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Contraceptive Technology Reports
Evaluation of a Female-Controlled Intravaginal Barrier Device: The FemCap
Authors: Linda Rogers, CRNP, Research Program Coordinator, Johns Hopkins Bayview Medical Center, Torri L. Ross, MPH, Senior Research Program Coordinator, Johns Hopkins Bayview Medical Center, and P.D. Blumenthal, MD, MPH, Associate Professor, Johns Hopkins University, Director, Contraceptive Research and Programs, Johns Hopkins Bayview Medical Center.
Peer Reviewer: Mitchell D. Creinin, MD, Associate Professor, Director of Family Planning and Family Planning Research, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine.
Over the last two decades, there has been a renewed interest in barrier methods due to their ability to protect against pregnancy and the transmission of HIV.1 This is exemplified by the increase in the use of male condoms since the early 1980s when HIV first appeared in the United States.2 Because the use of barrier methods other than male condoms has decreased, contraceptive research has focused on finding an acceptable female-controlled method serving the dual function of protecting against pregnancy and HIV. It is recognized that barrier methods are needed; particularly ones that offer HIV protection, and that are more convenient than those currently available. The condom needs to be used at the time of coitus and interferes with spontaneity. The diaphragm can be left in place for 24 hours, but a longer time frame may be more desirable for some women. Methods also are needed that are easier to insert and remove and that can be prescription-free.
Devices similar to the current cervical cap and diaphragm approved by the Food and Drug Administration (FDA) were designed and introduced in the United States in the late 1910s.3,4 Since this time, these devices have evolved to address such issues as odor, dislodgment, difficulty, and time required to fit the device, insertion and removal, and discomfort to male and female partners, all of which have affected acceptability. Even with these improvements, these devices remain poorly utilized.
Several barrier methods developed over the last 10 years have attempted to address the problems with the currently available methods. In 1994, the female condom was introduced to the public. Unfortunately, after FDA approval, the female condom was found by many users to be undesirable because of slippage problems, difficulty of insertion, discomfort with use, appearance, and expense.3 A newer barrier device, Lea’s Shield, approved by the FDA in March 2002, was designed to fill the niche for women seeking an acceptable barrier method. It is a diaphragm-like device made of medical-grade silicone with a valve to allow for the escape of air and mucus and a loop to simplify insertion and removal. The latest barrier method on the market, approved in March 2003, is the FemCap; this method also was designed to address the inadequacies of the devices on the market when it was conceptualized.
Design/Mechanism of Action
The FemCap is a silicone device shaped like a U.S. Navy "sailor’s" cap. The dome of the device fits over the cervix, the rim fits into the vaginal fornices, and the brim fits against the adjacent vaginal walls. One-half teaspoon of spermicidal gel is applied to the inside (the cervical side) of the cup and the brim, and one-half teaspoon is applied in the groove between the cup and the brim on the outside (the vaginal side). The device provides a physical barrier for the cervix from sperm and pathogens, and the spermicide provides a chemical barrier. There are three sizes of FemCap, which are determined by the diameter of the inner rim of the device. The smallest, the 22 mm, is designed for women who have never been pregnant. The medium (26 mm) is for women who have been pregnant but have not had a vaginal delivery, and the large (30 mm) is for women who have had a full term vaginal delivery. Parity alone has been found to be predictive for the appropriate size 85% of the time.5
The FemCap device was designed to combine some of the advantages of the diaphragm and the cervical cap. Like a diaphragm, it is relatively easy to insert. It is made of medical-grade silicone, which is stiffer than the latex in a diaphragm, but is not as rigid as the latex in a Prentif cervical cap. The silicone is less allergenic than latex and less likely to be harmed by petroleum-based lubricants and cleaning procedures. The device was designed to require less clinician time for fitting than the diaphragm or the cervical cap and comes in only three sizes, as opposed to the multitude of sizes for the diaphragm and four for the Prentif cervical cap. The cap fits less snugly over the cervix than a cervical cap and does not actively adhere to the cervix. The package labeling for the Prentif cervical cap requires that a pap smear be repeated after three months of use because an early trial found an increase in conversions from Class I to Class III (normal to dysplasia)6 goes here pap smears at three months.7 However, a subsequent re-analysis of that data found no statistically significant increase in abnormal pap smears at three months or at one year.8
The FemCap device that was approved by the FDA is a second-generation version of the original device that was used in the large U.S. randomized clinical trial. According to the manufacturer, several design changes were made to the device such as a strap that functions to facilitate removal by forcing the woman to push on the dome with her finger in order to slide her finger between the strap and the dome. This breaks the suction in the dome and also eases removal. Some other changes were made in an effort to improve the efficacy of the device. The "brim" portion that rests on the vaginal walls was lengthened to improve the barrier effect. With the first generation of the FemCap, a large proportion of the pregnancies in the trial occurred in parous women (i.e., those using the largest size cap). This cap was found to be slightly asymmetrical, and it was postulated that the movement of the cervix during coitus with the asymmetric device could have broken the contact of the brim and the vaginal wall (personal communication with Alfred Shihata, MD). The current large size FemCap has a slightly smaller dome than the original, a larger brim, and is perfectly symmetrical.
Fitting and Use
When providing a FemCap device, the fit should be checked by a clinician to ensure that it covers the entire cervix, extends into the vaginal fornices, and that the brim adheres to the vaginal wall. The device should not be easily dislodged, and the device should be comfortable for the woman. The FemCap is presently available only with a prescription and can be ordered directly through the company’s web site (www.femcap.com) and sent to the patient’s clinician. Fitting devices for providers and an instructional video also are available through the web site.
The FemCap can be left in place for up to 48 hours. Intercourse can take place as often as desired for up to 42 hours without the insertion of additional spermicide, because the device must be left in place for at least six hours after the last intercourse. In clinical trials, subjects were instructed not to use the device during their menses because of the theoretical risk of toxic shock syndrome, although the risk is not expected to be any higher than with the diaphragm. The odds ratio for toxic shock syndrome with a diaphragm is 11.7 compared to nonbarrier users.9 To remove the device, the woman should push her finger into the dome of the device to break the suction and to allow room to grab on to the strap. She then can slowly pull the device out of her vagina by holding onto the strap. The FemCap should be washed with antibacterial hand soap, dried thoroughly, and stored in its plastic case. 10
Efficacy and Acceptability
The randomized clinical trial on which FDA approval was based, compared the original FemCap and the Ortho All-Flex diaphragm. The treated population included 355 subjects who were randomized to the first generation design of the FemCap and 403 randomized to the diaphragm. Fifteen percent of the intent-to-treat population for the FemCap was excluded because of inability to insert or remove the device at enrollment, compared with 5% of the diaphragm group. Discontinuation rates for nonpregnancy reasons were not statistically different between the groups. Among women with previous diaphragm experience, those randomized to the FemCap were 2.5 times more likely to discontinue the study early. However, almost three-quarters of the FemCap subjects who had used both devices preferred the FemCap.5
The probability of pregnancy, using the six-month Kaplan-Meier cumulative unadjusted typical-use probability, was 13.5% for the FemCap users and 7.9% for the diaphragm users. The relative risk of pregnancy was 1.96 for the FemCap users compared with the diaphragm users, with the upper 95% confidence limit of 3.01. In order to demonstrate clinical equivalence, the study would have needed to demonstrate that the upper 95% confidence limit for the risk of pregnancy in the FemCap users was < 1.73. Therefore, clinical equivalence was not demonstrated. The six-cycle perfect-use pregnancy probabilities (11.2% vs. 7.4%) also did not demonstrate clinical equivalence.5 When the pregnancy rates were broken down by previous parity, the probability of pregnancy for nulliparous women was 9.5% for the FemCap (the small or the medium device primarily) and 9.1% for the diaphragm. However, for parous women, the pregnancy rates were 15.8% (primarily the large size device) and 6.9%, respectively.5 It should be noted that the potential design problems with the first generation device have been addressed, and there currently are no data regarding pregnancy rates with the new design.
There are differences in the recommendations for use of the FDA-approved FemCap compared to the way the original device was used in the clinical trial, which may have a large effect on efficacy. The large randomized clinical trial was paid for by funds from the United States Agency for International Development, because officials of that agency are very interested in finding effective barrier methods for use by women in developing countries. For this reason, they did not want a videotape to be used to train women in the clinical trial to use the device as this technology often is not available in developing countries. However, the FDA has approved a videotape to be included with packaging which details instruction on use, insertion, and removal. Additionally, the manufacturer recommends that a backup method be used for the first few weeks while the woman is learning to use the device. This was not allowed in the clinical trial.
Side Effects and Safety
Cervical cytology was one of the outcome variables in the comparative study between the FemCap and the diaphragm. Women were excluded from the study at initiation if they had any abnormalities on their pap smears other than atypical cells of uncertain significance (ASCUS), inflammation, or infection. At the end of the six-month trial, 7.0% of the FemCap and 8.4% of the diaphragm users had ASCUS pap smears. Of the FemCap and diaphragm users respectively, 1.3% and 1.4% had low-grade squamous intraepithelial lesions (SIL), and 0.7% of FemCap users and 0.6% of diaphragm users had atypical glandular cells of uncertain significance (AGUS). None of these differences were statistically significant.
Coital logs were kept by all study subjects during the comparative trial. There were significantly more problems reported by the FemCap users compared to the diaphragm users. Of the FemCap users, 30.6% reported that the device moved or dislodged, as opposed to 6% of the diaphragm users. However, there was no statistically significant association between dislodgment of the FemCap and pregnancy. FemCap users (11.6%) had more difficulty removing the device than diaphragm users (3.8%). Problems that were not statistically significant, but were reported by slightly more FemCap users, were "difficulty inserting" (10.3% vs. 6.5%) and "partner could feel device" (7.1% vs. 2.5%). Slightly more diaphragm users reported coital pain (2.8%) than FemCap users (0.6%). All of the coitally related problems with the devices were reported in less than 2% of coital acts for both groups.5
Adverse events of the urogenital system were not statistically different between the FemCap group and the diaphragm group with two exceptions. More FemCap users reported blood found in the device (9% vs. 4%), and fewer FemCap users developed urinary tract infections (UTIs) (7.5% vs. 12.4%).5 The increased risk of UTIs with diaphragm use has been consistent across multiple studies.11,12 This increase may be due to the design of the diaphragm or because of the spermicide used with it. The FemCap does not impinge on the urethra because the size of the brim is much smaller than the diaphragm, and much less spermicide is used with the device.
Role of Method in the Contraceptive Marketplace
The FemCap use requires planning and the ability to understand complex instruction. This method would be fitting for women who do not want or cannot use hormonal contraceptives or for women who have contraindications to intrauterine devices (IUDs). Additionally, because the device is latex-free, the FemCap is an appropriate method for women and their partners who have latex allergies. Women who have done well with the diaphragm, but have had problems with UTIs, might be an especially suitable group for this method. Barrier methods such as FemCap might offer protection against HIV transmission if data emerging about the role of the cervix in acquisition of HIV are borne out, and if protection against HIV is demonstrated in clinical trials. If this were proven to be the case, this would contribute greatly to its marketability; however, more information is needed from studies before this can be concluded.
As with all contraceptive methods, there are women for whom this method is not appropriate. Consideration should be given before prescribing the device to women uncomfortable with genital manipulation or inserting and removing foreign bodies from their vaginas. These women are more likely to have higher failure rates with the FemCap. In addition, women whose sexual habits are unpredictable and spontaneous should be discouraged from using this method as it does require motivation and planning.
Benefits and Limitations of Method
The cost of the FemCap, at $49.95, is an important advantage of this method.9 The device should last for two years, so the monthly cost is about $2 per month.1 Based purely on commodity involved, the device is less expensive than hormonal contraceptives on a monthly basis. However, one must take into account the cost of an undesired pregnancy with the method’s high rate of failure. Although some planning is required with the use of the FemCap, women can insert the device well before intercourse so as not to disrupt spontaneity when with their partner.
Not every woman can use the FemCap because one of the three sizes available may not fit correctly. Women with a cervix that is flush with the vagina after a cervical conization or with extremely large or a previously lacerated cervix may not be able to be fit with this device. The 13.5% six-month failure rate in the large clinical trial is higher than other barrier methods. More studies are needed to determine if the new design truly results in a lower pregnancy rate. As with all contraceptive methods, women should be fully counseled about the advantages and disadvantages before selecting the FemCap as their contraceptive method. (See Table, below.)
|Table: Benefits and Limitations of FemCap|
Although hormonal contraception and IUDs are highly effective, they are clearly not appropriate for all patients. The currently available female-controlled barrier methods are underutilized. The FemCap may be challenging for some women to use; for others, it may meet their needs in ways that enhance compliance and thus result in better efficacy than might have been achieved by a less acceptable method. This possibility alone can make this new, reasonably effective method a welcome addition to the contraceptive marketplace.
1. Moench TR, Chipato T, Padian N. Preventing disease by protecting the cervix: The unexplored promise of internal vaginal barrier devices. AIDS 2001; 15:1,595-1,602.
2. Piccinino LJ, Mosher WD. Trends in contraceptive use in the United States: 1982-1995. Family Planning Perspectives 1998, 30:4-10, 46.
3. Schwartz JL, Gabelnick HL. Current contraceptive research. Perspectives on Sexual and Reproductive Health 2002; 34:310-316.
4. Koch JP. The Pentif contraceptive cervical cap: Acceptability aspects and their implications for future cap design. Contraception 1982; 25:161-173.
5. Mauck C, Callahan M, Weiner D, et al. A comparative study of the safety and efficacy of FemCap, a new vaginal barrier contraceptive, and the Ortho All-Flex Diaphragm. Contraception 1999; 60:71-80.
6. DiSai PJ, Creasman WT. Clinical Gynecologic Oncology. St. Louis: The C.V. Mosby Co., 1981; 3.
7. Package Insert: Prentif Cavity Rim Cervical Cap. Lamberts Ltd. of London.
8. Gollub EL, Sivin I. The Prentif cervical cap and Pap smear results: a critical appraisal. Contraception 1989 Sep; 40:343-349.
9. Scwartz B, Gaventa S, Broome CV, et al. Nonmenstrual toxic shock syndrome associated with barrier contraceptives: report of a case-control study. Rev Infect Dis 1989; 11 Suppl 1:S43-8.
10. Web: www.femcap.com.
11. Hooton TM, Scholes D, Hughes JP, et al. A prospective study of risk factors for symptomatic urinary tract infection in young women. NEJM 1996; 335:468-474.
12. Hooton TM, Fihn SD, Johnson C, et al. Association between bacterial vaginosis and acute cystitis in women using diaphragms. Arch Intern Med 1989; 149:1,932-1,936.
After reading this article, the reader will be able to:
1. The purported benefits of the FemCap include:
A. No need to use microbiocide or spermicide.
B. It is recommended for use during menses.
C. It can be used for as long as 48 hours.
D. It has efficacy similar to a condom.
2. Possible limitations of FemCap include:
A. Risk of urinary tract infection is higher than with the diaphragm.
B. Risk of dislodgment is higher than with the diaphragm.
C. The FemCap can be left in place for only 24 hours.
D. Possible allergic reactions to the material used in the FemCap.
3. In respect to fitting the FemCap:
A. One size fits all.
B. It is similar to a diaphragm.
C. Size is dependent on patient’s weight.
D. Size is dependent on parity: one size for nulliparous, one size for parous, and one size for patients who have had an abortion or C-section.