Consult Your Pharmacist (September 1997)
Proper Use of Vaginal Spermicides
The effectiveness of vaginal contraceptives is improved by
a thorough understanding of how to use them properly.
W. Steven Pray, Ph.D., R.Ph.
Professor, Pharmaceutics,
School of Pharmacy,
Southwestern Oklahoma State
University, Weatherford, OK
Pharmacists are often called on to provide information about different
methods of contraception. Patients need several types of information to
allow them to make an informed choice, including failure rates in typical
users, relative costs, protection against sexually transmitted diseases
(STDs) and adverse reactions.
Vaginal spermicides, which use two different mechanisms to prevent
pregnancy, are a viable option for contraception. Their placement in the
vagina produces a barrier to sperm penetration of the cervical os, and the
chemicals in them are directly toxic to sperm. In contrast to agents that must
be taken orally or implanted in the body, vaginal contraceptives are known
as coitally related or episodic products, in that they only need to be used
when sexual activity is imminent.1 Thus, females are not exposed to the
agent throughout the month, as they are with the oral contraceptive,
intrauterine device, implanted insert or depot injection.
In order to be ideal as spermicidal agents, vaginal contraceptives must
meet four criteria:
Act rapidly and effectively, killing all sperm on contact or rendering
them incapable of fertilization
Be systemically nontoxic and nonirri- tating to vaginal and penile skin
and mucosa
Not have any effect on the development of an embryo or fetus
Be free of long-term toxicities.2
While currently available agents have been thought to meet these four
criteria fairly well, they are being examined critically, especially in regard to
their efficacy.
Consumers who understand the proper way to use a vaginal spermicide
may be able to prevent pregnancy. However, used improperly, their
effectiveness is compromised. There is evidence to suggest that properly
informed patients choose spermicides as a part of a total contraception
program. When students in a human sexuality course were educated
appropriately, the percentage of men who would use a spermicide in
addition to a condom grew from 20% to 32%; in females, the percentage
rose from 15% to 26%.3 Students also chose to add a spermicide to a
condom to prevent STDs (rather than use a condom alone) in greater
num-bers than before they took the course.
Mechanism of Action. Vaginal spermicides are surfactant agents.4
Surfactants have been used as contraceptive agents for almost 60 years.
They are thought to act on the midpiece and tail of sperm, directly affecting
the lipid layer, which provides protection to the surface of sperm.2 By
affecting this vital layer of membranes, they cause the sperm to lose motility
and alter their permeability. Additionally, sperm must metabolize fructose to
maintain full activity. Surfactants hamper the fructolytic activity of sperm; it is
a lethal change they cannot survive.
Ingredients Available. Surfactants are classified as ionic, cationic or
nonionic.4 Nonionic sur-factants are most useful for humans. In the United
States, the most commonly used vaginal spermicide is the neutral agent
nonoxynol-9. However, octoxynol is also fully approved by the FDA. In other
parts of the world, the surfactants benzalkonium chloride (cationic) and
docusate sodium (anionic) are also used for contraception.4
Advantages. In surveys of spermicide users, women say they appreciate
spermicidal products because they not only prevent conception, but
improve sexual satisfaction and are convenient to use. Women also believe
that they prevent sexually transmitted diseases.5 Male users also list these
features and appreciate the additional lubrication the products provide.
Inadequate lubrication during sexual activity is a major factor causing
rupture of condoms; vaginal spermicides that contribute to vaginal
lubrication reduce risk of pregnancy and STDs.
Adverse Reactions to Vaginal Spermicides. Used according to
directions, vaginal spermicides are usually free of adverse effects. They
have been available for over 40 years; the relative paucity of reports is
testimony to a low incidence of adverse reactions. However, several
problems are covered in the medical literature.
ú Vaginal Irritation. The detergent effect of vaginal spermicides can
produce vaginal irritation.11 Prostitutes, who tend to use greater amounts of
the product, report fairly high incidences of both vaginal and oral irritation
with spermicidally lubricated condoms.9 Vaginal soreness and irritation of
the penis are also possible. At higher concentrations than those that are
available commercially, vaginal spermicides may produce lesions and
ulcerations of vaginal epithelium.4,9,12
It is possible that spermicides will never be able to reduce the risk of STDs
such as HIV in vivo since vaginal and cervical mucosal damage may
actually enhance the risk of STD transmission.10 Further, if vaginal irritation
becomes too troublesome, compliance will diminish, increasing the risk of
conception.13 Fortunately, at commercially available concentrations, vaginal
irritation is not a common adverse reaction.
ú Vaginal Infections. Vaginal spermicides can potentially disrupt the
vaginal ecology since various organisms constituting normal vaginal
microflora have differing susceptibilities to the detergent effect of the
spermicides.
Spermicides may increase the risk of urogenital infection through two
mechanisms.9 The first is direct toxicity for lactobacilli. Lactobacilli in the
vaginal vault are hypothesized to perform a barrier function against infection
of the vaginal, perineal and urethral areas, perhaps through production of
hydrogen peroxide. Nonoxynol is directly toxic to lactobacilli in
concentrations as dilute as 0.1%. By contrast, uropathogenic organisms
such as Proteus mirabilis, Staphylococcus, E. coli, and Proteus mirabilis
survive concentrations of nonoxynol as high as 25%. Therefore, use of
spermicides may indirectly promote the growth of these organisms by
acting against lactobacilli. Candida albicans and other organisms that
cause vaginal fungal infection also survive high concentrations of
nonoxynol.9 When used in conjunction with a diaphragm, vaginal
spermicides have been implicated in asymptomatic bacteriuria, E. coli
vaginal colonization, and an increase of up to four times in the risk of urinary
tract infections.9
ú Allergic Reactions. Patients may also experience contact dermatitis to
spermicides.9 In one case, a female experienced a pruritic rash of unknown
origin.14 The rash was thought to be coitally related since it only manifested
24-48 hours following coitus with her partner. As physicians explored
possible causes, they discovered that the rash occurred in areas most often
caressed by her partner during sexual activity. The male applied
spermicidally lubricated condoms just prior to sex, and did not wash
residual spermicide from the hands. Although the patient refused
confirmatory testing, the authors hypothesized the allergy was due to the
spermicide (texafor, not available in the U.S.) or a perfuming agent.
ú Teratogenicity. A congressional hearing raised the issue of possible
teratogenicity and carcinogenicity of spermicides.15 Pending resolution of
the question, the FDA advised that it would examine the issue, but
eventually decided that sufficient evidence of teratogenicity was lacking.
Duration of Activity. A major consideration for the female is the duration
of contraceptive activity of the various preparations. A relatively recent
agent is one of the few 24-hour nonprescription products available. Known
as Advantage 24, it remains on the vaginal surface for a maximum of 72
hours, although the company only labels it for a 24-hour duration.13 Its long
duration may increase the riskof vaginal irritation. However, in research, the
product was better tolerated than a spermicidal suppository.
Current FDA Viewpoint Regarding Vaginal Spermicides. In 1995, the
FDA notified manufacturers that companies marketing spermicides would
be required to obtain approved applications for all products since
effectiveness would be critically dependent on the final formulation.15
Testing under actual conditions of use would determine whether the
effectiveness of the products is unduly compromised when genital
secretions dilute them.
Teen Misconceptions. The pharmacist who counsels teen users of
contraceptives must be prepared to engage in frank discussion with a
confused, possibly embarrassed patient. In one case, a physician carrying
out a routine pelvic exam on a young patient noticed her vaginal secretions
were tinged an unnatural purple color. The teen had used a grape jelly,
thinking that what she heard about vaginal contraceptive jelly was just that:
jelly. The pharmacist is obviously in an ideal clinical setting to teach teens
about the value of abstinence and provide instructions about confusing
products such as vaginal jellies, both before they are needed and at the
point of sale.
Spermicides and Protection Against
Sexually Transmitted Diseases
General Precautions Regarding STDs
Vaginal contraceptives can never guarantee against contracting a sexually transmitted
disease (STD). The best defense against this is abstinence prior to a mutually monogamous
relationship in which neither partner is infected with an STD or uses IV drugs. However,
many people fall short of this ideal.
Condoms are perhaps the next best method for STD prevention, but women are not able to
initiate condom use in many ethnic groups due to cultural taboos, and condom rupture is a
risk of usage.6,7 Therefore, it is prudent to examine vaginal contraceptives in regard to their
potential to prevent STDs.
Potential Spermicidal Activity Against STDs
Any discussion of the capabilities of a group of contraceptive products must also take into
consideration their ability to block the transmission of STDs. The detergent action of
spermicides is thought to be virucidal through the same mechanisms by which they destroy
sperm, dissolving the lipid components of the viral envelope.4
Nonoxynol-9 has been found experimentally to be virucidal in vitro against herpes simplex
virus type 2 and HIV type 1.8 The molecule acts against various other organisms
responsible for STDs, such as Treponema pallidum, Neisseria gonorrhoea, Trichomonas
vaginalis and Candida albicans.4,9 However, the use of a spermicide will not cure
pre-existing infections from these organisms. Further, as the majority of this work was
experimental, it is not known what activity the products actually have in the genital tract.
Thus, the FDA does not allow labeling indicating activity against STDs. Despite this, one
journal article states, spermicides "have been widely recommended for the prevention of HIV
transmission..."10
Patient Information
Vaginal Spermicides and Birth Control
Vaginal spermicides (nonoxynol, octoxynol) work by destroying sperm in the vagina.
Women may use a vaginal contraceptive foam, jelly or suppository as the sole agent for
contraception, although some products recommend use with a diaphragm. Spermicides
are also used with the cervical cap. Also, nonoxynol is added to some condoms, which
may be advertised as "spermicidally lubricated." In order to destroy sperm adequately,
spermicides must be used correctly. It is critical that you have read all of the
manufacturer's directions. You should have read them completely before it is time to use
them. Because vaginal spermicides are often used incorrectly, they typically produce 21
pregnancies per 100 women per year compared to condoms (only 12 pregnancies per
100 women per year). Should you wish to use a more effective contraceptive, see a
physician for a prescription product, such as an oral contraceptive.
General directions for the different products follow. You should also read specific product
instructions carefully.
Foams (e.g., Emko, Delfen): Shake the can well before use to mix the ingredient with the
foam, then fill the applicator as directed. Insert the foam deeply in the vagina up to one hour
before sexual activity. Another dose should be inserted for another act. Wait at least six
hours after the male ejaculates before douching.
Jellies (e.g., Advantage 24, Conceptrol, Gynol II, KY Plus): Use a pre-loaded
applicator or load the applicator as directed. Use with a diaphragm if the product label
indicates that you should do so. Insert the jelly and begin intercourse within one hour. Do
not douche for six hours. A newer product known as Advantage 24 can be inserted any
time up to 24 hours before sexual activity, since it is active for a much longer period than
other products.
Suppositories (e.g., Conceptrol, Encare, Semicid): These products must not be
inserted in the urinary opening (urethra). If you do so, see a physician at once. Unwrap and
insert the suppository into the vaginal opening following the illustrations included with the
product. Insert 10-15 minutes (but not more than one hour) prior to sexual activity, as
directed on the box. Use another suppository for another act or if more than one hour has
elapsed since insertion. Do not douche for six hours.
You may need to try several products before finding one that is satisfactory. Suppositories
were found less acceptable to females in one study because they provided too much
lubrication and caused discomfort, pain or itching. Foams produced too much messiness
or a vaginal discharge, according to females. Males found foams produced too much
lubrication, discomfort, pain or itch, and reported that suppositories caused excess
lubrication, discomfort, pain or itch, and were awkward or inconvenient to use.
These directions apply only to prevention of pregnancy. The products cannot guarantee
protection against sexually transmitted diseases, such as herpes, AIDS, gonorrhea, etc.
Only abstinence or sexual activity with an uninfected partner can provide this assurance. |
