptoms include frequent feeling and/or need to urinate, pain during urination, and cloudy urine. The main causal agent is Escherichia coli...

s, yeast infection
Candidiasis
Thrush redirects here. For the hoof infection see Thrush .Candidiasis or thrush is a fungal infection of any of the Candida species , of which Candida albicans is the most common...

, and bacterial vaginosis
Bacterial vaginosis
Bacterial vaginosis or less commonly vaginal bacteriosis is a disease of the vagina caused by bacteria. The U.S. Centers for Disease Control and Prevention states it is not clear what role sexual activity plays in the development. However, it is known that BV is associated with having a new sex...

. These side effects are uncommon; one study found that only 3-5% of women who try spermicides discontinue use due to side effects.

Concern has been raised over possible increased risk of birth defects in children conceived despite spermicide use, and also in children of women who, not yet aware of their condition, continued spermicide use during early pregnancy. However, a review in 1990 of large studies on spermicides concluded "there appears to be no increased risk of congenital anomalies, altered sex ratio, or early pregnancy loss among spermicide users."

History

The first written record of spermicide use is found in the Kahun Papyrus
Kahun Papyrus
The Kahun Papyri are a collection of ancient Egyptian texts discussing administrative, mathematical and medical topics. Its many fragments were discovered by Flinders Petrie in 1889 and are kept at the University College London. This collection of papyri is one of the largest ever found. Most of...

, an Egyptian document dating to 1850 BCE. It described a pessary
Pessary
A pessary is a small plastic or silicone medical device which is inserted into the vagina or rectum and held in place by the pelvic floor musculature. - Therapeutic pessaries :...

 of crocodile dung and fermented dough. It is believed that the low pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 of the dung may have had a spermicidal effect.

Further formulations are found in the Ebers Papyrus
Ebers papyrus
The Ebers Papyrus, also known as Papyrus Ebers, is an Egyptian medical papyrus dating to circa 1550 BC. Among the oldest and most important medical papyri of ancient Egypt, it was purchased at Luxor, in the winter of 1873–74 by Georg Ebers...

 from approximately 1500 BCE. It recommended mixing seed wool, acacia, dates and honey, and placing the mixture in the vagina. It probably had some effectiveness, in part as a physical barrier due to the thick, sticky consistency, and also because of the lactic acid
Lactic acid
Lactic acid, also known as milk acid, is a chemical compound that plays a role in various biochemical processes and was first isolated in 1780 by the Swedish chemist Carl Wilhelm Scheele. Lactic acid is a carboxylic acid with the chemical formula C3H6O3...

 (a known spermicide) formed from the acacia.

Writings by Soranus
Soranus (Greek physician)
Soranus was a Greek physician from Ephesus. He practiced in Alexandria and subsequently in Rome, and was one of the chief representatives of the Methodic school of medicine...

, a 2nd century Greek physician, contained formulations for a number of acidic concoctions claimed to be spermicidal. His instructions were to soak wool in one of the mixtures, then place near the cervix.

Laboratory testing of substances to see if they inhibited sperm motility began in the 1800s. Modern spermicides nonoxynol-9 and menfegol were developed from this line of research. However, many other substances of dubious contraceptive value were also promoted. Especially after the prohibition of contraception in the U.S. by the 1873 Comstock Act, spermicides—the most popular of which was Lysol
Lysol
Lysol is a trade name for common household cleanersLysol may also refer to:* Lysol , a 1992 album by The Melvins* Lysol , Actor muMs da Schemer played Lysol in The Mad Real World skit on Chappelle's Show....

—were marketed only as "feminine hygiene" products and were not held to any standard of effectiveness. Worse, many manufacturers recommended using the products as a douche
Douche
A douche is a device used to introduce a stream of water into the body for medical or hygienic reasons, or the stream of water itself.Douche usually refers to vaginal irrigation, the rinsing of the vagina, but it can also refer to the rinsing of any body cavity. A douche bag is a piece of...

after intercourse, too late to affect all the sperm. Medical estimates during the 1930s placed the pregnancy rate of women using many over-the-counter spermicides at seventy percent per year.

Footnotes

Roddy R, Zekeng L, Ryan K, Tamoufe U, Weir S, Wong E. A controlled trial of nonoxynol-9-film to reduce male-to-female transmission of sexually transmitted diseases. N Engl J Med 1998;339:504—10
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