- When used correctly and consistently, condoms are an effective means of preventing pregnancy. Pregnancy rates for condoms range from 3 percent to almost 14 percent. This means 3 to 14 out of 100 women get pregnant in a year using only condoms for contraception. However, these pregnancies are not due primarily to condom failure. Higher pregnancy rates during typical condom use reflect inconsistent and incorrect use. Non-use, i.e., inconsistent use, is particularly dramatic. If a women does not use a condom during just one fertile phase in a year, she has a four-times higher risk of becoming pregnant than if she uses condoms consistently and experiences occasional breakage. Moreover, the risk of breakage is concentrated in certain couples. This means that the majority of couples who use condoms consistently are at very low risk, at least of pregnancy.
- When used correctly and consistently, condoms are an effective means of preventing STD/HIV. The equation is somewhat different for STDs than for pregnancy. The fertile period is intermittent, but individuals can be at risk of contracting an STD or HIV at every intercourse. Study after study has shown that condoms are extremely effective against STD/HIV if they are used consistently and correctly. In many cases couples do not know one another's HIV or other STD status. In these instances, not all partners are infected, and intermittent condom use will provide protection against transmission in a proportion of cases. However, if one partner is HIV-positive, then there is a guaranteed risk of exposure to infection at every unprotected intercourse, and inconsistent condom use offers little protection against HIV, compared with non-use.
- Latex condoms provide an impermeable mechanical barrier. Latex condoms are virtually impermeable to viruses and to sperm. Therefore, unless a condom breaks or completely slips off in a clinically significant manner, i.e. during or after ejaculation, or has a pinhole which is extremely rare, users are not exposed to semen or viral particles.* Broken or leaky condoms certainly expose women to semen and viruses, and expose men to infection from women, but on average, non-use of condoms exposes individuals to a far higher magnitude of risk.
- Most users do not break condoms, and a proportion of breakage is preventable. Most people who use condoms, especially once they gain experience with them, rarely experience breakage or slippage; condom failure is actually concentrated among a small percentage of users. Studies have identified characteristics of condom users that seem to be associated with more frequent condom breakage and slippage. A history of condom failure and inexperience in using condoms are the characteristics most strongly associated with condom failure. Some research also suggests that young age, not living with one's sexual partner, low level of education, having multiple sexual partners, low income and large penis size are also correlated with increased risk of condom breakage and/or slippage.
Studies also suggest that certain behaviors are associated with increased breakage and/or slippage including: improper storage, rough handling of condoms, improper donning techniques, not encouraging natural vaginal lubrication, using excessive added lubricants (especially oil-based), lengthy or vigorous sex, anal or oral intercourse, loss of erection prior to withdrawal, and re-use of condoms.
Since correct condom use is both a taught and a learned behavior, it is evident why these variables are related to condom failure, and how some might be reduced or prevented through improved education and counseling. Obvious problems like opening condom packages with sharp objects, and pre-stressing them by unrolling, stretching, or "water testing" before use can be avoided if condom users are told that such actions increase the chances of condom failure. Use of appropriate lubricant is also important to reduce the risk of breakage. Intensive one-to-one counseling of all condom users is not likely to be feasible, however, because it is labor intensive and expensive, so it remains a priority to identify the behaviors which most frequently lead to breakage and slippage and target broad education efforts at those.
Also, counseling may not help couples for whom condoms regularly break or slip off because he has a large penis, she has a small vagina, she has little vaginal lubrication, or their intercourse is especially vigorous or prolonged (although, counseling might at least identify the nature of their problem with condoms). Some breakage may be prevented by using additional water-based lubricant during lengthy intercourse. Or the couple might be advised to extend foreplay until the woman is more aroused, or put on a new condom and discard the first one before intercourse is completed. Nevertheless, some anatomical challenges of using condoms might ultimately have to be overcome through improved condom design. We do not know whether these potential solutions have any merit because we have a very incomplete understanding of the detailed dynamics of human use of condoms.
- Today's condom is manufactured with greater precision. An additional reason for users and reproductive health programs to have confidence in modern condoms is that latex condoms are better formulated, processed, finished and packaged than they have ever been in the past. During formulation there is now far greater control exerted over the chemical processes of oxidation and vulcanization, which reduces the risk of condom failure due to aging. Also, enough is known about the impact of condom modulus and stress and strain properties on performance during human use to enable manufacturers to optimize these properties by adjusting the latex formulation. In recognition of the growing problem of latex allergy, condom manufacturers make greater efforts to remove latex protein allergens during processing. Manufacturers are also aware of the potential risk posed from using talc as a dry lubricant and seem to have shifted to cornstarch. However, since cornstarch may not be entirely without risk, the search for a better and safer dry finishing powder continues.
- Condoms use is improved by the right lubricant. Wet lubricants placed on finished condoms prior to packaging include water-based lubricants, alone or with spermicide added, and liquid silicone. The evidence suggests that using appropriate quantities of the right types of lubricant (in manufacturing and/or at the time of use) decreases breakage and increases satisfaction with condoms. Use of water-based lubricants may increase slippage, but data suggest that the protective effect against breakage may outweigh any risk of increased slippage.
There is no evidence that spermicidally lubricated condoms confer any advantage by increasing efficacy against pregnancy or disease, in spite of a consumer perception that spermicidal lubricant ought to do this. Condom marketing that promotes this misperception should be discouraged. Indeed, there is some preliminary evidence that spermicidal lubrication may promote leaching of latex allergens, thereby increasing the risk of allergy. Since spermicidally lubricated condoms also have a shorter designated shelf life, silicone is a preferable lubricant.
- Condoms in intact foil packages last at least five years on the shelf. Recent data indicate that adequate packaging is crucial to the long-term integrity of latex condoms. Plastic packages expose condoms to greater and more rapid deterioration from oxidation, humidity, ozone and ultraviolet light than do foil packages. When properly sealed in foil packages, modern latex condoms are quite resistant to adverse environmental conditions and will retain their quality for at least five years and probably longer. Thus all condoms should be packaged in aluminum foil, or foil-plastic laminate packages.
- Production quality control and post-production quality assurance help ensure a reliable product enters the marketplace. In addition to many specific improvements in all aspects of latex condom manufacture, an extensive system of internal and external quality control and quality assurance is now in place to ensure latex condoms are of high quality. In the era of AIDS, the condom is considered a potentially life-saving medical device, and as such is subject to strict quality standards. Through both worldwide (the ISO) and regional standards bodies (the ASTM and CEN), minimum acceptable quality levels are set and enforced to permit manufactured products to enter the market. Some standards are enforceable by law, and others represent consensus guidelines.
In spite of the deliberate, and therefore often slow, nature of cross-national standard setting, there is now considerable uniformity across the three major standards agencies. Also, the world's two major procurement specifications, those of USAID and WHO, are the impetus behind additional measures designed to ensure product acceptability to service delivery programs and end users.
Neither standards nor specifications can protect condom users from poor quality devices that are manufactured without adequate quality assurance, or are tested in sub-standard laboratory facilities. However, the wide net cast by current standards bodies ensures that the great majority of condoms, in the majority of countries (including condoms supplied by international donors), are manufactured to a high standard.
- While it is not yet clear how well the test standards predict results during human use, a combination of tests can provide clear guidance on the quality of condoms in the field. The current battery of tests -- condom dimensions, package integrity, lubricant quantity, water leakage, tensile properties, and air burst properties -- assure that newly manu-factured condoms conform to international standards and specifications. But uncertainty still surrounds the validity of these tests in assessing condom deterioration over time and predicting performance in human use.
For example, the tensile test provides valuable information on latex formulation and manufacturing uniformity, but because it measures a segment from the middle of the condom that is the least challenged during sexual intercourse, it is not a very good predictor of condom failure in human use. The air burst test, on the other hand, has accurately predicted human use breakage in some studies. In other studies, the age of the con-dom has been the best predictor of breakage. Unfortunately, good data are limited, and the few studies that have been done pre-date improvements in latex manufacture and packaging. Thus it is likely that new research would show less deterioration over time due to in-package oxidation and vulcanization, or poor package integrity.
For the time being, programs in the field wishing to assess possible condom deterioration posing a high risk of failure in human use will have to rely on a combination of condom age and the air burst, package integrity and lubricant tests. No single laboratory test is an adequate surrogate for condom performance during use.
- Various synthetic alternatives to latex condoms show promise for expanding condom acceptability and use. In time, condoms made of synthetic materials may replace latex in part or altogether. Synthetic condoms made from thermoplastic elastomers have several advantages over latex. They have more controllable physical properties such as strength and can be fashioned in any shape and size. They may transmit heat better than latex, allowing for greater sensitivity during intercourse. They usually do not have an odor, as latex can; do not deteriorate with oil-based lubricants; and do not produce allergic reactions. They are more uniform in composition than latex and may not deteriorate in the same way under adverse storage conditions.
Further, synthetic condoms can be designed for use by men or women -- male or female condoms. This marks a genuine breakthrough for reproductive health programs because couples have a real alternative when negotiating whether or not to use a condom; they can use either type of condom. One study has shown that when both male and female condoms are offered as part of a safer sex strategy more sex acts are protected overall, by one or the other device.
Several non-latex male condoms have received FDA approval for marketing as hypoallergenic to latex, and one female condom has received approval for marketing for pregnancy and disease control as well. However, the only two currently being sold are the Avanti male condom (London International Group) and the female condom (Female Health Company). Even though alternatives to latex condoms may receive expedited FDA review and approval, the product development process is long and involved, and new products are slow to enter the market. Unfortunately, the limited availability and high cost of synthetic condoms relative to latex mean that most consumers are going to have to rely on latex condoms for the foreseeable future.
*During vaginal intercourse condoms only form a barrier between the skin of the penis and the skin of the vagina. Some sexually transmitted viruses such as HPV can be transmitted via skin-to-skin contact between the scrotal skin and the perineum. Therefore, even intact condoms cannot prevent the transmission of all organisms. Devices such as the female condom which cover more of the external genitalia may afford greater protection.
by Erin T. McNeill
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