Contraception

Vaginal Spermicide

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Vaginal Spermicide, Spermicide, Nonoxynol

  • Indications
  1. Use with contraceptive barrier methods
    1. Cervical Cap
    2. Contraceptive Diaphragm
  • Preparations
  1. Nonoxynol-9 (Gynol II)
    1. Shortens Condom shelf life and is more costly
    2. Highest concentration (150 mg) is most efficacious
      1. Failure rate is still 14% at 150 mg
      2. Overall failure rate for all concentrations: 22%
      3. Raymond (2004) Obstet Gynecol 103:430-9 [PubMed]
    3. Do not use for STD protection
      1. Does not increase Condom efficacy
      2. Does not protect against Gonorrhea and Chlamydia
        1. Roddy (2002) JAMA 287:1117-22 [PubMed]
      3. Increases risk of Gonorrhea
        1. Richardson (2001) Sex Transm Dis 28:394-400 [PubMed]
      4. Increases HIV risk (disrupts vaginal epithelium)
    4. References
      1. Apgar (2003) AAFP Board Review, Seattle
  2. Octoxynol-9
  3. Benzalkonium
  4. Phexxi
    1. Contains Lactic Acid, citric acid and Potassium bitartrate
    2. Marketed as a "vaginal contraceptive gel" but it is simply a Spermicide
    3. No more effective than other barrier methods (14% will become pregnant in 7 months)
    4. Very expensive ($270 per 12 applicators)
    5. One applicator intravaginally up to 1 hour before intercourse and must be reapplied for each episode
    6. Does not protect against STDs (use Condoms)
    7. (2020) presc lett 27(9): 52
  5. Homemade Spermicide (anecdotal with unproven efficacy)
    1. Aloe Vera Gel: 1 Tablespoon
    2. Lemon juice: 3 drops
    3. Keep refrigerated for no longer than 72 hours
    4. Reference
      1. Summerhayes (1999) CMEA Women's Health, San Diego
      2. Oyelola (1987) Contraception 36(4):435-40 [PubMed]
  • Mechanism
  1. Spermicide attacks sperm acrosomal membranes
  2. Breakdown of membranes immobilizes sperm
  3. Spermicide delivered in base to adhere to Cervix
  • Efficacy
  1. Overall Failure rate: 21% (3-31%)
  • Technique
  1. Allow time for activation and well timed for sex
  2. Reapply Spermicide for repeat intercourse
  3. No douching for 6 hours post intercourse
  • Disadvantages
  1. Sex may need to be interrupted to apply
  2. Messy or difficult to apply
  3. Unpleasant smell or taste
  • Adverse Effects
  1. Allergy to Spermicide in 2-4% of men and women