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Pericoital (on demand) contraception: Diaphragm, cervical cap, spermicides, and sponge

Pericoital (on demand) contraception: Diaphragm, cervical cap, spermicides, and sponge
Literature review current through: May 2024.
This topic last updated: Oct 17, 2023.

INTRODUCTION — Pericoital contraception refers to nonhormonal reversible contraceptive methods that are used at the time of intercourse (ie, on demand) to prevent pregnancy. These methods prevent functioning sperm from entering the female reproductive tract. Female-controlled pericoital contraceptive methods include the diaphragm, cervical cap, spermicides, sponge, and the internal (formerly female) condom. The external (formerly male) condom is the main male-controlled pericoital contraceptive.

This topic will review the diaphragm, cervical cap, spermicides, and sponge. Information on internal (formerly female) condoms, external (formerly male) condoms, and contraceptive counseling and method selection is presented separately.

(See "Internal (formerly female) condoms".)

(See "External (formerly male) condoms".)

(See "Contraception: Counseling and selection".)

In this topic, when discussing study results, we will use the terms "woman/en" or "patient(s)" as they are used in the studies presented. Additionally, the term "female" is used on occasion to refer to contraceptive methods that were originally designed for individuals born with a vagina. We encourage the reader to consider the specific counseling and treatment needs of transgender and gender diverse individuals.

MECHANISM OF ACTION AND NOMENCLATURE — Although commonly thought of as barrier methods, the diaphragm, cervical cap, and the contraceptive sponge largely function by maintaining a reservoir of contraceptive gel against the cervix. Spermicidal foams, gels, creams, films, or suppositories provide contraception by immobilizing sperm, thus creating a chemical "barrier" against normal assent of sperm into the upper genital tract. As the diaphragm, cervical cap, sponge, and spermicide are only used at the time of intercourse, we will refer to these methods as "pericoital contraceptives" throughout. (See 'Vaginal spermicide and pH regulator gel' below.)

True barrier contraceptives are the internal (formerly female) and external (formerly male) condoms. They provide a physical barrier to migration of sperm from the vagina to the upper reproductive tract, where fertilization occurs.

(See "Internal (formerly female) condoms".)

(See "External (formerly male) condoms".)

CHOOSING A PERICOITAL CONTRACEPTIVE METHOD

Pericoital versus other contraceptive methods — In choosing a method of contraception, the advantages and disadvantages of the method need to be assessed and compared with advantages and disadvantages of alternative methods. For the primary indication of pregnancy prevention, pericoital contraceptives are considered less effective below long-acting reversible (LARC) and short-acting reversible hormonal (SARC) contraceptive methods (figure 1). Selection of a contraceptive method balances many patient preferences and is reviewed in detail separately. (See "Contraception: Counseling and selection".)

Advantages of pericoital contraceptives include [1]:

Is used only when needed.

The method is controlled by the person who could potentially become pregnant (ie, contraceptive agency) [2].

Very safe, with minimal complications.

No hormonal exposure or side effects, thus it can be used by patients with contraindications to hormone-containing products.

May be reusable (diaphragm should be replaced every two years, and one cervical cap can be used up to one year).

Relatively inexpensive and several are available over-the-counter.

Diaphragms and cervical caps cost approximately USD $80 for each device.

Nonoxynol-9-containing spermicide costs approximately USD $20 for a tube adequate for 10 or more applications. The vaginal pH regulator spermicide (Phexxi) costs USD $270 for a box of 12 prefilled applicators but may be available at a much lower price with insurance coverage.

The contraceptive sponge costs USD $10 to $15 for a package of three sponges.

Immediately effective and immediately reversible.

Can be used in combination with some other birth control methods, including external (formerly male) condoms and hormonal methods, to improve contraceptive efficacy and/or to prevent acquisition of sexually transmitted infections (STIs).

Pericoital methods that cover the cervix (eg, the diaphragm) may protect against assent of inflammatory pathogens, such as gonorrhea or Chlamydia, into the cervix or the upper genital tract [3], and methods that affect the vaginal pH (eg, vaginal pH regulator spermicide) may prevent some vulvovaginal infections and have some antiviral activity [4].

Disadvantages of pericoital contraception include [1]:

Failure rate is substantially higher than with hormonal methods, intrauterine devices, subdermal implants, or sterilization (figure 1).

In addition, higher than expected rates of contraceptive failure are reported for multiparous patients who use the cervical cap and contraceptive sponge (failure rates up to 20 to 30 percent). While a causal relationship between multiparity and higher pericoital contraception failure is not clear, there is biological plausibility in that the larger multiparous cervix may be more difficult to protect against assent of sperm with the cervical cap and sponge. Contraceptive decision-making should take this decreased efficacy into account.

The diaphragm, cervical cap, contraceptive sponge, and nonoxynol-9-containing spermicides do not protect against STI acquisition, including herpes simplex virus or HIV, because they do not separate penile skin and secretions from the vaginal epithelium the way that external and internal condoms do. However, for those methods that may interfere with assent of pathogens up the genital track (eg, diaphragm), clinical disease may be lessened if STI occurs. (See "External (formerly male) condoms", section on 'Protection from STIs' and "Internal (formerly female) condoms", section on 'Sexually transmitted infections'.)

Requires motivation at every act of intercourse and some skill to use.

The pericoital method and the necessary concomitant spermicide must be inserted before intercourse is initiated, which may be inconvenient or may reduce spontaneity.

Device methods that are spermicide-dependent must be kept in place in the vagina for six hours after intercourse.

Pericoital methods do not have the noncontraceptive benefits of hormonal contraceptives (eg, reduction in menstrual bleeding and dysmenorrhea, reduction in risk of ovarian and endometrial cancer).

For several of these methods, it is hard to keep their use private from a partner, which may place a woman at risk for contraceptive sabotage or reproductive coercion. Devices such as the diaphragm and cervical cap also need to be cleaned and stored, which may be difficult for individuals in communal living situations.

The wide-seal diaphragm and cervical cap need to be fitted in the clinic and then refitted after abortion in the second trimester or third-trimester delivery. (See 'Refitting and replacing' below.)

The diaphragm and cervical cap require concomitant use of a spermicide to maximize prevention of pregnancy. Nonoxynol-9 can be used with the diaphragm. While the vaginal pH regulator gel has not specifically been studied with the diaphragm or cap, there are no reasons to anticipate adverse outcomes with using them together, and combined use is likely more effective at preventing pregnancy compared with using the vaginal pH regulator gel alone. Nonoxynol-9 can cause vaginal irritation (eg, burning, itching, or rash or asymptomatic irritation) [5-8]. Skin breakdown associated with this irritation can be associated with an increased risk of acquiring HIV from an infected partner [9]. (See 'Vaginal spermicide and pH regulator gel' below.)

Increased risk of nonmenstrual toxic shock syndrome with diaphragm or contraceptive sponge use [10-12]. (See 'Side effects and complications' below.)

As a result of these disadvantages, individuals discontinue pericoital contraceptives because of method dissatisfaction at higher rates than they discontinue other contraceptive methods. Reported rates of discontinuation were 43 percent for diaphragm users, 64 percent for sponge users, and 58 percent for spermicide users, compared with 22 percent for IUD users and 33 percent for pill users in the same study [13]. In a survey study of current and former diaphragm users, women who stopped using the diaphragm cited difficulty inserting or removing the diaphragm (51 percent), dislike of leaving the diaphragm inside the vagina (47 percent), and wanting a more effective method for preventing pregnancy (44 percent) [14].

Selection among pericoital contraceptive methods — In deciding among the contraceptive diaphragm, cervical cap, sponge, or spermicidal agents, we discuss the method failure rates, cost, and product availability with the patient (figure 1). Additionally, comprehensive care for a sexually active patient includes STI risk assessment and a discussion of STI-preventive behaviors [15]. While the diaphragm and cervical cap may decrease risk of cervical and upper genital tract infections (eg, pelvic inflammatory disease) [3], only the external and internal condoms prevent lower genital-tract infections and transmission of HIV. (See "External (formerly male) condoms", section on 'Protection from STIs' and "Internal (formerly female) condoms", section on 'Sexually transmitted infections'.)

For patients who desire pericoital contraception over LARC or hormonal SARC methods, we suggest a diaphragm used in conjunction with spermicide. This combination has the lowest typical-use pregnancy rate compared with the other pericoital contraceptives (figure 1). However, as contraceptive selection includes many patient preferences, we defer to the patient's wishes for the final choice.

Lastly, we review the availability of emergency contraception in case the woman is concerned about method nonuse or failure (eg, the diaphragm, cervical cap, or sponge is displaced from the cervix after use). (See "Emergency contraception".)

Patients who choose pericoital contraception — Less than 1 percent of contraceptive users in the United States rely on the diaphragm, contraceptive cap, spermicides, contraceptive sponge, and the internal condom [16]. Individuals who select the diaphragm, cervical cap, sponge, or spermicides typically desire a patient-controlled and hormone-free option that is used on-demand, is inexpensive, and is readily available. A study that compared current with former diaphragm users reported that older women in monogamous relationships were more likely to choose the diaphragm and use it successfully [14]. A survey of women ages 15 to 44 between 2011 and 2013 reported that less than 0.1 percent of women were using a diaphragm during the study period [17].

DIAPHRAGM — The diaphragm is a reusable female contraceptive device consisting of a soft dome-shaped cup with a flexible rim. Diaphragms are available in single-size (one size fits most [refer to Caya instruction manual]) and multisize (must be fit to the patient) options. Diaphragms are made of silicone in the United States, but latex diaphragms may be available elsewhere. All diaphragms are designed to be used with spermicide foam, gel, or cream. (See 'Vaginal spermicide and pH regulator gel' below.)

Among individuals who practice contraception, the proportion who use the diaphragm is unclear [18]. Its use is not as popular as it once was, probably due to the higher contraceptive effectiveness, greater convenience, more privacy of hormonal contraceptives and long-acting reversible contraception (intrauterine devices and contraceptive implant), and better protection against sexually transmitted diseases afforded by external and internal condoms [16].

Efficacy — The annual pregnancy rates per 100 women for traditional diaphragms (ie, fit to the patient) when used in conjunction with nonoxynol-9 spermicide are [19]:

Twelve percent with "typical" use

Six percent with "perfect" use

These efficacy rates place the diaphragm in the second-tier effectiveness category of contraceptive options (figure 1). The diaphragm is more effective than the cervical cap and contraceptive sponge. (See 'Cervical cap' below and 'Spermicidal contraceptive sponge' below.)

The single-size diaphragm appears to have comparable efficacy with the traditional diaphragms, but the data are limited. In a trial of 450 couples randomly assigned to use the single-size or standard diaphragm, the six-month pregnancy probability per 100 women was similar (10.4 for single-size users compared with 10.7 for standard users) [20]. Extrapolation of these results to 12 months of use yields an estimated pregnancy rate of 18 per 100 woman-years for the single-size diaphragm. (See 'Single size' below.)

Diaphragm efficacy when used without nonoxynol-9 spermicide has never been studied in a well-designed trial and may be lower [21,22]. A single study including 216 diaphragm users reported lower pregnancy rates with use of nonoxynol-9 spermicide than without (12 versus 19 pregnancies per 100 women with consistent use; 21 versus 29 pregnancies per 100 women with typical use) [21]. Although these differences were not statistically significant, the low power of the study, the trend toward lower pregnancy rates with use of spermicide, and biologic plausibility support the use of spermicide with the diaphragm until stronger evidence of lack of benefit becomes available.

There are no large trials comparing the efficacy of the different diaphragm materials or spring types. (See 'Silicone diaphragms' below.)

Relative contraindications — Although most individuals can use the diaphragm, it is not a good method for those who have [1]:

Allergy or sensitivity to components (eg, latex, silicone, spermicides).

Significant pelvic organ prolapse (uterine prolapse, cystocele, rectocele, poor muscle tone of vagina) or congenital anomalies of the reproductive tract that interfere with correct placement.

Frequent urinary tract infections (UTIs).

Risk for HIV infection acquisition (unless used with a condom) since nonoxynol-9 spermicide used with diaphragms may be irritating and cause minor skin breaks that result in increased risk of virus acquisition.

Difficulty or discomfort with the insertion process.

A history of toxic shock syndrome (TSS).

Motivation or privacy issues with inserting a contraceptive near the time of coitus.

Silicone diaphragms — The silicone single-size diaphragm (commercially named Caya) has largely replaced the original silicone multisize wide-seal diaphragms. Silicone diaphragms hold up to extreme temperatures and poor storage conditions and are more inert than latex external condoms or diaphragms, so they are less likely to cause patient sensitivity or allergic reactions. As a result, latex diaphragms are no longer produced. All diaphragms require concomitant use with a spermicide to maximize pregnancy prevention. (See 'Vaginal spermicide and pH regulator gel' below.)

Single size — The single-size contraceptive diaphragm (commercial name Caya, previously known as the SILCs diaphragm) is a reusable silicone "one size fits most" device measuring 75 mm long by 67 mm wide that does not require a pelvic examination for fitting (refer to Caya instruction manual) [23]. The device is available at most major pharmacies or directly through the manufacturer with a prescription [24].

Fit — The Caya fits individuals of a wide range of weights and body mass index [25,26]. The rim bends with gentle spring force to make it easy to insert and comfortable to wear, while grip dimples and a finger dome facilitate removal (refer to Caya instruction manual). The device fits individuals who would have been fitted with a 65 to 80 mm wide-seal diaphragm (ie, approximately 80 percent of individuals) [27]. Although the single-size diaphragm does not require a pelvic examination for fitting, it does require a prescription in the United States [23]. A correctly placed Caya diaphragm has the anterior rim positioned just above the posterior surface of the symphysis pubis and the back rim is set deep in the posterior cul-de-sac, thereby covering the entire cervix. It should press against the lateral vaginal walls, and the dome should be in the correct orientation (hollowed side facing the cervix).

In a six-month trial including 300 couples who used the single-size diaphragm, 98 percent of individuals could be fitted with the device, and 94 percent could insert, correctly position, and remove the diaphragm after instruction by a clinician [20]. The successful-fit rate reported in this trial is higher than in the rate listed by the manufacturer and may reflect the relatively small sample size [27]. Eighty-two percent of couples in the trial liked the single-size diaphragm. In a study of 450 couples using the single-size diaphragm for one year, approximately 14 percent became pregnant, which is similar to the 12 percent actual-use pregnancy rate with the wide-seal diaphragms [19,28].

Efficacy — Use of the single-size diaphragm with a spermicidal gel appears to increase efficacy. In a phase I study comparing use of the single-size device with a lactic acid lubricant (commercial name Contragel), a gel of 3% nonoxynol-9, or alone, the baseline progressively motile sperm count per high-power field (PMS/HPF) in midcycle cervical mucous was 22.5 PMS/HPF [29]. The single-size diaphragm with lactic acid gel or nonoxynol-9 gel reduced the average number of PMS/HPF number to 0, while the diaphragm alone reduced the average number of PMS/HPF to 0.4. It is not yet known if this difference in PMS/HPF will impact the unintended pregnancy rate.

Wide seal — The wide-seal diaphragm has a wide outer flange of soft silicone. This creates a greater surface area of contact between the rim and the vagina and may provide a better seal compared with other types of rims. It is available with either a distortion-free spring that provides arc regardless of where the diaphragm is compressed (commercial name Milex Omniflex Style Diaphragm) or a tension-adjusted spring that folds into an arc for insertion (commercial name Milex Arcing Style Diaphragm) [30]. Both devices are available in sizes ranging from 60 to 95 mm, in 5 mm increments, and require a prescription that specifies the device size. Directions for selecting the correct size and fitting the wide seal diaphragm are listed below. (See 'Selecting the correct size' below.)

Selecting the correct size — Multisize diaphragms are manufactured in a range of sizes in 5 mm increments. The sizes most commonly carried in pharmacies range from 65 to 80 mm; larger and smaller sizes are available in some areas. Most patients are prescribed diaphragms that are 65 to 75 mm in diameter. As per the name, the single-size diaphragm is available in only one size that fits most. (See 'Single size' above.)

For multisize diaphragms, a diaphragm-fitting kit is used by the clinician to determine the best size for an individual woman's anatomy and to teach the patient how to insert and remove the device. Diaphragm kits come with a range of device sizes. The clinic-fitting diaphragm set must be disinfected between use in different patients.

The appropriate size is the largest available diaphragm that is comfortable when correctly placed. Similar to the single-sized diaphragm, a correctly placed wide-seal diaphragm fits in the space just above the posterior surface of the symphysis pubis and extends to the posterior vaginal fornix, deep in the posterior cul-de-sac, thereby covering the entire cervix. It should press against the lateral vaginal walls, and the dome should be in the correct orientation (hollowed side facing the cervix). It should not be dislodged when the patient is asked to perform a Valsalva maneuver; if the diaphragm is dislodged, the test should be repeated using the next larger size.

We avoid fitting a diaphragm in patients less than six weeks postpartum or less than two weeks following an abortion in the second trimester.

Fitting procedure — To begin, the patient places herself in the dorsal lithotomy position, as for a vaginal examination. The bladder and rectum should be empty and there should be no signs or symptoms of a vaginal or pelvic infection. Two commonly used methods of diaphragm fitting are the measurement and empiric approaches. While we prefer the empiric method, both are reasonable.

Measurement method – The clinician inserts either the index finger or both the index finger and the middle finger into the vagina, far enough so that the tip of the longest inserted finger is at the posterior vaginal fornix. Using the thumb of the same hand, the distance at the base of the finger that corresponds to the posterior surface of the symphysis pubis is marked. The hand is removed from the vagina and the distance from the tip of the finger that was in the posterior vaginal fornix to the point marked by the thumb is measured [31]. If the distance is 70 mm, then the clinician chooses a 70 mm diaphragm to test in the patient.

The test diaphragm is placed in the vagina, where it should open easily. The cervix should be completely covered by the diaphragm. Using palpation, the fit is assessed by confirming that the anterior surface of the diaphragm fits snugly behind the symphysis pubis, the posterior surface of the diaphragm reaches the posterior vaginal fornix, and undue pressure is not exerted on the vaginal mucosa.

Empiric method – The distance between the posterior vaginal fornix and the posterior surface of the symphysis is typically in the range of 70 mm [32]. Therefore, another approach to sizing a diaphragm is to insert one that is 70 mm in diameter to see if it fits properly. If this diaphragm is too small to fill the space from the posterior vaginal fornix to just above the posterior surface of the symphysis, it is removed and a 75 or 80 mm diaphragm is inserted and tested for goodness of fit. If the 70 mm diaphragm is too large, then a 65 or 60 mm diaphragm is tried.

Patient teaching at time of diaphragm initiation

Insertion and removal — After an examination to determine that the patient is a candidate for the Caya (see 'Fit' above) or to determine the correct size of the wide seal diaphragm (see 'Selecting the correct size' above), the patient is taught to partially fill the dome with a spermicide, insert the diaphragm deep into the vagina, position the diaphragm to cover the cervix with the external cervical os placed in the spermicide, and remove the diaphragm. Refer to the Caya instruction manual for more information.

Of interested patients, 94 percent are able to correctly place the Caya diaphragm following clinician instruction [20]. These steps are performed under the direct supervision of a trained provider, to ensure that the patient can successfully perform these key steps. Patients can determine their own best positions for inserting/removing the diaphragm (standing, squatting, lying down, or standing with one foot up on a stool, bathtub, or toilet) (figure 2).

The steps that need to be mastered, as per the Caya instruction manual, are:

Place a spermicide in the hollow of the dome of the diaphragm and along the rim.

Fold the diaphragm using the thumb on one side and the second and third fingers on the other. The spermicide-containing concave part of the diaphragm should be facing up and toward the cervix.

Hold the opening of the vagina apart with one hand while the other hand slides the folded diaphragm as far back as possible into the vagina, aiming toward the small of the back.

Use the index finger to push the front rim up behind the pubic bone. For the Caya diaphragm, the everted smaller dome is pushed behind the pubic bone.

Check to be sure the diaphragm is in place by feeling the front rim wedged behind the pubic bone and by feeling the cervix through the soft dome, whose hollowed side should be facing the cervix.

Remove the diaphragm by hooking one finger under the anterior rim and pulling it straight down and then out of the vagina. If suction or other factors are making it difficult to remove, a finger is inserted between the diaphragm rim and the vaginal wall to break the suction and facilitate removal.

Correct use

Prior to each use of a diaphragm, the woman should hold the diaphragm to a light and examine the dome for any puncture marks or cracks that would reduce its effectiveness. Alternatively, the dome can be filled with water and checked for leaks.

Approximately 1 tablespoon of nonoxynol-9 spermicide or a 5 g dose of the vaginal pH regulator spermicide is put into the hollow of the dome and along the circular rim. Only spermicides approved for use with a diaphragm should be used to prevent possible deterioration of the silicone. (See 'Vaginal spermicide and pH regulator gel' below.)

The diaphragm is inserted into the vagina and the position checked to ensure that the cervix is completely covered within the spermicide-containing dome. The anterior rim should be securely positioned behind the pubic bone. An additional application of foam, gel, or cream spermicide is then placed in the vagina.

Ideally, the diaphragm is inserted into the vagina less than one hour prior to sexual intercourse. If placed more than one hour before intercourse, another applicator full of fresh spermicide or vaginal pH regulator gel needs to be inserted into the vagina.

The position of the diaphragm should also be carefully checked after intercourse because it can become dislodged. If it has moved out of the proper position, it should be pushed back into position and spermicide should be reapplied into the vagina.

Each new episode of intercourse while the diaphragm is in place should be preceded by the insertion of fresh vaginal spermicide, and the diaphragm should remain in place for at least six hours after the last episode of intercourse to maximize effectiveness. It should be removed by 24 hours after initial placement to minimize the risk of vaginal irritation, UTI, and, rarely, TSS. (See 'Side effects and complications' below.)

Refer to the Caya instruction manual for more information.

Diaphragm care — With simple maintenance, diaphragms typically last approximately two years [1]. Maintenance includes:

Wash with mild soap and warm water, air-dry, and store in a clean, dry container.

Do not use powders or other products on diaphragm.

Do not use with oil-based products such as petroleum jelly or cold cream as these can damage the diaphragm. If additional lubricant is needed, water-based lubricants are used.

Diaphragms should not be shared.

Diaphragms are not typically used during menses because the risk of pregnancy is extremely low during the first five days after onset of menses.

Refitting and replacing — Caya and wide-seal diaphragm fit should be rechecked after a birth, miscarriage, or second-trimester abortion or if the patient gains or loses 4.5 kg or more (10 lbs), has pelvic surgery, has frequent UTIs, or experiences discomfort during sex. Manufacturers of silicone diaphragms recommend replacement every two years.

Side effects and complications

UTI — Diaphragm use has been associated with UTI in some individuals [1,33,34]. The mechanism is believed to be nonoxynol-9-induced changes in vaginal flora [35-38].

Proposed methods for reducing the risk of UTI include suggesting the patient urinate before inserting the diaphragm and again after intercourse, although there are no data on this practice. For patients with recurrent culture-proven UTIs, we recheck the diaphragm to ensure optimal fit. If UTIs persist despite a correctly fit diaphragm, alternatives include antimicrobial prophylaxis for those who wish to continue diaphragm use or selection of a different contraceptive method. (See "Recurrent simple cystitis in women", section on 'Antimicrobial prophylaxis in select cases' and "Contraception: Counseling and selection".)

Vaginal irritation — Vaginal irritation can result from the diaphragm itself or the nonoxynol-9 spermicide. Patients who complain of vaginal irritation or discomfort should be evaluated to ensure that the diaphragm is fit correctly. (See 'Insertion and removal' above and 'Fitting procedure' above.)

TSS — While both the diaphragm and contraceptive sponge have been associated with nonmenstrual TSS, the overall risk is very low [10-12]. In a case-control study that included 28 women with nonmenstrual TSS, most cases of diaphragm-associated TSS involved leaving the diaphragm in the vagina for more than 24 hours [10]. To reduce the risk of this serious complication, the diaphragm should be removed as soon as convenient after 6 hours from the last episode of intercourse and left in place for no more than 24 hours.

(See "Staphylococcal toxic shock syndrome".)

(See "Invasive group A streptococcal infection and toxic shock syndrome: Epidemiology, clinical manifestations, and diagnosis".)

(See "Invasive group A streptococcal infection and toxic shock syndrome: Treatment and prevention".)

(See "Toxic shock syndrome due to Paeniclostridium sordellii".)

CERVICAL CAP — The cervical cap (commercial name FemCap) is a reusable silicone cup that is described as looking like a sailor's hat (picture 1). Like diaphragms, cervical caps hold spermicide against the cervix to kill sperm and prevent them from entering the upper reproductive tract.

Efficacy — The number of individuals out of 100 who will become pregnant with typical use of the cervical cap is [39,40]:

Thirteen to 16 percent for nulliparous women

Twenty-three to 32 percent for multiparous women

This variability based on whether or not a woman has given birth is because pregnancy and delivery change the size of the cervix and the cap does not fit as well over a large cervix. As the efficacy for the cervical cap is much lower than for other contraceptive methods (figure 1), patients should be strongly encouraged to consider more effective alternatives, particularly multiparous patients.

The cervical cap is only effective when used with a spermicide because the barrier function between the cap and the cervix is not very secure. In a systematic review that included one trial of nearly 800 women, the six-month typical-use pregnancy rates were higher for FemCap users than for diaphragm users (13.5 versus 8 percent) [41,42].

Types — The cervical cap available in the United States and Europe is the FemCap, a clear silicone cap with a removal strap over the dome (picture 1). The Oves, Dumas, Vimule, and Prentif caps are no longer in production [43].

Selecting the correct size — The cervical cap size is based upon the patient's obstetric history [1,43]:

Small (22 mm) for patients who have never been pregnant

Medium (26 mm) for patients who have had an abortion or cesarean delivery

Large (30 mm) for patients who have had a full-term vaginal delivery

While having the cap fitted by a trained clinician is not required, it is preferred to ensure proper fit and teach correct insertion and removal. Caps can be purchased directly by patients through online services [24].

Use — Prior to intercourse, approximately one-quarter teaspoon of nonoxynol-9 spermicide is placed in the cap and an additional one-quarter teaspoon is placed along the rim [1,34]. The cap is then turned over and an additional one-quarter teaspoon of spermicide is placed in the groove between the dome and the brim. The insertion of the cap is then similar to insertion of a diaphragm; find a comfortable position either standing with one leg elevated, lying on one's back, or sitting (figure 2). The cervical cap is inserted with the dome/strap side down and with the long brim edge entering the vagina first so the wider aspect of the cap brim is positioned in the posterior vaginal fornix and the narrower aspect goes anteriorly. (See 'Correct use' above.)

The cap can be inserted up to six hours prior to sex. The cap must be left in the vagina for at least six hours after the last episode of intercourse, and the United States package insert states it can be left in place for up to 48 hours whereas the European package insert states it can be left in place for up to 72 hours (European approval) [43]. Prior to repeat episodes of intercourse, the user confirms correct cap position but does not remove the cap. The patient then inserts an additional dose of spermicide into the vagina.

For removal, patients should again stand on one leg, sit, or lie on their back in a comfortable position (figure 2). They should then slip a finger through the strap and press again the side of the cap to dislodge it and break the suction between the cap and the cervix. The cup should then be rotated slightly and pulled down and out of the vagina.

The cervical cap is not recommended for use during menstruation [1]. Care of the cervical cap is similar to that of a diaphragm. (See 'Diaphragm care' above.)

Relative contraindications — Individuals who are allergic or sensitive to silicone or spermicide should not use the cervical cap. (See 'Relative contraindications' above.)

Side effects and complications — The main side effects of the cervical cap are possible vaginal irritation or urinary tract infection. Toxic shock syndrome has not been reported in cervical cap users, although the risk is biologically plausible. (See 'Side effects and complications' above.)

VAGINAL SPERMICIDE AND pH REGULATOR GEL — Contraceptive vaginal gels provide on-demand contraception by either killing or immobilizing sperm. These products are inserted prior to vaginal intercourse; they do not work if inserted after intercourse [44].

Formulations — The mechanism of action varies by the product. Neither formulation is used specifically for protection against sexually transmitted infections (STIs), but the vaginal pH regulator may be protective against some infections [44]. More study is needed. (See 'Side effects and complications' below.)

Nonoxynol-9 spermicide – The spermicide nonoxynol-9 is a surfactant that destroys the sperm body and flagella and leaves sperm immobile and inactive. Nonoxynol-9 spermicides are available as a cream, film, foam, gel, tablet, or suppository and are embedded into the structure of the contraceptive sponge; all products can be inserted up to one hour prior to intercourse [1]. The suppositories, films, and tablets must be inserted at least 10 minutes prior to intercourse to allow adequate time for them to dissolve while nonoxynol-9 gel, cream, and foam products do not require a 10-minute wait time [44].

All nonoxynol-9 products can be used with external or internal condoms. The nonoxynol-9-based gel, foam, and cream formulations may be used with the diaphragm and cervical cap or may be used alone. Additionally, gel, cream, and foam products may be used immediately after method failure of another pericoital contraceptive (eg, broken condom) in an attempt to minimize an unwanted pregnancy, although this is not the optimal approach. Gel and foam products have the added benefit of providing lubrication that may be advantageous during intercourse.

Vaginal pH regulator gel – A different on-demand vaginal contraceptive, a vaginal pH regulator gel containing lactic acid-citric acid-potassium bitartrate (commercial name Phexxi, previously on the market as a lubricant under the names Amphora and ACIDFORM), was approved for contraceptive use in 2020 [45,46]. The combination maintains a lower vaginal pH of 3.5 to 4.5 even in the presence of alkaline semen (termed a "vaginal pH regulator"). The bioadhesive and viscosity-retaining properties allow this gel to coat the vagina and stay in place for up to 10 hours. The resulting acidic environment immobilizes sperm; it contains no hormones [44]. The product requires a prescription and is supplied in single-dose, prefilled vaginal applicators that contain 5 g of gel (90 mg lactic acid, 50 mg citric acid, 20 mg potassium bitartrate). Each dose is inserted into the vagina no more than one hour prior to intercourse. Dosing is repeated with every sexual act. While this gel can be used in addition to most other forms of contraception, it is not advised for use by patients who are also using hormonal contraceptive vaginal rings [45].

In the phase 3 trial, common side effects included vulvovaginal burning (20.0 percent) and vulvovaginal itching (11.2 percent) [46]. Urinary tract infection was reported by nearly 6 percent of product users while vaginal yeast infection and bacterial vaginosis were reported by nearly 3 percent of users for each. However, these rates were reduced from baseline survey data, suggesting the pH regulating gel may protect against vulvovaginal infections [45]. Nearly 43 percent of patients labeled the adverse events as mild or moderate, and less than 1 percent discontinued the method because of genitourinary symptoms [46]. This product is an alternative on-demand vaginal option for patients who wish to use a spermicide that has reduced risk of resulting in vulvovaginal or partner penile irritation [47].

Efficacy

Nonoxynol-9 – When used as the sole contraceptive method, the annual pregnancy rates per 100 women using spermicide are [19]:

Twenty percent for typical use

Eighteen percent for perfect use

While the pregnancy rate with spermicide use is lower than if no contraceptive method is used, the failure rate is higher than with other modern contraceptive options, and we educate patients who wish to avoid pregnancy about more effective methods (figure 1) [48]. There does not appear to be a difference in effectiveness based on formulation when controlling for dose of nonoxynol-9 [49]. However, patient factors such as age <35 years, multiparity, and prior frequency of unprotected intercourse are associated with higher unplanned pregnancy rates for individuals using spermicide-only as their contraceptive method [50].

Contraceptive lactic acid-citric acid-potassium bitartrate vaginal pH regulator gel – Limited data are available for this product. In a multicenter single-arm clinical trial including over 1100 participants, the seven-cycle cumulative pregnancy rate was 13.7 percent (95% CI 10.0-17.5) and the estimated Pearl Index was 27.5 pregnancies per 100 woman-years (95% CI 22.4-33.5) [45]. Just less than one-half of the participants completed the full seven cycles of the study. Cycles were excluded from analysis if back-up contraception was used, if cycles were <21 days or >35 days in length, and if no intercourse was reported.

Factors that can reduce spermicide efficacy – We educate patients that each of the following behaviors can reduce spermicide efficacy:

The patient does not wait long enough for the film and suppository formulations of nonoxynol-9 spermicide to disperse throughout the vagina before having intercourse (typically approximately 10 minutes).

Intercourse is delayed for more than one hour after administration.

A repeat dose of spermicide is not applied before each additional act of intercourse.

Use — In general, for the nonoxynol-9-containing film and suppository products, the individual inserts the spermicidal or contraceptive gel into the vagina and then waits at least 10 minutes before intercourse to allow the product to disperse. No delay is necessary for the nonoxynol-9 foam, gel, or cream or for the vaginal pH regulator gel, which can be inserted 0 to 59 minutes before intercourse. The vaginal pH regulator gel comes as a 5 g dose in a prefilled syringe (can be stored at room temperature) for vaginal administration. Both nonoxynol-9 spermicide and contraceptive vaginal gel must be reinserted before every act of intercourse. With repeated applications, the nonoxynol-9 products can leak out of the vagina. While the vaginal pH regulator is bioadhesive and does not leak out, each application is designed to buffer semen from a single act of intercourse, so it should be redosed for repeat coitus. When used with a diaphragm or cervical cap, the nonoxynol-9 spermicide product should be labeled as compatible with that device. There are slight differences in the application of nonoxynol-9 spermicidal creams, films, foams, gels, and suppositories, which are described in detail in the package insert. These products can be used during any part of the menstrual cycle.

Relative contraindications — The main contraindications are allergy or sensitivity to the chemicals in the product, and risk of exposure to STIs, including HIV infection.

Of note, nonoxynol-9 spermicide does not appear to impact pregnancy outcome in the event of accidental exposure. A meta-analysis concluded that maternal use of nonoxynol-9-containing spermicides is not associated with adverse fetal outcomes, including congenital malformations [51]. A subsequent analysis of data from the National Birth Defects Prevention Study did not find significant associations between reported first-trimester spermicide use and any birth defect, except perimembranous ventricular septal defects, which the authors noted could have been a chance finding due to multiple comparisons [52].

Side effects and complications

Irritation – Vaginal and penile irritation are reported with vaginal pH regulator gel use [1,44], though it is noncytotoxic and thus is anticipated to be less irritating than nonoxynol-9 products that are cytotoxic [45]. Male partners report irritation with the vaginal pH regulator gel at the same rate as over-the-counter lubricants [53].

STIsNonoxynol-9 spermicides do not protect against STIs, should be avoided by individuals at risk for STI exposure, and may be associated with an increased risk of acquiring HIV infection [54,55]. This association may be due to nonoxynol-9 spermicide-induced local mucosal inflammation or breakdown, which reduces mucosal immunity. This is most common among individuals who use the spermicide several times a day. In the United States, the Centers for Disease Control and Prevention recommends that patients at risk for HIV infection not use nonoxynol-9 spermicides [56]. The lactic acid component of the vaginal pH regulator decreases the risk of acquisition of chlamydia or gonorrhea [57] and may similarly inactivate HIV [4]. (See "Prevention of sexually transmitted infections", section on 'Potential risk of spermicides'.)

Bacterial vaginosisNonoxynol-9 preparations do not appear to significantly disturb the vaginal flora ecosystem, although a small increase in bacterial vaginosis-associated flora has been observed in the highest quartile of users [38]. The initial trial of contraceptive vaginal gel reported that more than 5 percent of users reported bacterial vaginosis [45]. The vaginal pH regulator spermicide supports vaginal defense systems, and this may provide protection against vaginal infections and microbial imbalances by maintaining acidity [58].

SPERMICIDAL CONTRACEPTIVE SPONGE — The nonoxynol-9 spermicidal contraceptive vaginal sponge, commercially available as the Today Sponge, is a 2.0 by 0.75 inch foam disk consisting of a polyurethane matrix impregnated with 1 gram of nonoxynol-9 that becomes activated when the sponge is moistened. A nylon loop is attached to the bottom for removal (picture 2). As of 2018, the Today Sponge is the main contraceptive sponge in production and is available in only one size and material. Because the sponge is sold over-the-counter and does not require a pelvic examination, it is a readily available option for individuals who desire immediate female-controlled contraception.

Efficacy — For patients using the contraceptive sponge, typical-use pregnancy rates are [19]:

Twelve percent for nulliparous patients

Twenty-four percent for multiparous patients

In a trial that compared the sponge with the diaphragm, the sponge was less effective and had a higher discontinuation rate [59]. Because of the higher failure rate for the sponge compared with most other contraceptive methods, most patients should be directed to more effective birth control.

Use — Before the sponge is inserted into the vagina, it is moistened with at least 2 tablespoons of tap water [1]. Once wet, the sponge is gently squeezed to distribute the water throughout and activate the spermicide. To insert the sponge, patients fold the sides inward toward the dimple (ie, away from the string) and then insert the device as far back into the vagina as they can reach, with the dimpled side facing towards the cervix. The sponge unfolds in the vagina, and its position is checked by having the patient feel around the edge of the sponge with a finger to ensure that it is covering the cervix.

The sponge, once moistened and inserted, can be used for contraception without delay. It can be inserted up to 24 hours ahead of sex but should not be worn for more than 30 hours in a row (up to 24 hours of use plus 6 hours after final sex act). The woman can have intercourse multiple times during the first 24 hours that the sponge is in place. Once removed, the sponge is discarded (it should not be flushed). It is not reusable.

The sponge does not require fitting or a prescription. It is available in pharmacies and online. The sponge can be safely used with water-based lubricants if needed.

Relative contraindications — Patients who are allergic or sensitive to sulfa, polyurethane, or the spermicide nonoxynol-9 should not use the contraceptive sponge. Patients at risk for HIV should also not use this method. Additional contraindications are similar to those for the diaphragm or nonoxynol-9 spermicide. (See 'Side effects and complications' above and 'Relative contraindications' above.)

Side effects and complications — Sponge side effects include vaginal irritation or dryness. Similar to the diaphragm, the contraceptive sponge has been associated with an increased risk of nonmenstrual toxic shock syndrome, although this complication is rare [10,11,60]. For this reason, if the sponge breaks into pieces during removal, the woman should see a clinician to ensure that all pieces have been removed. (See 'Side effects and complications' above.)

USE WITH EMERGENCY CONTRACEPTION — For all of the pericoital contraceptive methods, there is a wide gap between efficacy with typical use compared with perfect use. We therefore inform all couples using pericoital contraception about the use and nonprescription availability of emergency contraception for the female partner. Emergency contraception is indicated if there is failure of correct use of a contraceptive method. (See "Emergency contraception".)

RESOURCES FOR PATIENTS AND CLINICIANS

bedsider.org – A patient-centered, interactive online resource developed by a nonprofit organization dedicated to educating individuals about birth control methods for informed decision making.

Planned Parenthood – A nonprofit organization dedicated to reproductive health and education.

Cervical Barrier Advancement Society – A nonprofit organization dedicated to barrier contraception.

Association for Reproductive Health Professionals – ARHP is a nonprofit organization that "brings together health care professionals across disciplines and specialties for evidence-based training and network building."

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Contraception".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

Basics topics (see "Patient education: Barrier methods of birth control (The Basics)")

Beyond the Basics topic (see "Patient education: Barrier and pericoital methods of birth control (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

Contraceptive methods and mode of action – Pericoital contraception prevents functional sperm from entering the cervix and thus prevents fertilization of an egg in the female reproductive tract. These methods include the single-size diaphragm (see Caya instruction manual), traditional diaphragm, cervical cap (picture 1), and nonoxynol-9 spermicidal contraceptive sponge (picture 2) as well as spermicides alone. (See 'Mechanism of action and nomenclature' above.)

Advantages – The main advantages of pericoital contraceptives are that they are safe, woman-controlled, nonhormonal, immediately effective, reversible, portable, and relatively inexpensive. (See 'Pericoital versus other contraceptive methods' above.)

Disadvantages – The main disadvantages include lower efficacy than other contraceptive options (figure 1), lack of protection from acquiring sexually transmitted infections (STI), need for use with every episode of sex, and lack of noncontraceptive benefits associated with hormonal contraception. (See 'Pericoital versus other contraceptive methods' above.)

Side effects and complications – Side effects and complications include vaginal irritation and urinary tract infections. Cases of nonmenstrual toxic shock syndrome have also been reported in diaphragm and sponge users, although the overall risk is low. (See 'Side effects and complications' above.)

Diaphragms – Diaphragms are reusable contraceptive devices consisting of a soft dome-shaped silicone cup with a flexible rim that holds spermicide against the cervix to prevent sperm from entering the reproductive tract. The single-size diaphragm does not require fitting while the traditional diaphragms are sized to the patient. (See 'Diaphragm' above.)

Diaphragms should be used with spermicide and have typical-use yearly pregnancy rates of 12 percent for the traditional device or approximately 18 percent for the single-size device. (See 'Efficacy' above.)

Cervical cap – The cervical cap is a reusable silicone cup that holds spermicide against the cervix to immobilize sperm and prevent their entry to the female reproductive tract (picture 1). (See 'Cervical cap' above.)

This device must be used with spermicide and has typical-use yearly pregnancy rates of 13 to 16 percent for patients who have never given birth and up to 32 percent for patients who have given birth. (See 'Efficacy' above.)

The cervical cap is sized based on whether or not the patient has been pregnant or given birth vaginally. (See 'Selecting the correct size' above.)

Spermicides – Spermicides are a vaginally inserted foam, gel, film, or suppository with an active medication that stops sperm from moving. Spermicides are used alone or in conjunction with a diaphragm or cervical cap; the contraceptive sponge has nonoxynol-9 spermicide embedded in it. (See 'Vaginal spermicide and pH regulator gel' above.)

When used alone, the typical-use pregnancy rate is nearly 30 percent for nonoxynol-9, which is lower than the pregnancy rate if no contraceptive method is used (figure 1). Long-term efficacy data for patients using vaginal pH regulator spermicide are not yet available. (See 'Efficacy' above.)

Nonoxynol-9 spermicide does not protect against STIs and may increase the risk of acquiring HIV. Further study is needed on the vaginal pH regulator spermicide to prevent infection. (See 'Side effects and complications' above.)

Spermicidal contraceptive sponge – The spermicidal contraceptive sponge is a single-use 2 inch wide, 0.75 inch thick foam disk that contains 1000 mg of nonoxynol-9 and has a nylon loop attached to the bottom for removal (picture 2). (See 'Spermicidal contraceptive sponge' above.)

Typical-use yearly pregnancy rates are 12 percent for patients who have never given birth and 24 percent for patients who have given birth. (See 'Efficacy' above.)

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References

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