CONTRACEPTION

NEW FEMALE INTRAVAGINAL BARRIER CONTRACEPTIVE DEVICE Preliminary Clinical Trial Alfred A. Shihata, M.D. The Scripps Institutions of Medicine and Science San Diego, California James Trussell, Ph.D. Office of Population Research Princeton University Princeton, New Jersey

ABSTRACT The Fern Cap, a silicone rubber cervical cap, is shaped like a sailor’s hat. While its dome covers the cervix, its rim fits snugly into the vaginal fornices, and its brim adheres and conforms to the vaginal walls. A spermicidal material is applied to the cap, then it is positioned over the cervix by hand or with a special applicator. The device is removed by hand up to 48 hours after insertion, but no sooner than eight hours after intercourse. Women chosen for the trial had contraindications to or were dissatisfied with the currently available contraceptive methods. Each woman was fitted with a cap of suitable size and instructed in its use. She was then asked to note any side effects and the dates of her menses in a diary. One-hundred-twenty-one women were enrolled in the study. Five became pregnant. Of those, two reported dislodgment of the cap during intercourse; the other three admitted to non-use of the cap on several occasions. This device has proven so far to be safe, effective and acceptable to women and men. It has several advantages over the currently available barrier contraceptive devices. The silicone rubber material from which it is made is nonallergenic, durable and easy to clean. Its design fits the anatomy and accommodates physiological changes. The Fern Cap is easy to insert and remove; an applicator facilitates insertion for some women. Instruction for use of the device requires short time from the health care provider. Submitted for publication April 22, 1991 Accepted for publication May 13, 1991

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CONTRACEPTION

INTRODUCTION Of all the temporary contraceptive methods available, none is acceptable to all women, or completely safe and effective.1 There is a compelling need for intravaginal barrier contraceptive devices which can substantially decrease the risk of sexually-transmitted diseases (STDs). Intravaginal barrier methods currently available have been in use without improvement for more than a century.* Despite continuous improvement of the birth control pill, it continues to produce some side effects. The use of the intrauterine device (IUD) has dramatically decreased, and its indication has been greatly restricted. The condom, although very safe and effective against STDs and AIDS, is not as acceptable to some groups as other forms of contraception. This paper presents a preliminary clinical trial on a new intravaginal barrier contraceptive device. The Fern Cap (Fig. 1) offers one more choice in the contraceptive field and one more tool in the fight against STDs. (A) Side View. Longer brim fits over posterior vaginal wall. (B) Vaginal Opening View. Seen between the brim and the dome is the groove which acts as a reservoir for spermicide and a trap for sperm. (C) Cervical View. Shows the opening which fits over the cervix and the rim, which fits snugly into fornices.

Figure 1: Fern Cap Intravaginal Device. 12

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SUBJECTS

AND

METHODS

Women 18 to 40 years old, whose use of currently available contraceptives is impeded by contraindication, dissatisfaction or the inability to tolerate side effects were chosen for this clinical trial. Women having any of the following conditions were excluded: pregnancy (or desire to become pregnant in the near future); Pap smear of Class III or higher; undiagnosed vaginal bleeding; pelvic pain; condyloma; or untreated STDs. Four women were unable to fit the cap correctly and were not enrolled in this study. Ninety-two percent of the participants were Caucasians, 6% were Black, and 2% were Hispanic. Each participant in the trial was informed of the experimental nature of the Fern Cap and signed an informed consent. Each was fitted with the suitable size, taught to use it, and asked to keep a diary, noting any side effects and the dates of her menses. A physical, pelvic exam, Pap smear, pregnancy test and STD screening were performed on each woman during the initial visit. Before leaving the investigator’s office, each woman was required to place and remove the Fern Cap correctly. If she was unable to place the device properly after a reasonable trial, she was instructed in the use of a special applicator (Fig. 2).

L) The

4pplicator

:B) Fern Zap mounted >n applicator.

Fern pon Jlicator in released ;itton.

JLY

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CONTRACEPTION Women were instructed to wash their genitals, rectal areas, and their hands before insertion of the Fern Cap, and to remove it no sooner than eight hours after intercourse. In order to avoid the remote possibility of Toxic Shock Syndrome, women were instructed not to keep the device in place longer than 48 hours and never to use the cap during menstruation. Women were instructed to continue to use their birth control pills in conjunction with the Fern Cap if they had no contraindictions to the B.C.P. A week after the initial visit, on a day following intercourse, each participant in the study returned to the investigator’s office with her Fern Cap in place for the physician to check. The Fern Cap was removed, and a thorough examination was made of the portio vaginalis, and the adjacent vaginal walls. The cervical mucus was examined for sperm. Women were instructed to discontinue the use of the B.C.P. if they felt confident in the use of the Fern Cap and no sperm were found in their cervical mucus. In this limited study, no sperm was found in the cervical mucus of any participants. A follow-up Pap smear was performed on each participant three months later, and yearly thereafter. All women who inadvertently wore the Cap longer than the recommended time (48 hours) were requested to report to the clinic for a thorough pelvic exam. None of the fourteen women who wore the Cap three to seven days had any visible trauma in the entire circumference of the portio vaginalis or the vaginal walls? The physician continued to see each participant at three-month intervals to investigate any side effects and review her diary (Table I).

Table I: Study Protocol

This diary included: compliance (i.e., consistent and proper use with each act of intercourse); dates of menstrual periods; dates and times of device insertions and removals; discomfort to either partner; dislodgement during intercourse or any activity; and any odor, irritation, abnormal vaginal bleeding, discharge, symptoms of urinary tract infection or any abnormal event.

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CONTRACEPTION The Fern Cap used in this study came in three sizes - 24, 28, and 32 millimeters (internal diameter) - which could fit almost all women. The smallest was used exclusively for nulliparous women, the largest for multiparous women, and the medium one for those who could not be fitted correctly with either the large or small cap. Material supplied to each woman included the Fern Cap, spermicidal jelly (Ortho Gynol II contraceptive jelly)’ containing 3.0% nonoxynol-9, a diary, written instructions, and an instructional video tape demonstrating proper use and care of the Fern Cap. Women of limited dexterity were also given the applicator to facilitate insertion of the cap. RESULTS Data

Collection

and

Analysis

The following data from both the patients’ diaries and clinical examination were recorded and analyzed to evaluate the safety, effectiveness and acceptability of the Fern Cap: age; level of education; compliance with study protocol and instruction for proper use; pregnancy; infection; post-coital presence or absence of sperm; any evidence of trauma to cervix, vagina or penis; bleeding; Pap smear conversions; discomfort of partner or patient before, during, or after intercourse; ease of insertion and removal; displacement/expulsion during use (how frequently); odor from device or vagina; and discontinuation of the device for any reason. From February 1988 to December 1990, 121 women enrolled in this clinical trial. Not one woman was lost to follow-up. However, fifteen of these women failed to appear for their first follow-up appointment at one week. All of these were contacted by telephone, and all stated that they had not used the device and had decided not to participate in the trial. The remaining 106 women contributed a toal of 1300 cycles of exposure. The average, minimum, and maximum contributions were 12.3 cycles, 2 cycles, and 26 cycles, respectively; 56 women (53%) contributed at least 13 cycles. During the trial, 5 of the 106 women became pregnant - two reported dislodgment of the device during intercourse, the other three admitted non-use of the cap on several occasions. Hence, the Pearl index failure rate is 5 per 100 women-years of exposure. The life-table probability of failing within one year (13 cycles) is 4.8% (with a standard error of 2.1 percentage points). This preliminary study reveals, therefore, that the contraceptive efficacy of the Fern Cap is quite high. The side effects reported were minor, and some of them For example, 20 percent of the women decreased over time. complained of difficulty in removing the Fern Cap. By the end of three months, only two percent reported such difficulty. *Ortho Pharmaceutical

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Corp., Raritan, N.J. 08869

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CONTRACEPTION

Figure

3:

Fen I Cap in place shows the cervix completely covered and the rim fitting snugly into the fornices.

Figure

4:

Close -up of Fern Cap. The brim can be seen tightly sealed again: : the vaginal wall. 16

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CONTRACEPTION Table

II: Comparison Between the Fern Cap and Cervical Cap Currently in Use Fern Cap

Safety

?atient

Instruction

Ease of Insertion and Removal

Odor

Design

Dislodgement

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Cervical Currently

Cap Used

Made of silicone rubber, non-reactive, non-allergenic, durable, tolerates heat well, and can be sterilized.

Made of natural rubber (latex), allergenic, porous, flimsy, disintegrates with heat or petroleum products.

Soft and atraumatic, covers cervix, fits snugly into the fornices, and adheres and conforms to the vaginal walls.

Very firm rim, with cavity disposed into it; may cause abrasion to cervix, vagina, and/or trauma to the penis.

15-20 minutes

1 to 2 hours

Easy; applicator facilitates insertion needed

if

Relatively difficult to insert and remove; may be impossible for some women.

5%

10% - 55%5

Anatomical; shaped like a sailor’s hat, has longer posterior brim and has a groove between the dome and brim that traps sperm and acts as a reservoir for spermicide.

Cup- or thimbleshaped, with disregard to the anatomy of the cervix, which is shorter anteriorly and longer posteriorly, and does not accommodate the angle of the cervix.

8%

lo%-27%6

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CONTRACEPTION Six women reported dislodgment of the Fern Cap during intercourse, but they did not get pregnant. Nine women reported irritation from nonoxynol-9, which was then replaced by octoxynol3.0% (Koromex contraceptive cream),+ thus relieving four of them. Five reported urinary tract infection and vaginal odor. Two participants converted their Pap smears from Class I to Class II; both had condyloma. Four converted from Class II to Class I. None of the participants had Class III Pap smears. During the study, three women developed chlamydia, seven had yeast infections, and one trichomonas. None of the women or their sexual partners reported any discomfort, and neither the examining physician nor any participant reported any trauma to the cervix, vagina, or penis. DISCUSSION Currently, barrier contraceptives offer the best defense against the spread of sexually-transmitted diseases by shielding the fallopian tubes, the endometrium, and the cervix from potential invasion.4 While barrier devices are the safest of all temporary contraceptive methods, they suffer from poor effectiveness and acceptability. Therefore, there is an urgent and compelling need to provide safer, more effective and acceptable barrier methods. The Fern Cap covers the cervix completely, its rim fits snugly into the fornices (Fig. 3), and its brim adheres and conforms to the vaginal walls (Fig. 4), thereby increasing its effectiveness over the currently available mechanical barrier contraceptive devices (see Table II). The ease of insertion and removal, and the lack of trauma or discomfort to either sexual partner make the Fern Cap more acceptable to women and men. It is cost-effective in terms of time and money, as health-care providers will need only a short time to instruct women in its use, and the Fern Cap is reusable for two to three years. Submission to Federal Food and Drug Administration is pending collection of more extensive efficacy data. +Schmid Laboratories,

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Inc., Little Falls, N.J. 07424

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CONTRACEPTION ACKNOWLEDGEMENTS I am deeply indebted to Professor G. Bernstein, Ph.D., M.D., Obstetrics and Gynecology, University of Southern California School of Medicine, for his valuable advice and guidance throughout the study and for designing the study protocol. I am equally indebted to Assistant Professor Anita L. Nelson, M.D., Obstetrics and Gynecology, University of California, Los Angeles School of Medicine, for her extremely constructive critique,which markedly improved and clarified the video-tape for instruction in use of the Fern Cap.

REFERENCES 1.

Hatcher RA, Stewart F, Trussell J, et al. Contraceptive technology. 15th Rev. ed. New York: Irvington Publishers, 2; 130-52.

1990-

2

Bernstein GS, Conventional methods of contraception: condom, diaphragm, and vaginal foam. Clin Obstet Gyne 1974; 17: 2133.

3.

Bernstein GS, KiLzer LH, Coulson AH, et al. Studies of cervical caps: I. Vaginal lesions associated with use of the Vimule cap. Contraception 1982; 26: 443-56.

4.

Connell EB. Barrier Contraceptives. 37786.

5.

Koch JP. The Prentif contraceptive cervical cap: acceptability aspects and their implications for future cap design. Contraception 1982; 25: 161-73.

6.

Richwald GA, Greenland S, Gerber M, et. al. Effectiveness of the cavity-rim cervical cap: results of a large clinical study. Obstet Gyne 1989; 74: 143-48.

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Clin Obstet Gyne, 1989; 32:

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New female intravaginal barrier contraceptive device. Preliminary clinical trial.

The Fem Cap, a silicone rubber cervical cap, is shaped like a sailor's hat. While its dome covers the cervix, its rim fits snugly into the vaginal for...
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