Historically, coitus interruptus and barrier methods are the oldest conscientious attempts at preventing unwanted conception.¹² Barrier contraceptives and spermicides may be defined as the contraceptive techniques that prevent sperm from being released in the vagina or that can immobilize sperm or have lethal activity against them (Table 1). This may be achieved by either mechanical or chemical means. Barrier and spermicidal methods of contraception are coitus-dependent; all are temporally associated with sexual intercourse. Except for the male condom and coitus interruptus, all are female-dependent methods.

Table 1. Barrier Contraceptive Methods and Spermicides

The decision to comply with a preventive measure such as contraception depends on the perceived risk of becoming pregnant, the desire to avoid pregnancy, and numerous other factors, such as the need for confidentiality, adverse side effects, ambivalence, difficulty making decisions at every sexual engagement, and naïveté regarding how a contraceptive works, fear of infections, and misgivings about the general effects of contraceptives. In most cases, the successful use of barrier methods necessitates a change in sexual behavior.^7,8,9

Barrier contraceptives are very safe. They are used inconsistently more often than noncoitus-dependent methods.¹⁰ Some are relatively complicated to use and involve a complex series of sequential steps, so the chances for incorrect use are high. Any condition that limits manual dexterity or the ability to follow sequential directions may limit their consistent use and effectiveness. Barrier contraceptive methods are the only ones currently recommended for the prevention of STDs and HIV, making them important for ensuring reproductive health. Finally, barrier contraceptives make an important contribution to family planning and public health because they are safe, have no systemic side effects or risks, are reasonably effective, and play a prominent role in the prevention of STDs. Some, such as spermicides and condoms, necessitate no professional participation for their popularization and correct use.^6,7,8,9,10

Barrier methods are reputed to be less effective than other methods. This applies only to spermicides used alone; however, they have a significant historical role in the process of making contraception universally available.¹² Most of them can be distributed easily through community-based organizations and women's health maintenance groups, and in developing countries by social marketing programs through existing commercial outlets. They extend the accessibility of reliable contraceptives to a greater number of people than ordinarily would be reached by the formal healthcare system.

There are two measures of how a contraceptive works: efficacy (how it performs under ideal conditions, perfect use) and effectiveness (how well it works under typical use).¹³ Contraceptive effectiveness depends on many factors: frequency of intercourse, fecundity of the users, how the method is used, and the quality of the product. But more than for other birth-control methods, the effectiveness of barrier methods depends on how well couples use them.^14,15 A method that is rated as less effective could actually be more effective for a particular couple if they use it correctly and regularly. Most contraceptive failures can be ascribed simply to inadequate compliance with the prescribed regimen. Barrier contraceptives and condoms used correctly at every sexual intercourse can be very effective in preventing pregnancy. In fact, consistent use of condoms with a spermicide may offer contraceptive protection that rivals that of the birth-control pill. Acceptance of all barrier contraceptive methods except the condom fell since the introduction of oral contraceptives and intrauterine devices (IUDs).^6,7

The reported range of failure or pregnancy rates is vast, from fewer than one to more than 30 per 100 woman-years, depending on the study, the method, and the population.^13,16 The best results are shown in clinical studies using exacting clients' selection with considerable input of resources to diminish follow-up losses, reinforce instructions, counter weak motivation, and increase compliance by encouraging correct and consistent use, thus increasing the reliability of the data. Couples available for the follow-up required for clinical studies of methods that basically are nonclinical generally are not representative of those most likely to benefit from them. Thus, the results of most clinical studies tend to be better than the actual performance of any given method during general population use, when a method is more subject to human frailty and inconsistent behavior. Clinical studies of contraceptives are subject to investigator and client biases, and for all practical purposes, the statistically irreproachable study design of use effectiveness is an illusion. Measured thus imperfectly, the generally credited clinical effectiveness of various contraceptive methods is shown in Table 2. The physician prescribing a contraceptive should take into consideration the client's lifestyle and ethical values and should be nonjudgmental and unbiased in discussing the benefits and disadvantages of the methods available. Occasionally, physicians are criticized for their involvement in providing contraceptive advice, education, and prescription; however, more criticism is deserved for physicians who ignore an opportunity when contraceptive advice was pertinent, needed, and even requested. Although in his or her medical role, the physician can and should act as an educator and advisor, he or she cannot be the judge of the client's sexual behavior and preferences. Too often, it is forgotten than when a physician is asked for contraceptive advice, the decision for sexual intimacy is already in the past.

Table 2. Pregnancy Rates for Birth Control Methods (1 Year of Use)

Barrier methods' effectiveness as contraceptives and in STD and HIV prevention is enhanced by their consistent and correct use. Frequently, these methods are overlooked and not prescribed; more often, people may fail to use them, change to other methods, or abandon their use and switch to no contraception, resulting in more user failures.² Conversely, a desire for the privacy offered by some barrier methods made them more acceptable, especially to women who are not willing to admit their sexual activity or will not consult a physician and be examined without having a health problem. For many potential users, the imminence of coitus and the fear of pregnancy are the only stimuli sufficiently powerful to arouse interest in contraception. Most barrier contraceptives are available over-the-counter without a prescription, do not necessitate a physical examination, and, for some people, in certain particular circumstances, may be the best or only effective method available. The correct and consistent use of barrier and spermicidal methods of contraception is determined by the complex interaction of the inherent attributes of the method, user characteristics, and situation. Method attributes include the extent of interference with sexual spontaneity and enjoyment, the amount of partner's cooperation required, and the ability of the method to protect against unwanted pregnancy, STDs, and HIV. User characteristics include motivation to avoid unintended pregnancy, fear of contracting an STD, ability to plan, cultural and religious attitudes regarding sexuality and contraception to which she is subjected, comfort with sexuality, and previous contraceptive experience. Characteristics of the relationship, stage of reproductive career, and previous sexual experiences are important situational influences.^8–10

It is reported that barrier and spermicide methods provide approximately 50% protection against STDs and pelvic inflammatory disease.^17,18,19 Their use has been associated with lower rates of cervical cancer than other methods of contraception.^{20,21,22,23,24} Women who never use barrier methods have twice the chance of having cancer of the cervix develop.²⁵ Barrier methods also contribute to the prevention of infertility.^{18,19,26,27,28,29,30} A problem sometimes associated with the use of vaginal contraceptives is toxic shock syndrome (TSS), a rare and sometimes fatal systemic infection with Staphylococcus aureus. TSS is the only life-threatening side effect associated with the diaphragm, cervical cap, and contraceptive sponge. However, its actual occurrence is rare; since 1979, only 55 cases have been reported to the Centers for Disease Control and Prevention (CDC). The CDC estimated that approximately one case of TSS occurs per 75,000 sponge users. In the United States, 95% of TSS cases occur among women. Of 40 cases of TSS in which a menstrual history was obtained, 95% were temporally associated with it.^31,32

Every contraceptive method in use today has drawbacks, and collectively they leave major gaps in the ability of people to control fertility safely, effectively, and in culturally acceptable ways throughout their reproductive life. Patients are more likely to remember what is stressed repeatedly as important by the health provider; however, knowledge does not necessarily result in action, and compliance decreases with time. Most women perceive pregnancy as a greater hazard than acquiring an STD. Although a woman's fertile period is limited, no woman knows when ovulation occurs, so women should be advised to use contraception at all times. A woman is fertile only a few days every menstrual cycle. The chance of pregnancy of any one act of sexual intercourse has been estimated to be approximately 2% to 4%.³³

The main considerations against the acceptability of barrier contraceptives are the necessity for touching the genitalia, messiness, storage, resupply, disposal, and direct relation to coitus. Some methods are bulky and difficult to store, carry, and use discreetly. In addition, planning is required, as well as a certain degree of compulsiveness on the part of the person or couple to ensure consistent use. All these predicaments occur to some extent with most users in most cultures.⁸

All contraceptive methods are complementary, not competitive. Each method offers a different balance of advantages and disadvantages, and the physician should be ready to advise or prescribe another method when the patient is not satisfied with the current one. The prescription or fitting of a contraceptive device should always be accompanied by thorough instructions for its proper use. Never assume the patient understands the correct use of the method chosen, and consider that the printed material for most contraceptives is usually above the level of literacy of the intended audience. Functional health literacy influences contraceptive understanding, attitudes, and behavior. Women with more education are better able to control their own sexuality. More education is associated with better health outcomes, a lower number of pregnancies, and lower infant and maternal morbidity and mortality, as well as higher life expectancy.

Reproductive health involves not only the prevention of unwanted conceptions but also of STDs and HIV. To increase the degree of prevention, particularly of STD infection, it is reasonable in certain circumstances to consider recommending the use of two contraceptive methods concomitantly (e.g., systemic hormonal contraceptives or IUDs and condoms, or sterilization and condoms).^34,35,36 On first analysis, this may look absurd, but none of the most effective contraceptive methods prevent STD transmission. Regarding dual contraceptive use, Cates³ commented, “the more effective the primary contraceptive method [used by the woman] was in preventing pregnancy, the lower the level of consistent use of the male condom.” It has been speculated that offering the women the added advantage of disease prevention increases the acceptability of condoms and their consistency of use. Patients usually attach different priorities to preventing pregnancy or STDs, and these priorities may change over time and among relationships.^{3,34,35,36,37,38,39,40,41,42}

Barrier contraceptives are indicated for: (1) women susceptible of getting pregnant to whom hormonal contraceptives and IUDs are contraindicated; (2) women who do not want to use anything hormonal or “chemical” that may have a systemic effect or “something” that must be carried in the body; (3) as an interim method until systemic contraception can be started or an IUD inserted; (4) during lactation and the puerperium, while they are still bleeding (if acceptable, the condom should not be overlooked); and (5) women with a history of uterine bleeding due to blood dyscrasias, although condom use may be extended for these situations; (6) at the end of reproductive life (perimenopause), when fecundity is low, the frequency of intercourse is decreased, and sex relations are sporadic; and (7) for women who, while using more reliable contraceptives like the pill, injections, or IUDs, express serious preoccupation about STDs and future fertility (dual method).

The condom (also known as a prophylactic, rubber, sheath, or French letter) is the only male method of contraception available besides coitus interruptus (withdrawal) and male sterilization. Its invention is attributed to Gabriel Fallopio (1564).⁴¹ It is one of the oldest and most extensively used contraceptives. The worldwide upsurge of STDs as well as the unstoppable pandemic of HIV/AIDS contributed to dilute most of the reservations about condoms and its use held by society at large. Because of its excellent record of infection prevention and contraceptive protection, its availability, and simplicity of use, the condom has become the darling of family planning clinics. It offers protection against unintended pregnancy and serves as the greatest defense against acquiring an STD or HIV infection; its historical role in the prevention of STDs is unmatched by any other method of contraception. Protection, however, is not 100% in either case. There is consistent clinical evidence from prospective studies of discordant couples, in which one partner is infected with HIV and the other not, that latex condoms used correctly during every act of sexual intercourse are very effective, not only in preventing unintended pregnancy but also HIV transmission STDs.^42,43,44,45 When used correctly during each sexual act, condoms are very effective in preventing unintended pregnancies and STDs. In this dual capacity, condoms may be regarded as the contraceptive gold standard against which all other contraceptive methods should be gauged. In strict comparison, most other contraceptive methods fall short, in fact, considering the specifications for an ideal contraceptive: high effectiveness, safe, reversible, inexpensive, free from side effects, light and inconspicuous, aesthetically acceptable, self-administered, simple to use, requiring no special skills or professional intervention, easy to store and distribute, offering effective prevention against STD infection, long shelf life, and use independent of sex. Male condoms answer with ease all those requirements except the last.⁴⁶ Condoms also have an important role to play in the rare cases when women are hypersensitive (atopic allergy) to contact with semen.

Condoms are widely available, easily obtainable, and reasonably inexpensive (even provided without charge by many family planning and STD clinics and some student health services). They do not require prescription or fitting. They have virtually no contraindications or side effects, except occasional allergy to the latex rubber^47,48 or the powder or lubricant by either partner. Problems possibly related to being powdered with talc have been reported.^49,50 Latex allergy is estimated to be 1% to 3% in the general population and 6% to 7% in persons frequently exposed to latex (health workers).⁷ Condoms are inconspicuous. They are simple to use, and their use is easy to teach and understand, even by people with limited or no education. To a certain degree, condoms constrict the penis and may attenuate somewhat glans sensitivity. This might inhibit erection in some users; however, in others, it may be a bonus that translates into prolonging coitus by delaying ejaculation. Condoms are an ideal method for sporadic or unanticipated coitus, for those who have sex infrequently, or for those who are faced with an unexpected sexual encounter. Condoms are a responsible alternative method for couples who wish to share the responsibility for contraception, as well as when immediate assurance of successful protection against conception is psychologically important to either partner. Condoms are recommended as an interim method before hormonal contraception may be started or an IUD inserted. Some women like the condom because they prefer the man to take the contraceptive responsibility and rely on his decision making or because they want to avoid contact with the ejaculate or postcoital messiness. Table 3 lists the indications and contraindications for condom use.

Table 3. Indications and Contraindications for Condom Use

  Indications

  Male

  Male contraceptive control preferred
  Genital or penile disease, cystitis, urethritis, including active sexually transmitted disease
  Sensitivity or allergic reaction to vaginal secretions
  Premature ejaculation

Condoms are made of latex rubber, polyurethane, and natural membranes (Lamb's cecal pouch). Most commercially available condoms are made of latex rubber. They come in an astounding variety of shapes (e.g., blunt or with a reservoir tip, ribbed, speckled, peppered with dots, contoured, with a helix or spiral rib, with a loose pouch over the glans or the penile shaft). Condoms come in a kaleidoscopic variety of colors, combinations, even fluorescent, and flavored, with up to 16 different tastes. They come in different sizes: standard (170 mm long and 50 mm wide); long, 30% larger; 45%, extra-large; 6%, narrower; 15%, shorter and 6%, narrower. They come as extra-strength and extra-thin. They may be lightly powdered or lubricated with silicone or a water-soluble spermicide or without spermicide, or a desensitizing product. Their variety seems to be limited only by the imagination of the manufacturers. Indications are that there is a market for such diversity and attesting to the contemporary losing of old social restrains about sexual intimacy. Usually, condoms are neatly rolled and packaged flat in paper, plastic, or aluminum foil. They have a long shelf-life, especially if they are protected from direct sunlight, heat, oily substances, and ozone, all of which contribute to rapid latex decay.⁵¹ Latex condoms lubricated with a spermicide and packaged in aluminum foil should be favored. However, there are no studies that show that condoms lubricated with a spermicide are more effective than those unlubricated. Condoms with spermicide decrease the risk of PID (pelvic inflammatory disease), infertility, and ectopic pregnancy. Lubrication may increase slippage.^52,53,54,55 Rear entrance that is lengthy and vigorous coitus increase ruptures. Approximately one condom break occurs per 100 acts of coitus; however, reported figures indicate a range between 0% and 12%, with most publications giving figures of 2% to 5%.^52,53,54,55 In a U.S. survey with a breakage rate of one to 12 per 100 episodes of vaginal intercourse, one pregnancy resulted from every three condom breakages.⁵⁶ During manufacture, condoms are individually tested electronically for holes and imperfections and must meet the stringent standards set by the American Society for Testing Materials and the U.S. Food and Drug Administration (FDA).⁵⁹ In the United States, condoms are imprinted with the date of manufacture or an expiration date. Aging seems to be the best predictor for condom breakage. However, just as important is how they are packaged and stored and how are they handled when used. Latex condoms form a continuous, impervious barrier to bacteria and viruses. In vitro laboratory tests have shown that latex condoms provide effective protection against gonorrhea, nongonococcal urethritis, Chlamydia trachomatis, cytomegalovirus, human papillomavirus, herpes simplex virus, HIV, and the much smaller hepatitis B virus.^6,7,57,58,59 One FDA study found that fluorescent polystyrene microspheres similar in diameter (110 nm) to the HIV virus (90 to 130 nm) could pass through 29 of unlubricated latex condoms (p< .03). The harsh physical conditions of the in vitro test under which the study was performed included 30 mL of a watery suspension of the particles at a concentration 100 times that reported for the average normal human ejaculate (3 mL) with a pressure of 90 mmHg over 30 minutes. The authors acknowledge the superior capacity of the latex condoms in containing HIV virus.^55a Seamen on leave in a port with a high prevalence of infected commercial sexual workers produced striking proof: none of 29 sailors who reported using condoms became infected, but 71 (14%) of 499 sailors who did not use condoms became infected with gonorrhea or nongonococcal urethritis.³ In a project that counseled HIV-discordant couples every 6 months, over 6 years there was no HIV seroconversion.⁵⁸ Women who are partners of condom users are less likely to become HIV positive.^60,61,62 One study followed 245 HIV-discordant couples for an average of 20 months. Among 124 who related using condoms at every coitus, no new cases of HIV were detected, even though approximately 15,000 sexual intercourses were reported. Among the 121 couples who used condoms irregularly, 12 new cases of HIV resulted, a 4.8 incidence rate per 100 person-years. Couples who used condoms more than half the time had approximately the same number of HIV seroconversions among the spouses previously HIV negative than among those who rarely used a condom.⁶³

Most users of condoms are more worried about avoiding unwanted conception than preventing an STD; however, this important personal and public health aspect of contraception never should be relegated to a secondary role. It is worthwhile to emphasize that the prevention of STDs may prevent future infertility^{17,18,26,27,28,29,30} and cancer of the cervix.^{20,21,22,23,24} Barriers to condom use among women ages 15 to 30 years attending four Planned Parenthood clinics were related to two restricting factors: pleasure and intimacy, and low perceived need.⁶⁴

Nonoxynol-9 (N-9), the spermicide used in most lubricated condoms, may cause the release of a natural rubber latex protein that may increase the chance of subjects having a hypersensitivity to latex develop. Natural rubber latex protein levels leached from latex condoms vary from brand to brand: condoms lubricated with N-9 have a fourfold to fivefold increase of natural rubber latex protein compared to the same brand without the spermicide.⁴⁷ For latex-sensitive persons, even condoms without N-9 may cause an allergic reaction.^47,48 Latex allergies and urinary tract infections (UTIs) associated with barrier contraceptive use are problems that only a few people experience.

Although N-9 may protect against HIV infection, it is unclear whether the genital irritation associated with latex allergy or N-9's local effect may increase the individual risk of infection. Such sensitivity may preclude correct use of condoms by susceptible persons; hence, they may be exposed to infection because of failure to use condoms rather than as a direct effect of using them. Condoms lubricated with N-9 have been associated with an increased frequency of vaginal and UTIs with Escherichia coli versus condoms without the spermicide.^68,69 UTIs increased with frequency of condom exposure from 0.1 (95% confidence interval, 0.65 to 1.28) for weekly or less during the previous month to 2.11 (95% confidence interval, 1.37 to 3.26) for more than once a week. Exposure to N-9-lubricated condoms produced a higher risk of UTI with odds ratios increasing from 1.09 (95% confidence interval, 0.58 to 2.05) for use weekly or less to 3.05 (95% confidence interval, 1.47 to 6.35) for more frequent use.⁵⁹

Data on pregnancy rates with condoms are limited. Reported condom failures range from 1.2% in the United Kingdom to 60% in the Philippines, with most studies between 4% and 14% in the first year.⁵⁹ In the various National Surveys of Family Growth, high-parity women aged 25 to 34 years who smoked and had used the method for less than 2 years had a pregnancy risk of 14.7.^13,70 The contraceptive effectiveness of the condom is acknowledged to be less than that of oral contraceptives, hormonal injections and implants, and the IUD; however, when condoms are used consistently and correctly, more so with an adjuvant (e.g., contraceptive cream, jelly, foam, or suppository) placed precoitally in the vagina, their use effectiveness is very high. They may even match the use effectiveness of the pill, which requires daily motivation, even when sexual activity is sporadic. Kestelman and Trussell^34,79 made a computer model of the use of condoms and spermicides simultaneously and arrived at a probability failure during perfect use of both of 0.05%, which is lower than that reported by perfect use of combined oral contraceptives. Latex condoms fail most frequently because they are not used than because of imperfections.

Skin condoms made from the cecum of some lambs are also available. They are preferred by some users, who claim higher sensitivity. Their thickness is similar to that of rubber latex condoms (approximately 0.07 to 0.08 mm). They are considerably more expensive and not as easy to find. No use-effectiveness data are available on natural membrane condoms. They represent less than 1% of the condoms sold. They must be kept moist to prevent cracking, so they come with an excess of lubricant. They are reliable for contraception and prevention of bacterial STDs, but their ability to impede the passage of all types of viral STDs has produced conflicting results in laboratory studies. They are considered acceptable for the prevention of bacterial diseases but not reliable for the prevention of most STDs of viral cause.

Nonlatex condoms have been developed to obviate the problem with latex allergy. Male synthetic condoms are manufactured using a dipped process similar to latex condoms or a cut-and-seal process using a synthetic elastomeric film. They are less elastic and wider than latex condoms, making them less constrictive. Avanti is the only commercially available synthetic male condom. It is made from Duron, a thermoplastic polyester polyurethane. Avanti looks like a straight-sided, reservoir-tipped condom. It is wider, approximately 65 mm when lying flat versus 52 mm for the standard latex condoms. Avanti had a larger breakage rate than latex condoms. Tactylon, another plastic condom made by the dipping process from another synthetic elastomer, has been cleared by the FDA, but it is not found commercially. Three Tactylon models were manufactured (standard, baggy, and with a wider closed end of 80 mm) to allow greater comfort by diminishing glans constriction and to provide a more elastic, standard shape condom. Tactylon also had a larger breakage rate than latex condoms. Ezon, a synthetic elastomeric condom, not cleared by the FDA, has a new design. Rather than being rolled on like latex condoms, Ezon is slipped onto the penis; it can also be donned from either end. Ortho McNeill Pharmaceutical of Canada and Carter-Wallace, Inc, are two other companies involved in the manufacture of synthetic elastomeric condoms. According most reports, they brake and slide more often than latex condoms.^{71,72,73,74,75,76,77,78,79}

It is unlikely that a physician will have to provide instructions on condom use, but in some situations, as when dealing with the sexually uninitiated, full discussion of this method, even its demonstration, may prevent anguish and needless hardship. Occasionally, it may be important to teach the social skills required to ensure condom use by a reluctant partner. Condom use can be shown using one of the available wooden or plastic models, a test tube of adequate size, or any other appropriate object. Never assume that because proper condom use seems so obvious, it will be used correctly. The following advice should be offered to the potential user. The condom should be applied over an erect penis before any contact with the partner's body or genitals takes place. If the man is uncircumcised, the foreskin should be pulled back before condom placement. A small length may be unrolled over one or two fingers and then placed on the penis. The rolling rim of the condom should be outside. Care should be taken that no air is trapped at the condom tip. The closed end of the condom should be pinched and held with the fingers of one hand; this space allows for penile thrusts and preserves glans sensitivity while allowing room for the ejaculate. The rest of the condom is rolled completely over the shaft of the erect penis. After ejaculation and before penile detumescence, the penis should be withdrawn from the vagina while holding the sheath with the fingers pressing against the base of the penis to keep it from slipping off and to avoid spilling semen into the vagina.

Buy condoms of good quality, packed in aluminum foil, preferably lubricated with spermicide (unless allergic to them). Use a new condom every time, and also if there is a suspicion that the condom may be damaged or has not been placed properly, even while using it. Do not unroll the condom or inflate it for testing, because very likely it will be ruined. All condoms are tested electronically during manufacturing. Throw away any condom that is or looks dry or brittle; one that seems to have been damaged by fingernails, rings, or so forth during placement; or one that was not placed correctly. After ejaculation, withdraw the penis before it becomes soft while holding the condom against the base of the penis; take special care to avoid spilling semen. If desired, after intercourse, inspect the condom for tears or holes by urinating into it before removal. Dispose of the condom in an appropriate, discreet manner.

The female condom, Reality, is an important new development in barrier contraceptives. It offers to the woman a very effective contraceptive as well as infection prevention under a woman's control. A soft polyurethane pouch to be used by women prevents contact with the penis and the ejaculate. The only female condom available commercially with the brand name Reality (Fig. 1) consists of a soft, medical-grade polyurethane sheath open at one end and closed at the other. It has two flexible rings of the same material, one at each end. The external open ring is designed to stay outside the vagina, resting against the vulva. The inner ring, at the closed end of the sheath, is firmer and must be inserted into the vagina. The device is supplied lubricated with a silicone-based lubricant without spermicide and an additional supply of lubricant. Insertion is facilitated by squeezing the inner ring with one hand while separating the vulvar labia with the other as when inserting a tampon or a diaphragm. Care should be taken not to twist the sheath; otherwise, penetration will be impossible. The internal ring should be pushed beyond the pubic bone and as close as possible to the cervix. The manufacturer recommends that the internal ring, which is not incorporated into the wall of the condom, should not be removed. The manufacturer also advises using the extra lubrication provided inside the sheath to facilitate penetration and that the device not adhere to the penis and ride in the vagina with coital movements, becoming a source of vaginal irritation and mucosal damage. After intercourse, the open ring should be squeezed and twisted to keep the semen inside without spilling. The device is to be used only once. Compared to other barrier methods, the female condom is expensive; however, some users indicate it may be washed and used again, although reuse should be discouraged. The female condom places the contraceptive method under the woman's control.⁸⁰ Like its male counterpart, it provides dual protection against unintended conception, STDs, and HIV. It also offers some perineal protection against skin infections and parasites. In addition, it has the advantage that it can be inserted well in advance of coitus.^81,82,83 Polyurethane is not allergenic, much stronger, and more resistant to heat than latex condoms; it is not sensitive to oily lubricants or storage under conditions that would damage rubber latex condoms.⁸¹ Care should be taken not to damage the membrane with fingernails or rings. Unlike the diaphragm and cervical cap, it requires no fitting.

The female condom is less effective than the male condom, diaphragm, sponge, and cervical cap (see Table 2).^{40,84,85,86,87} A study by Family Health International and the Contraceptive Research and Development Program (CONRAD) at three sites in Latin America and six in the United States gave a 6-month life-table pregnancy rate of 15.1 per 100 women (12.4 in the United States, 22.2 in Latin America). For perfect users, the pregnancy rate was 4.3 per 100 women, which is comparable to the male condom and the diaphragm. Acceptability of the device in general has been favorable by the women who selected it.^80,81 In a small study at Harlem Hospital in New York, two thirds of the women liked the female condom very much or somewhat. Half of them reported that their partners liked the device, 17% were neutral, and 25% disliked it. Seventy-three percent of respondents and 74% of their partners preferred the female condom over the male condom.^88,90 Although reuse should be discouraged, some users indicate it may be washed and used again. Reuse of the female condom is a common practice in developing countries. In a well-designed study, 50 women were provided with a female condom to be used at every intercourse; the condom was used for 295 coitus. The women reported using the same device for up to eight times, washed, dried, and relubricated it (with a vegetable oil or Vaseline) between uses. After completion of the study, five holes were detected on the Reality condoms; they were independent of the number of reuse cycles, for a breakage rate of 1.8%. The holes were at approximately 28 mm from the external ring. They were attributed as damaged by handling since they were located where twisting of the condom occurs before removing it is advised.^94,95 FDA test results of quality control (e.g., water leakage, air bursting, and tensile strength) were above the FDA minimum. In a U.S. study, the breakage rate was slightly higher (1.9%). In a 6-month prospective behavioral intervention study promoting barrier contraception for STD prevention, 1159 STD clinic patients were exposed to the female condom. They were provided with a 3-week supply of either male condoms or female condoms with male condoms as a backup. Of the 731 women who tried the female condom at least once, 232 (32%) used it 10 or more times. The proportion of women who reported using the female condom exclusively during the previous month remained relatively constant throughout the follow-up period, decreasing from 16% during the first month to 14% during the last month. Women who were employed or who had a regular partner at baseline were more likely to try it.

No one contraceptive method fits everyone's cultural habits, needs, desires, and lifestyles. The female condom, although not perfect aesthetically or functionally, is a welcome addition to the contraceptive armamentarium. It may have a restricted following; however, it has proved acceptable to women in quite different scenarios and provides its users with credible dual protection (contraception, STDs, and HIV) under a woman's control.

Invention of the contraceptive diaphragm is credited to Dr. Wilhem P.J. Mensinga of Felnsburg, Germany, who, using the pseudonym Dr. Karl Hasse, described it in 1881.¹² It was introduced in America in the early part of this century by the illustrious feminist Margaret Sanger, who brought the diaphragm from England and Holland on returning from her self-imposed exile. It was popularized by her followers and the family planning movement she initiated as part of her efforts to liberate women from the burdens of unwanted pregnancy. The vaginal diaphragm was the first highly effective method of contraception available to women; as such, and for more than 40 years until the advent of the birth-control pill and the IUD, it was the backbone of the family planning movement in the United States. It was also the first medically oriented method. The diaphragm was originally used by upper and upper-middle-class women who had not only the sophistication to recognize their sexual rights but also the means and privacy to take advantage of them. It placed the contraceptive initiative and responsibility in women's hands. Safe, without local or systemic side effects, inconspicuous in its use, low in cost because it is durable, effective when well fitted and used consistently, the diaphragm remains an important mechanical contraceptive method. Until the diaphragm became available, the only effective methods were withdrawal, the condom, improvised vaginal sponges, and abstinence.

The original Mensinga vaginal diaphragm consisted of a narrow, flat steel band, as in a watch spring, forming a ring. Vulcanized rubber completely covered the ring and closed the space, forming a dome. This domed rubber cup, with no modifications except for improvements in the quality of the rubber and the ring, has remained virtually unchanged as an excellent female-controlled mechanical contraceptive. Because of their construction with rubber or latex rubber, they are very sensitive to oily substances and lubricants. Properly fitted and placed diaphragms ride diagonally in the vagina between its posterior fornix and the tissues on the back of the pubic arch.

There are different types of diaphragms (Fig. 2 and Table 4). The flat spring or Mensinga diaphragm allows lateral compression but has no frontal elasticity. The coil spring type has a ring made of coiled steel that permits good lateral as well as limited frontal elasticity. Flat and coil spring diaphragms form a straight line when compressed to insert them. Because of their construction, they offer only lateral elasticity. They are suitable for most women, and they fit well, even when there is moderate vaginal relaxation without cystocele. Arcing spring diaphragms come in two types. The hinged or “bow-bend” diaphragm has in the core of its steel coil two semicircles of rigid steel that permit it to bending only in one position, forming a pointed arc. It is rigid in the anteroposterior axis and exerts strong lateral pressure. It cannot be fitted in most women with a retroverted uterus. The other arcing diaphragm is the All-Flex. The rim of this diaphragm forms an arch regardless of where it is compressed. It also offers some frontal elasticity. Most women find arcing diaphragms easier to insert because their curving assists in guiding it. They fit well, even in those vaginas with some relaxation or in the presence of a long cervix. The differences among them are only the type of ring and the degree of vaginal support they may offer and the ease of fitting and of insertion and removal by the user.

Table 4. Contraceptive Diaphragms Available in the United States

Each type of diaphragm has its own advantages; however, not all women can be fitted (Table 5). Satisfactory results may be obtained with any of the varieties available, provided a good fit can be attained and the woman is able and willing to use it consistently. The diaphragm is a contraceptive method free of systemic side effects; it may be used while nursing.

Table 5. Indications and Contraindications for the Contraceptive Vaginal Diaphragm

  Indications

  Female control desired
  Systemic hormonal contraceptives and IUD contraindicated or unacceptable

Spermicidal jellies or creams are used to provide lubrication to facilitate insertion of the diaphragm. The spermicide theoretically offers two added advantages: spermicidal activity and the added mechanical obstacle to sperm migration. The lubricant should not contain products that may damage the rubber or are irritating to the woman or her consort. Approximately 2 inches or a spoonful of the spermicidal jelly or cream is placed in the cup, and some of it is smeared on the rim and the other face of the device. Jellies provide more lubrication. A cream or foam can be indicated when less lubrication is desired; foams are less liked for this purpose. The adjuvant spermicidal jellies and creams are, to a large extent, bactericidal and may diminish the risk of acquiring some STDs.^7,96 They contribute to the effectiveness of the method.

The diaphragm and spermicidal agent may be inserted hours before intercourse, but if more than 2 hours elapse, additional spermicide should be placed in the upper vagina for maximal protection. Without any empiric data to support it, removal of the diaphragm is advised after 6 to 8 hours from ejaculation. Even with the extraordinary buffer capacity of the seminal plasma, sperm survive in the normal vagina less than 2 hours. Sperm survival should be shorter in the presence of a spermicide. The diaphragm should not be left in the vagina for more than 24 hours. When repeated coitus occurs, a fresh application of the spermicide should be inserted with an applicator or with a finger without removing the diaphragm. The diaphragm may be left in overnight and for a full day at a time. Its use during menstruation is not recommended, but if that is done, the diaphragm should not be placed too long before sexual relations, and it should be removed shortly afterward. The danger of TSS with prolonged retention of the device should be emphasized, because TSS has been described after diaphragm use.^97,98 Although TSS is rare, approximately 95% of cases reported have been temporally related to menstruation.^31,32,97,98 Douching is not recommended, but the woman may do so if she wishes. Prolonged retention and improper fitting can cause vaginal irritation, even mucosal damage.

For the sexually active woman, insertion of the diaphragm may become part of her daily routine before retiring, because many users prefer to have it in place well in advance of any possible coitus to avoid the need for extemporaneous preparation. Uninhibited couples may want to share in its insertion and include proper placement as part of lovemaking. Placement by the man can be an act of responsibility, love, and sexual provocation.

The major problem in prescribing a diaphragm is the absence of well-trained personnel. Fitting demands skill, patience for teaching, and time (usually 15 to 20 minutes). Because diaphragms are not as popular as they were before oral contraception and IUDs arrived, adequate supplies (all models and sizes) often are not available. Many women have been conditioned not to touch and even fewer to explore their genitals. In some instances, a woman's attitude toward the insertion of tampons may give a clue to her feelings about putting the device in the vagina and ensuring its proper position. Obese women, women with short fingers, and those with manual limitations may not be able to use this method.

The diaphragm, properly cared for, may last several years, making it a rather economic method. After use, the diaphragm should be washed, dried thoroughly, and placed in a container. If desired, it can be powdered with corn starch. However, talcum powder contributes to the rapid deterioration of the rubber. Periodically, the diaphragm should be inspected against a strong light for weak spots or perforations. After a delivery or a change in weight (10 lb or more), a recheck of the fitting is advised, but routine adherence to this policy has been questioned.⁹⁹

Diaphragm users experience fewer changes in cervical cytology and fewer cases of cervical dysplasia, carcinoma in situ, and cervical cancer.^{20,21,22,23,24,100} No relation was found between the use of the diaphragm and the occurrence of endometriosis.¹⁰¹ The diaphragm is a highly effective method of birth control when fitted properly and used consistently. The degree of effectiveness depends to a large extent on the adequacy of the fitting, the motivation of the user, and the degree of sophistication of the group to which she belongs. A failure rate of two to eight pregnancies per 100 woman-years has been reported (see Table 2). These may be considered optimal results. Life-table pregnancy rates for the diaphragm range from as low as two to as high as 23 per 100 woman-years but are generally 14 to 20 per 100 woman-years.^13,16,102 Vessey and coworkers¹⁰³ reported a pregnancy rate of 1.9 to 2.4 per 100 woman-years for established diaphragm users. The failure rate was lower in women older than 35 years than in those younger than 30 years of age. The most successful diaphragm users are older and married, have completed their families, have experience with the diaphragm or other barrier methods, are better educated, and have a higher socioeconomic status. However, successful use by very young females showed that the method is suitable for all age groups, provided adequate fitting, training, and support are available.^103a

There are conflicting reports as to whether the use of an adjuvant spermicidal product is necessary to the effectiveness of the method. A pregnancy rate of one per 100 woman-years with the continuous fit-free use of a 60-mm arcing diaphragm, removing it briefly every day for washing, was reported.¹⁰⁴ A retrospective analysis in Brazil of the same practice found that it had a lower failure rate than the one found in a group of women using the diaphragm with a spermicide before each act of intercourse.¹⁰⁵ It was speculated that the difference was due to the failure of noncontinuous diaphragm users to use the device on every sexual occasion because of the inconvenience of inserting it on demand. A recent prospective British study projected to study 200 volunteers using a fit-free 60-mm diaphragm for 1 year was halted after enrolling 110 women because of a high failure rate—24.1 per 100 woman-years (29.5 for the women without diaphragm experience and 17.9 for women with barrier contraceptive experience). Major reasons for discontinuation, apart from accidental pregnancy, were malodor and problems with removal and insertion.¹⁰⁶

Diaphragm and sponge use result in a decreased incidence in STDs compared with condoms and tubal sterilization.⁴² However, there are no prospective studies of diaphragm protective effect against HIV. Fihn, and, associates⁶⁸ reported an increased incidence of UTIs in diaphragm users. In a case-control study, they found a relative risk of 2.5 for UTI in diaphragm users compared with that of oral contraceptive users (26.6 versus 8.9 per 1000 patients-month, respectively). It was associated with vaginal colonization with E. coli.^6,7,101,102 Initially, it was thought that the problem was due to the rim of the diaphragm pressing against the urethra, causing irritation and some degree of urinary retention that was perceived as infectious in origin. Different studies have examined the problem and shown that a change in the vaginal flora occurs during barrier contraceptive use. The normal vaginal environment, rich in Lactobacillus acidophilus, has a quite acid pH (3.5 to 5.5), except during menstruation and vaginal bleeding and after semen deposition. Spermicides used with the diaphragm, as with other barrier methods, eliminate from the vagina the lactobacilli as well as most of its normal flora, which is replaced by a flora rich in anaerobes and E. coli. Studies also indicate that spermicide use can increase the risk of bacteriuria with E. coli because of an alteration of the vaginal flora.^{107,108,109,110} A comparison of sexual intercourse alone with sexual intercourse with a diaphragm and spermicide used in the preceding 3 days was strongly associated with increased rates of vaginal colonization with uropathogenic flora, including E. coli (p < .0001), other gram-negative uropathogens (p = .0045), group D streptococci (p= .0015), and also Candida (p = .0001). It was concluded that bacterial and fungal vaginal microflora are strongly influenced by the recent use of a diaphragm and spermicide and minimally affected by sexual intercourse alone.¹¹⁰ Diaphragms offer good protection against PID and infertility, not for cystitis, however.

Historically older than the vaginal diaphragm,¹² the contraceptive cervical cap has aroused limited interest among the medical profession in the United States. It is more popular in the United Kingdom, and in some middle European countries, it is more popular than the diaphragm. Conventional cervical caps can be worn for up to 48 hours. Permanency for more than 6 to 8 hours is frequently a cause of malodor. The ones that may be found in the United States are manufactured in England. They are made from rubber or latex rubber and come in three different types: the Prentif or cavity-rim cap, a rubber device resembling a bowler hat, with a thick rim; the Dumas or vault cap, a shallow domelike latex cap, thin in the center and with a thick rim without a metal ring; and the Vimule cap, also a domelike latex cap, thin at the center and thick at the periphery, with a slanted rim. All are intended to fit over the cervix; the Vimule and Dumas extend to the vaginal fornices (Fig. 3).

The Prentif cap, the only cervical cap approved by the FDA for prescription in the United States, comes in four sizes (internal rim diameter of 22, 25, 28, and 31 mm) to adapt to the individual anatomic conditions.^111,112 These caps require individual fitting. Because they are made of rubber, all are sensitive to oily and greasy substances. The Prentif cap should be filled approximately one-third full with a spermicidal cream before insertion.

Cervical caps differ from diaphragms because they are not placed to fit in the vagina but only to cover the uterine cervix, which is being recognized as possibly the principal site of HIV invasion.^113,114 Less elastic than the diaphragm, the Prentif cervical cap is held in place partly by suction on the cervix but mainly by the positive abdominal pressure and weight of the abdominal organs on the vagina. When fitted and placed properly, the cervical cap is somewhat more difficult to place properly and remove than a diaphragm, even when the cap is provided with a removal string.

Proper use of the cervical cap requires extensive handling of the genitalia, ability to locate the cervix, and to place the device on it. Cervical caps cannot be used in women with a very short cervix, poor vaginal support, a badly lacerated cervix, an inflamed or infected cervix, uterus, or adnexa, as well as those with a history of human papillomavirus or herpes simplex virus infection or cervical dysplasia. It is also contraindicated in women with short fingers, a lack of mechanical dexterity, or an aversion to touching their own genitals. Table 6 lists guidelines for the use of cervical caps, and Table 7 lists contraindications to their use.

Table 6. Guidelines for the Use of the Contraceptive Cervical Caps

  Place sufficient spermicidal gel onto the cap
  Insert the cap without rush ahead of a potential sexual engagement
  Make sure that the cap is engaged on the cervix
  After intercourse, do not remove the cap before 2 hours
  After intercourse, the cap may remain up to 2 days
  Repeated intercourses do not require additional spermicide
  Recheck the position of the cap before repeating intercourse
  Do not use the cap during menstruation
  Douching before of after removing the cap is not necessary

Table 7. Contraindications for the Use of Contraceptive Cervical Caps

  Temporary

  Menstruation, active vaginal, cervical, or other genital infections until treated
  Puerperium
  Suspected pregnancy

Frequent complaints are recurrent dislodgment during coitus found at the time of removal, malodor, and discoloration of the cap. Although the diaphragm should be removed 6 to 8 hours after intercourse, the cervical cap may be kept in place up to 5 days.¹¹⁵ The recommendation should be not to leave the cap in place for longer than 24 hours. The spermicidal activity of jellies is exhausted in such time; creams, however, have been found to retain activity up to 7 days from insertion.¹¹⁶ This, however, should be discouraged. As the length of permanency increases, some drawbacks tend to occur: malodor, vaginal or cervical irritation, and even damage to the vaginal mucosa^{111,115,117,118}; also, it may increase the chance of women having TSS develop. Concerns about epithelial changes due to the cervical cap's staying in place for an extended time against the cervix were addressed by Gollub and Sivin,¹¹⁹ who did not find changes in Papanicolaou (Pap) cytology after 1 year of use of the Prentif cervical cap. However, Bernstein and coworkers¹²⁰ reported a 4% change from Pap class I to class II after 3 months of use of the Prentif cap versus 1.7% among diaphragm users. Cervical caps should not be worn longer than 2 days and never during menstruation. In the United States, based on the cytologic changes observed in a few users, new cervical cap users are recommended to have a Pap test on accepting the cap and again 3 months after starting the method, then yearly. The National Institutes of Health (NIH) diaphragm clinical trial 120 found no significant differences in the results of smears between cap and diaphragm users every 3 months during the first year. Cervical caps are not as effective as are the condom and vaginal diaphragm (see Table 2). Reported pregnancy rates vary from 8.1 per 100 woman-years during the first year to 19.1 per 100 woman-years for the same period.^{8,102,111,112,117} As with the diaphragm cap, refitting is required after a delivery. There are no data on the effectiveness of the cap on prevention of HIV infection. The use of spermicides with N-9 increases the frequency vaginal colonization with E. coli and Enteroccocus.

The FemCap (FemCap Inc, Del Mar, CA) is a new type of cervical cap.^123,124 This ingenious device, made of very elastic silicone rubber (Fig. 4), is aptly described as shaped like a sailor hat. It consists of a thin dome to fit and cover the cervix completely, reaching the vaginal fornices. A pliant circular flange, called the brim, encircles the dome and slightly flares outward to conform to the vaginal vault, obliterating the vaginal fornices. The brim is narrower anteriorly and wider posteriorly to adapt to the shallower anterior fornix and anatomy of the vagina. The border of the dome at its junction with the brim forms a slightly narrower and thicker soft, rounded ring to seal the device to the cervix. The one-piece device is provided with a strap of the same material, located over the dome, to facilitate removal. Three sizes are available: the smallest (24-mm internal dome diameter) for nulliparous women, medium (28 mm) for women who never have a delivery while pregnant, and 32 mm for parous women. On the basis of a 6-month comparative study of the FemCap and a conventional diaphragm, Mauck and coworkers calculated the annual probability of unintended pregnancy for the FemCap as 22.8% and 13.7% for the diaphragm, respectively.^125,126 Based on the woman's pregnancy history, FemCap could be self-fitted on 84% of the women. There were more instances of difficult fitting as well as of insertion and removal of the device for the FemCap than for the diaphragm; however, it is reported that insertion is easier than for the Prentif cap. Adverse experiences were similar with both devices, fewer than 6%. FemCap was considered safe and was associated with significantly fewer urinary tract infections. The estimated 1-year pregnancy rate, based on the 6-month pregnancy rate, was calculated of approximately 23%, ranging from 15% for nulliparous women and 30% for parous women. The spermicide should be placed in the space between the outer aspect of the dome and the brim, and a smaller amount should be smeared on the edge of the dome and its interior. The instructions provided indicate that it requires a smaller amount of spermicide than the Prentif cervical cap. It is theorized that as ejaculation occurs, the brim, in close apposition to the vaginal wall, will direct the ejaculate and motile sperm toward the space surrounding the dome where most of the spermicide is located.¹²² Because the greater volume of spermicide is not in direct contact with the vaginal epithelium, it is assumed that there will be less local irritation. The device does not require additional doses of spermicide before repeated intercourse.

Silicone rubber is nonallergenic, and the cap may be washed with any soap or detergent, boiled, or even sterilized. It should be good for 2 years and should not change color, lose elasticity, or become malodorous. In the initial study, some women wore the device from 3 to 7 days without irritation or damage to the cervix or the vaginal vault; 5% reported vaginal odor, itching, and UTI.¹²⁴ The study population was very satisfied with the device.¹²⁵

A new type of contraceptive cap is Lea's shield (YAMA, Inc, Millburn, NJ), developed by Dr. Schlome Gabbay (Fig. 5). This intriguing device, made of silicone rubber and designed to be sold over-the-counter, is unique because one size should fit all women. It consists of a thick bowl-shaped dome with an internal diameter of 30 mm to fit and cover the cervix. The dome's rim is thicker in the part that should fit the posterior vaginal fornix and on the opposite side has a strong, thick loop of the same material to facilitate removal. The loop, placed against the anterior vaginal wall, contributes to its fixation and is accessible to the fitting and removal finger. The dome has a hole at its top that connects with an ample and supple flat tubular valve that runs parallel to the dome and the loop. This permits the escape of air trapped at insertion and the passage of cervical secretions, thus creating better fit over the cervix.

According to the instructions provided, Lea's shield should be used with a spermicidal gel. Approximately one third of the dome should be covered with the gel, which should also be applied to the thick edge of the dome to facilitate insertion and to the external aspect of the valve.^126,127,128

A preliminary evaluation by postcoital tests was satisfactory.¹²⁹ A clinical study by CONRAD (Contraceptive Research and Development) found a 12month pregnancy rate of 15%.¹³⁰ Acceptability of the device was very high, with 87% indicating they would recommend the device. The device has received wide distribution in Canada and Germany.¹³¹ Another new vaginal barrier made of silicone is a device developed by PATH (Program for Appropriate Technology in Health) called SILCS (pronounced silk); it also comes in a single size.¹³²

A disposable silicone cervical cap, Oves Cap, is available to be sold over-the-counter in France. It can be left in place for up to 3 days.

Pharmaceutical constructs are to be inserted directly in the vagina minutes before sexual intercourse. All available contraceptive inserts in the United States contain N-9 as spermicidal. These preparations are the suppositories: Encare, containing a 2,27% of N-9, Koromex Inserts with 125 mg of N-9, and Semicid with 100 mg of N-9. Also available is the vaginal contraceptive film (VCF) C-Film with 70 mg of N-9. Data on use effectiveness are scarce (see Table 2). Not available in the United States but widely available abroad is the Japanese vaginal foaming (effervescent) tablet NeoSampoon. This tablet contains menfegol as spermicidal.

Probably the oldest mechanical intravaginal device used for contraception is the vaginal sponge and its variations. Wads of cloth, cotton tufts, sea sponges, powder puffs, and the like have been used throughout history and are still in use all over the world, either alone or in combination with different solutions, presumably spermicidal. The sponge combines mechanical and spermicidal barriers to sperm. The vaginal sponge provides some advantages over the diaphragm and the cervical cap, although not as much contraceptive protection. It is self-administered and does not require a pelvic examination or fitting; one size fits all. It has no contraindications, except for persons allergic to the sponge material or the spermicide with which it may be impregnated or persons averse to touching their genitals. Available without prescription, the vaginal sponge can be personally procured, inserted, and removed—even self-made. It can be used as a back-up method for the condom. There is no waiting period after insertion to be effective. It can be inserted hours before a sexual encounter, avoiding a potentially messy interruption of sexual foreplay, while upholding confidentiality and providing undiminished protection. The user may engage in repeated coitus without the need for additional preparation.¹³³ Sponges may offer protection against some STDs but not against gonorrhea, syphilis, and HIV.

The disposable Today sponge, the only commercially available sponge in the United States, was withdrawn from the market because it could not comply with requirements of the FDA and remain commercially viable; recently, it has been reintroduced and become available again. It consists of a molded hydrophilic polyurethane soft sponge impregnated with 1 g N-9. It had to be moistened before insertion. A ribbon loop was provided to facilitate removal. In multicenter clinical studies, its use effectiveness was lower than that of the diaphragm.^102,128 Women with vaginal sponge experience had a failure rate of 13.2% by the life-table method. Women without vaginal sponge experience had a 16.1% failure rate; for diaphragm users, it was 5.9% and 12.0%, respectively.^134,135 A study in Bangkok among commercial sex workers found that sponge users were less likely to become infected with chlamydia, gonorrhea, and candida infections.¹³⁶ Borko and Behlilovic¹³⁷ reported a failure rate of 5.6 per 100 woman-years. Reasons for discontinuation were accidental pregnancy, local irritation, discomfort, malodor, and vaginal infections. The perceived advantage reported was that it was self-administered, under a woman's control, and did not interfere with sexual pleasure.

A study of commercial sex workers in Nairobi found that the sponge with 1 g N-9 did not offer protection against HIV infection.¹³⁸ The sponge contributed to vaginal dryness, and the seroconversion was credited to an increase in vaginal sores that facilitated viral infection. Women in this study had multiple coital episodes with the sponge; the situation may be quite different in other clinical scenarios. Frequent use of N-9 has been linked to vaginal irritation and mucosal abrasions, which were dose-dependent.¹³⁹ There have been cases of TSS temporally associated with use of the contraceptive sponge. The risk was mostly related to its use during menstruation and the puerperium and prolonged retention of the device.^31,140

In the United Kingdom and Canada, there are two contraceptive sponges: Protectaid and Pharmatex. Another sponge, Avert, with 100 mg N-9 is in preliminary studies. Protectaid is a polyurethane sponge impregnated with a spermicidal and viricidal gel, F-5, a mixture of 25 mg each of benzalkonium chloride, sodium cholate, and N-9.^141,142 The Pharmatex sponge contains 60 mg of benzalkonium chloride. The Protectaid and Avert sponges have the advantage of being wet. There is no need to wet them before use. Sponges are an appealing and effective option under a woman's control that do not require professional intervention. Self-administered methods for use that are controlled by women are acquiring new relevance because of the interest of some potential groups of users that encourage self-reliance in health and reproductive matters, as well as in international program strategies, where it is impossible to provide all the population that may be interested in reversible contraception with professionally delivered methods.

Substances for vaginal application formulated to prevent conception have been in use since pharaonic times and form part of the folklore of most cultures. From the time of their discovery, spermatozoa were found to be killed by many substances. Van Leeuwenhoeck¹⁴³ observed that rain water rendered dog spermatozoa motionless. Almost 2 centuries later, Kolliker¹⁴⁴ did the first systematic study of compounds with antisperm activity and reported that organic and inorganic salts were toxic to spermatozoa. Until the late 1950s, different vaginal creams, pastes, suppositories, and other vaginal inserts were of uncertain quality, suspect origin, and questionable effectiveness. Margaret Sanger and her followers and scientific advisers took the lead until the FDA became involved and started to establish requirements for their safety and effectiveness.

The need for substances for vaginal use that prevent the spread of STDs has remained an incomplete agenda. Increasing knowledge of the ecology of the human vagina, and the different susceptibility of its flora to existing spermicides, is providing basic knowledge related to the problems encountered in the general use of existing spermicides. Considerable research effort is being made by the private and public sector with the goal of finding products with strong bactericidal and viricidal activity, in addition to spermicidal activity, that will not affect the vaginal and cervical epithelia and will preserve vaginal mucosa integrity. More than 50 products are at different stages of testing. The pharmaceutical industry has remained uninterested in this quest since the market for preparations of this kind will be mostly for populations with meager acquisitive power.

Most spermicides fall into the following categories with considerable overlap: electrolytes, sulfhydryl-binding substances, bactericides, surfactant agents, and enzyme inhibitors.¹⁴⁵ Collectively, they are classified as microbicides. The most widely used spermicides commercially available use surfactant agents such as N-9, octoxynol-9, and menfegol, which disrupt cell membranes and kill bacteria, parasites, and most viruses.^5,5a Other common compounds have shown spermicidal activity (e.g., benzalkonium chloride, chlorhexidine, gramicidin, cholate, Betadine). Laboratory studies indicate that in vitro N-9 inactivates many sexually transmitted pathogens, including Neisseria gonorrhoeae, C. trachomatis, herpes simplex viruses, Treponema pallidum, Candida albicans, Trichomonas vaginalis, and HIV.^5,5a,7a,40 Doubt remains, however, about the ability of N-9 to destroy human papillomavirus^146,147; this is attributed to the fact that the virus is nonenveloped.¹⁴⁶ N-9 also has a deleterious effect on the integrity of the cells of the vaginal and cervical epithelium that is dose-related.¹³⁹ The resulting disruption of the normal epithelium makes it more susceptible to invasion by HIV and other viruses.^{137,148,149,150} The antibacterial activity of N-9 against the normal vaginal flora, eliminating, among other regular dwellers, the peroxidase-producing L acidophilus, facilitates its colonization by uropathogenic bacteria.^{69,107,108,109,110} Women who use spermicides regularly have increased colonization of the vagina with E. coli and may be predisposed to more frequent bacteriuria and recurrent cystitis.^{68,69,107,108}

Hydrogen peroxide-producing strains of lactobacilli, responsible for the acid vaginal pH, are susceptible to N-9. Spermicides may provide a selective advantage in colonizing the vagina with N-9-resistant uropathogens such as E. coli, possibly by a reduction in hydrogen peroxide-producing lactobacilli.^149,150 Hydrogen peroxide combines with peroxidase contributed by eosinophils and chloride to produce a viricidal environment.^151,152 This is a fascinating field of current investigation, a way to deliver safely H₂O₂ with spermicides to control the vaginal invasion by uropathogenic organisms. Of anecdotal interest is that before the advent of sulfanilamides and antibiotics, some gynecologists, confronted with undiagnosed vaginitis with the resources available at the time, used to sponge the vagina with peroxide. Recently, a similar treatment was proposed: a 30-mL instillation of hydrogen peroxide 3% while keeping the speculum in place and draining the vagina after 3 minutes.¹⁵³

An ample gamut of pharmaceutical methods have been and are still used to deliver spermicides into the vagina. There are traditional forms, such as vaginal jellies and creams, suppositories, and effervescent tablets, with many improvements extant. There are newer forms, such as foams and, more recently, the vaginal contraceptive film that complete the list (Table 8).

Table 8. Commercial Spermicides Available in the United States

  Gels, Jellies, and Creams

  Advantage 24 Gel
  Conceptrol Gel
  Gynol II Original Formula

  Jelly

Spermicides require a number of immediate precoital maneuvers and handling of the genitals; this is not acceptable to some potential users. All conspire for misuse and frequent discontinuation. All have a number of disadvantages that limit their acceptability. When used alone, they offer limited contraceptive protection. The reported range of failure or pregnancy is vast (see Table 2), from fewer than one to more than 30 per 100 woman-years.^13,15,16 Table 9 lists the indications and contraindications for topical spermicides.

Table 9. Indications and Contraindications for Topical Spermicides

  Indications

  Adjuvant to mechanical contraceptives: diaphragm, cervical cap, condoms
  Adjuvant to rhythm, natural, or periodic abstinence method
  Temporary, during the first cycle on progestogen-only minipills
  Temporary or transient method before sexual relations are initiated or before a systemic contraceptive can be started or an IUD inserted
  Increase in vaginal lubrication desired
  At the end of reproductive life when sexual relations are sporadic, fecundity is low, or the woman is unwillingor unable to use other method

The practical value of vaginal spermicides is that all are widely available. They are sold without prescription, which makes them accessible to a large population unwilling to seek professional advice and examination. They are simple to use, relatively inexpensive, and are under a woman's control. Although their effectiveness against STDs and HIV is being questioned, vaginal spermicides may offer some protection against some STDs.^40,41,96

In general, spermicidal products are bulky and conspicuous. The recommended dose varies according to the physical characteristics of the product. Film, suppositories, and foaming tablets are dispensed in units for direct use. Foams, jellies, and creams are provided with a syringe inserter that contains the recommended amount. Most users' complaints are excessive lubrication, leakage and messiness after sex, local irritation and pruritus, and occasional allergy to the active ingredient or the vehicle. Jellies provide greater lubrication than creams but in general are aesthetically less acceptable because of excess leakage after coitus. Creams and foams are slightly “dryer” and less messy. The dosage of jellies and creams is approximately 5 mL, which is the capacity of the plastic applicator syringe with which these products are usually marketed. It is believed that the bulk of the vehicle in jellies and creams may contribute as a partial mechanical barrier. Foams consist of a fluid base in which the spermicide is dissolved; they are packed in a pressurized container with a gas as propellant. The material is released as a foam. They adhere and distribute better in the vagina. Because the water in creams and jellies is substituted in foams by the propellant gas, foams tend to be less messy, have less leakage, and aesthetically are more acceptable. Foam containers should be thoroughly shaken before the foam is released into the syringe applicator. Foam applicators deliver 7 to 10 mL.

Most spermicides have an excellent shelf-life when stored properly at room temperature. They should not be refrigerated and never frozen. Vaginal spermicides are recommended as an occasional or provisional method while the woman is waiting for menstruation before insertion of an IUD or waiting to start hormonal contraception, during the initial cycle on a progestogen-only minipill, or for the unexpected sexual encounter.

Spermicides are used mostly in combination with mechanical methods (e.g., condoms, diaphragms, and cervical caps), as lubricants, adjuvants in case of condom rupture, and secondary protection against STDs and HIV. The CDC stresses that spermicides are no protection against STDs and HIV. To prevent the transmission of HIV and other STDs in high-risk populations, the CDC recommends the consistent and correct use of male latex condoms with spermicide. Women wanting to use spermicides alone should be made aware that accidental conceptions are more the rule than the exception.

Former studies of N-9 showed a potential reduction of STD infections but were inconclusive in regard to its ability to prevent HIV infection. An extensive, well-designed recent study of the National Institute of Allergy and Infectious Diseases and Family Health International¹⁵⁴ in Cameroon to a great extent settled the issue of how much protection can be obtained by the use of a spermicide with N-9. The N-9 vaginal contraceptive film did not confer any additional protection to women from HIV, gonorrhea, or chlamydia infection beyond that provided by condoms. The study enlisted 1292 HIV-seronegative, nonpregnant commercial sex workers who were not allergic to N-9 or to latex. They were randomly assigned into two groups. One group was given condoms and the contraceptive film with 70 mg N-9. The second group was given condoms and films containing no spermicide (placebo). The women and the investigators were masked to the product being used. There were 478 women in the N-9 film group and 463 in the placebo group who completed 1 year of follow-up. The results were strikingly similar in size as well as in the number of sexual encounters that occurred in the year (147,996 and 146,942, respectively). Of 100 women using N-9 film and condoms for 1 year, 6.7 became infected with HIV, 33.3 with gonorrhea, and 20.6 with chlamydia. Infectious rates for the placebo film and condoms were 6.6 for HIV, 31.1 for gonorrhea, and 22.2 for chlamydia per 100 woman-years. The overall rate of HIV transmission (6.7 per 100 woman-years) was half the transmission rate previously estimated in this population. Women in the N-9 film group (42.2%) had genital sores; those in the placebo group had 33.5 genital sores.¹²⁹ The N-9 spermicidal film did not confer additional protection from HIV, gonorrhea, or chlamydia infection beyond that provided by condoms. The N-9 vaginal contraceptive film did not protect from HIV and other infections. This excellent study shatters the hope that spermicides could offer reliable protection against STDs and HIV. However, the film is a small, tenuous dispenser of a very limited amount (70 mg) of N-9. There may be other methods that could be more efficient in delivering larger quantities of the same spermicide or other more effective compounds.

The indiscriminate use of the vagina as a place to attack unwanted sperm must be viewed with caution. Studies of the vaginal sponge among commercial sexual workers showed that the rate of HIV infection was higher among them because of the local irritation attributed to the N-9. However, this situation is certainly very different from that of most users of spermicides, in which a single dose of the spermicide is applied less frequently.

Risks of miscarriage associated with spermicide use, whether before conception or at the time of conception, are inconsistent across studies.^{155,156,157,158} Two prospective studies evaluated spermicide use both before and at the time of conception and found no association with spontaneous abortion.^144,156 A case-control study of spontaneous abortions of conceptions during spermicide use also showed no association.¹⁶⁰ One study reported a loose association of spontaneous abortion with the use of spermicides,¹⁶¹ but after subsequent analysis, the association was considered spurious.¹⁶² The New York City miscarriage study did not support the premise that spermicides carry a risk of causing spontaneous abortion if they were used either before or around the time of conception.¹⁶³ Associations of tetrapod abortuses¹⁶⁴ and Down's syndrome^165,166 with spermicides were reported, but such associations were denied by other studies.^158,166,167 Two studies of births provide information on spermicide use previous to conception,^{166,167,173,174} and neither detected a malformation. Considering the numerous analyses, a truly elevated risk for birth defects seems highly improbable.^168,169,172 The New York City investigators also performed a study of spermicides and trisomies that could test possible effects under various conditions.^179,175 Data were collected on prenatal karyotypes at 17 medical centers in the United States and Canada. Spermicide use was compared among trisomies and among chromosomally normal karyotypes at the same time of gestation. The spermicidal data were collected before the prenatal diagnoses were made to avoid potential recall bias. Trisomy could not be linked to spermicidal use in the cycle of conception. The study was sufficiently large to exclude risk ratios of two or more with confidence. The null result held for trisomies 13, 18, and 21, combined or separately, for the nearly two thirds of all cases with trisomy 21.¹⁷⁰ The American College of Obstetrics and Gynecology also issued a technical bulletin denying any association between spermicidal use at the time of conception and congenital malformation.¹⁷¹

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