Biology:Spermicide

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Short description: Contraceptive that destroys sperm
Spermicide
Background
TypeSpermicide
First useAncient
Failure rates (first year)
Perfect use6%
Typical use16%[1]
Usage
ReversibilityImmediate
User remindersMore effective if combined with a barrier method
Advantages and disadvantages
STI protectionNo
Weight gainNo
BenefitsProvides lubrication

Spermicide is a contraceptive substance that destroys 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. Usually, spermicides are combined with contraceptive barrier methods such as diaphragms, condoms, cervical caps, and sponges. Combined methods are believed to result in lower pregnancy rates than either method alone.[2]

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

Types and effectiveness

The most common active ingredient of spermicides is nonoxynol-9. Spermicides containing nonoxynol-9 are available in many forms, such as jelly (gel), films, and foams. Used alone, spermicides have a perfect use failure rate of 6% per year when used correctly and consistently, and 16% failure rate per year in typical use.[1]

Spermicide brands

This list of examples was provided by the Mayo Clinic:[3]

  1. VCF Vaginal Contraceptive Film
  2. VCF Vaginal Contraceptive Gel
  3. VCF Contraceptive Foam
  4. Conceptrol
  5. Crinone
  6. Encare
  7. Endometrin
  8. First-Progesterone VGS
  9. Gynol II
  10. Prochieve
  11. Today Sponge
  12. Vagi-Gard Douche Non-Staining

Nonoxynol-9 is the primary chemical in spermicides to inhibit sperm motility. Active secondary spermicidal ingredients can include octoxynol-9, benzalkonium chloride and menfegol.[4] These secondary ingredients are not mainstream in the United States, where nonoxynol-9 alone is typical. Preventing sperm motility will inhibit the sperm from travelling towards the egg moving down the fallopian tubes to the uterus. The deep proper insertion of spermicide should effectively block the cervix so that sperm cannot make it past the cervix to the uterus or the Fallopian tubes. A study observing the distribution of spermicide containing nonoxynol-9 in the vaginal tract showed “After 10 min the gel spread within the vaginal canal providing a contiguous covering of the epithelium of variable thickness.”[5] The sole goal of spermicide is to prevent fertilization.

Menfegol is a spermicide manufactured as a foaming tablet.[6] 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.[7]

The spermicides benzalkonium chloride and sodium cholate are used in some contraceptive sponges.[8] Benzalkonium chloride might also be available in Canada as a suppository.[9]

The 2008 Ig Nobel Prize (a parody of the Nobel Prizes) in Chemistry was awarded to Sheree Umpierre, Joseph Hill, and Deborah Anderson, for discovering that Coca-Cola is an effective spermicide,[10] and to C.Y. Hong, C.C. Shieh, P. Wu, and B.N. Chiang for proving it is not.[11][12]

Lemon juice solutions have been shown to immobilize sperm in the laboratory,[13] as has Krest Bitter Lemon drink.[14] 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.[15]

Lactic acid preparations have also been shown to have some spermicidal effect, and commercial lactic acid-based spermicides are available.[16][17] A contraceptive containing lactic acid, citric acid, and potassium bitartrate (Phexxi) was approved for use in the United States in May 2020.[18]

Extractives of the neem plant such as neem oil have also been proposed as spermicides based on laboratory studies.[19] Animal studies of creams and pessaries derived from neem have shown they have contraceptive effects;[20] 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 effectiveness of condoms.[2]

However, condoms that are spermicidally lubricated by the manufacturer have a shorter shelf life[21] and may cause urinary tract infections in women.[22] The World Health Organization says that spermicidally lubricated condoms should no longer be promoted. However, they recommend using a nonoxynol-9 lubricated condom over no condom at all.[23]

Spermicides used alone are only about 91 percent effective.[24] When spermicides are used in conjunction with condoms and other barrier methods there is a 97 percent effective rate for pregnancy prevention.

Side effects

Temporary local skin irritation involving the vulva, vagina, or penis is the most common problem associated with spermicide use.[25]

Frequent use (two times or more a day) of nonoxynol-9 containing spermicide is inadvisable if STI/HIV exposure is likely, because in this situation there is increased vulvovaginal epithelial disruption and increased risk of HIV acquisition.[25]

In 2007, the United States Food and Drug Administration (FDA) mandated that labels for nonoxynol-9 over-the-counter (OTC) contraceptive products carry a new warning saying they do not protect against STDs and HIV/AIDS.[26][27]

History

The first written record of spermicide use is found in the Kahun Papyrus, an Egyptian document dating to 1850 BCE. It described a pessary of crocodile dung and fermented dough.[28] It is believed that the low pH of the dung may have had a spermicidal effect.[29]

Further formulations are found in the Ebers Papyrus 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 (a known spermicide) formed from the acacia.[29]

Writings by Soranus, 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.[28]

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.[28] 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—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 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.[30]

A misconception about spermicides existed in the 1980s and 1990s. A 1988 literature review article noted that in vitro studies of nonoxynol-9 and other spermicides showed inactivation of STI pathogens, including HIV.[31] But a 2002 systemic review and meta-analysis of nine randomized controlled trials of vaginal nonoxynol-9 for HIV and STI prevention involving more than 5,000 women (predominantly sex workers) found no statistically significant reduction in risk of HIV and STIs, but found a small statistically significant increase in genital lesions among nonoxynol-9 spermicide users.[32] And in a high-risk population using a nonoxynol-9 vaginal gel more than three applications per day on average, the risk of HIV acquisition was increased.[25]

See also

  • Personal lubricant
  • Contraceptive sponge

References

  1. ↑ 1.0 1.1 Grimes, David A; Lopez, Laureen M; Raymond, Elizabeth G.; Halpern, Vera; Nanda, Kavita; Schulz, Kenneth F (30 September 2013). Halpern, Vera. ed. "Spermicide used alone for contraception". Cochrane Database of Systematic Reviews (12): CD005218.pub3. doi:10.1002/14651858.CD005218.pub4. PMID 24307556. 
  2. ↑ 2.0 2.1 "Efficacy of the simultaneous use of condoms and spermicides". Fam Plann Perspect 23 (5): 226–7, 232. 1991. doi:10.2307/2135759. PMID 1743276. 
  3. ↑ Clinic, Mayo. "Spermicide (Vaginal Route)". Mayo Clinic. http://www.mayoclinic.org/drugs-supplements/spermicide-vaginal-route/description/drg-20070769. 
  4. ↑ World Health Organization. "WHO/Conrad Technical Consultation". Geneva. http://whqlibdoc.who.int/hq/2003/WHO_RHR_03.08.pdf. 
  5. ↑ Barnhart, K.T. (1 June 2001). "Distribution of a spermicide containing Nonoxynol-9 in the vaginal canal and the upper female reproductive tract". Human Reproduction 16 (6): 1151–1154. doi:10.1093/humrep/16.6.1151. PMID 11387285. 
  6. ↑ "Spermicides: Neo-Sampoon (Menfegol)". RemedyFind. http://www.remedyfind.com/treatments/77/1301/. 
  7. ↑ "Status of Certain Additional Over-the-Counter Drug Category II and III Active Ingredients". Federal Register. Food and Drug Administration. May 9, 2002. https://www.fda.gov/ohrms/dockets/98fr/050902b.htm. 
  8. ↑ "Sponges". Cervical Barrier Advancement Society. 2004. http://www.cervicalbarriers.org/information/sponges.cfm. 
  9. ↑ "Spermicides (Vaginal)". MayoClinic.com. August 1997. http://www.mayoclinic.com/health/drug-information/DR202531. 
  10. ↑ Umpierre, Sharee A.; Hill, Joseph A.; Anderson, Deborah J. (21 November 1985). "Effect of 'Coke' on sperm motility.". The New England Journal of Medicine 313 (21): 1351. doi:10.1056/NEJM198511213132111. PMID 4058526. 
  11. ↑ Hong, C.Y.; Shieh, C.C.; Wu, P.; Chiang, B.N. (September 1987). "The spermicidal potency of Coca-Cola and Pepsi-Cola". Human Toxicology (Macmillan Publishers, Scientific and Medical Division) 6 (5): pp. 395–6. doi:10.1177/096032718700600508. PMID 3679247. 
  12. ↑ Mikkelson, Barbara (March 16, 2007). "Killer Sperm: Coca-Cola Spermicide". http://www.snopes.com/cokelore/sperm.asp. 
  13. ↑ Roger Short; Scott G. McCoombe; Clare Maslin; Eman Naim; Suzanne Crowe (2002). Lemon and Lime juice as potent natural microbicides. http://www.aids.net.au/aids-lemons.pdf. Retrieved 2006-08-13. 
  14. ↑ Nwoha P (1992). "The immobilization of all spermatozoa in vitro by bitter lemon drink and the effect of alkaline pH". Contraception 46 (6): 537–42. doi:10.1016/0010-7824(92)90118-D. PMID 1493713. 
  15. ↑ "MoonDragon's Contraception Information: Spermicides". MoonDragon Birthing Services. c. 1997. http://www.moondragon.org/obgyn/contraception/spermicides.html. 
  16. ↑ "Femprotect - Lactic Acid Contraceptive Gel". Woman's Natural Health Practice. http://www.naturalgynae.com/nav6_fact19.html. 
  17. ↑ Stone H (1936). "Contraceptive jellies: a clinical study". J Contracept 1 (12): 209–13. PMID 12259192. 
  18. ↑ "U.S. FDA Approves Evofem Biosciences' Phexxi (lactic acid, citric acid and potassium bitartrate), the First and Only Non-Hormonal Prescription Gel for the Prevention of Pregnancy". Evofem Biosciences (Press release). 22 May 2020. Retrieved 22 May 2020 – via PR Newswire.
  19. ↑ "Mechanism of action of NIM-76: a novel vaginal contraceptive from neem oil". Contraception 54 (6): 373–8. 1996. doi:10.1016/S0010-7824(96)00204-1. PMID 8968666. 
  20. ↑ "Plant immunomodulators for termination of unwanted pregnancy and for contraception and reproductive health". Immunol Cell Biol 75 (2): 190–2. 1997. doi:10.1038/icb.1997.27. PMID 9107574. 
  21. ↑ "Spermicide (Nonoxynol-9)". Other disadvantages. http://www.condomjungle.com/Spermicidal_Nonoxynol_9_Lubricated_Condoms_s/61.htm. 
  22. ↑ "Condoms: Extra protection". ConsumerReports.org. February 2005. http://www.consumerreports.org/cro/health-fitness/health-care/condoms-and-contraception-205/overview/index.htm. 
  23. ↑ WHO (2002). "HIV/AIDS Topics: Microbicides". Geneva: World Health Organization. https://www.who.int/hiv/topics/microbicides/microbicides/en/. 
  24. ↑ WebMD. "Spermicide for Birth Control - Topic Overview". http://www.webmd.com/sex/birth-control/tc/spermicide-for-birth-control-topic-overview. 
  25. ↑ 25.0 25.1 25.2 Cates, Willard Jr.; Harwood, Bryna (2011). "Vaginal Barriers and Spermicides". in Hatcher, Robert A.; Trussell, James; Nelson, Anita L. et al.. Contraceptive Technology (20th revised ed.). New York: Ardent Media. pp. 391–408. ISBN 978-1-59708-004-0. OCLC 781956734.  p. 399:

    Currently available spermicides containing nonoxynol-9 are ineffective as microbicides, in particular as HIV-preventive measures.17 Thus, spermicides used alone are not recommended to prevent HIV or other STIs. Furthermore, frequent use (more than 2 times a day) of spermicide causes more vulvovovaginal epithelial disruption,18 which theoretically could increase susceptibility to HIV. In a high-risk population using a vaginal gel with nonoxynol-9 more than three applications per day on average, the risk of HIV acquisition was increased compared with placebo.19

    p.399–400:

    Disadvantages and cautions
    Local irritation
    Temporary skin irritation involving the vulva, vagina, or penis caused by either local toxicity or allergy to the formulation is the most common problem associated with spermicide use... Although vaginal epithelial disruption has been associated with frequent use (twice a day or more) of spermicides containing N-9, this is usually asymptomatic. In a low risk population, long-term use of N-9 containing methods was not associated with epithelial disruption.22

    p. 401:

    N-9 spermicides are inadvisable if STI/HIV exposure is likely in situations that would involve frequent use defined as 2 times or more a day.
  26. ↑ FDA (December 18, 2007). "FDA mandates new warning for nonoxynol 9 OTC contraceptive products. Label must warn consumers products do not protect against STDs and HIV/AIDS (news release)". Silver Spring, Md.: Food and Drug Administration. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2007/ucm109043.htm. 
  27. ↑ FDA (December 19, 2007). "Final rule. Over-the-counter vaginal contraceptive and spermicide drug products containing nonoxynol 9; required labeling". Federal Register 72 (243): 71769–71785. https://www.fda.gov/OHRMS/DOCKETS/98fr/07-6111.htm. 
  28. ↑ 28.0 28.1 28.2 "Evolution and Revolution: The Past, Present, and Future of Contraception". Contraception Online (Baylor College of Medicine) 10 (6). February 2000. http://www.contraceptiononline.org/contrareport/article01.cfm?art=93. 
  29. ↑ 29.0 29.1 Towie, Brian (January 19, 2004). "4,000 years of contraception on display in Toronto museum". torontObserver. Centennial College journalism students. http://observer.thecentre.centennialcollege.ca/features/condom_museum011904.htm. 
  30. ↑ Tone, Andrea (1996). "Contraceptive Consumers: Gender and the Political Economy of Birth Control in the 1930s". Journal of Social History 29 (3): 485–506. doi:10.1353/jsh/29.3.485. Gale A18498205. 
  31. ↑ Feldblum, P J; Fortney, J A (January 1988). "Condoms, spermicides, and the transmission of human immunodeficiency virus: a review of the literature.". American Journal of Public Health 78 (1): 52–54. doi:10.2105/ajph.78.1.52. PMID 3276230. 
  32. ↑ Wilkinson, David; Tholandi, Maya; Ramjee, Gita; Rutherford, George W. (October 2002). "Nonoxynol-9 spermicide for prevention of vaginally acquired HIV and other sexually transmitted infections: systematic review and meta-analysis of randomised controlled trials including more than 5000 women". Lancet Infectious Diseases 2 (10): 613–617. doi:10.1016/S1473-3099(02)00396-1. PMID 12383611. 



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