This chapter deals primarily with APGO Educational Topic Area:
TOPIC 33 FAMILY PLANNING
Student should be able to compare and contrast common contraceptive methods in terms of benefits, risks, mechanism of action, and effectiveness. They should be able to counsel a patient on options and identify barriers to effective contraception.
Clinical Case
A young couple returns to your obstetric office for a routine postpartum visit after normal vaginal delivery of a healthy boy. Because of your explanation of the benefits of breastfeeding for mother and baby, the mother had elected to breastfeed despite discouragement from other professional friends. With their confidence in you bolstered, the couple returns with a new, serious problem. They had planned to use condoms for contraception during breastfeeding, but now realize that the mother may breastfeed for a year or more and that they are not satisfied with the use of condoms, which distracts substantially from their sexual experience. They have never used a diaphragm, but feel it would present the same problems. As they plan to have more children, probably within the next 2 years, tubal ligation and vasectomy are inappropriate considerations. They did an Internet search for the issues of hormonal contraception during breastfeeding and found themselves bewildered by the conflicting information they found. They seek your advice.
Fifty percent of all pregnancies in the United States are unplanned, yet every year new contraceptive options are introduced touting various “improvements.” Many methods are very reliable, although no method is effective if it is not used correctly. Although there are many kinds of contraceptives, all work either by inhibiting the development or release of ova or blocking the meeting of ova and sperm. This goal is accomplished by two general mechanisms, each with many variations: 1) inhibiting the development and release of the egg (via oral contraceptives [OCPs], long-acting progesterone injection, or contraceptive patch and ring) and 2) imposing a mechanical, chemical, or temporal barrier between the sperm and egg (via condom, diaphragm, spermicide, fertility awareness, and intrauterine contraception). As a secondary mechanism, some methods also alter the ability of the fertilized egg to implant and grow (e.g., intrauterine device [IUD] used as emergency contraception). Each approach may be used individually or in combination and has its own advantages, disadvantages, risks, and benefits. Seen from another perspective, contraception allows conception to be a planned rather than an unexpected event.
Before helping any woman or couple choose among the many contraceptive options, the physician must consider two things. First, the physician must understand and be able to explain (in language the woman and partner can understand) the physiologic or pharmacologic mechanism of action, the effectiveness, the indications and contraindications, complications, and advantages and disadvantages of all the available contraceptive methods. Second, the physician must know the woman and her partner well enough to recognize personal, physical, religious, or cultural values affecting to the use of each contraceptive method under consideration and be able to help them deal with those issues using empathic evidence-based discussions, disregarding any personal bias. When done correctly, these discussions allow the couple to understand the contraceptive options and the physician to freely provide evidence-based recommendations. In this manner, an appropriate individualized contraceptive method can be chosen whose correct, regular use is highly likely. Thus, the woman and partner will be able to plan conceptions rather than experience unplanned events. When comparing all contraceptive methods, both the method failure rate (the failure rate inherent in the method if the patient uses it correctly 100% of the time) and the typical failure rate (the failure rate seen as the method is actually used by patients, that is, factoring in the mistakes in usage everyone will make from time to time and actual noncompliance) should be considered, as described in Table 26.1. By helping a woman and her partner choose a personally acceptable and biologically appropriate contraceptive method, the gap between the method failure rate and typical failure rate is minimized.
FACTORS AFFECTING THE CHOICE OF CONTRACEPTIVE METHOD
Although efficacy is important in the choice of contraceptive methods, other factors to be considered include safety; availability; cost; acceptability; and, in some cases, the patient’s physical ability to appropriately use the method. Although we tend to think of safety in terms of significant health risks, for many patients, this also includes the possibility of side effects. Women may obtain good information from reliable sites on the Internet, but there is also a huge amount of incorrect or biased information that can complicate the discussion between the physician and patient. Because good information empowers good decision making, and the converse is also true, physicians must take the time to explain the information brought in by patients. How and when the method is used can also determine the acceptability. Options vary from methods that are coitus dependent (barriers) to methods that are placed by a health care provider and last for up to 10 years (intrauterine contraception). Some women prefer methods they control. They can choose an oral daily preparation, whereas others consider the weekly transdermal (contraceptive patch) or the monthly transvaginal (contraceptive ring) forms easier to use successfully. Other women elect to use a method administered by their physician such as injections, implants, and intrauterine contraception. Sterilization (permanent contraception) is discussed in Chapter 27. Career or other life choices, as well as plans for future fertility, may influence the type and duration of the method chosen. Additionally, the couple’s feelings about which partner should take responsibility for contraception may be important.
Finally, the ability of a contraceptive method to provide some protection against sexually transmitted diseases (STDs) may also be relevant, but the physician must explain that such protection is not the main intended use of most contraceptives. Helping patients understand that, aside from condoms, contraceptive methods do not provide protection from STD is one of the most important preventive care tasks.
The physician must be sensitive to all these factors that might influence the decision and provide factual information that fits the needs of the woman and her partner. A decision tree based on this concept is presented in Figure 26.1.
DMPA, depot medroxyprogesterone acetate; IUDs, intrauterine devices.
aAmong typical couples who initiate the use of a method (not necessarily for the first time), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason.
bAmong couples who initiate the use of a method (not necessarily for the first time) and who use it perfectly (both consistently and correctly), the percentage who experience an accidental pregnancy during the first year if they do not stop use for any other reason.
Adapted from the American College of Obstetricians and Gynecologists. Guidelines for Women’s Health Care. 3rd ed. Washington, DC: American College of Obstetricians and Gynecologists; 2007:184–185.
FIGURE 26.1. Decision tree for choosing a contraceptive method.
HORMONAL CONTRACEPTIVES
For many women, “birth control” is synonymous with OCPs, OCs, or BC pills. However, hormones are also used in many other contraceptive methods, including injectable hormonal preparations, implantable hormonal rod, hormone-containing intrauterine systems, and contraceptive patches and rings.
About one third of all sexually active women in the United States use OCPs, including half of young women ages 20 to 24 years. Hormonal contraceptives have many health benefits, including decreasing a woman’s risk of ovarian and uterine cancer and providing protection against menses-associated anemia. Although hormonal contraceptive methods are associated with risks, for most women the use of one of these agents is safer than pregnancy.
Hormone-based contraceptives provide the most effective reversible pregnancy prevention available. Method (theoretical) failure rates for oral, transdermal, and transvaginal contraceptives are in the range of ≤1%. Longer-acting hormonal methods (injections, implants, and intrauterine contraception) have effectiveness rates that equal or even surpass those of sterilization. Because OCP failures are usually related to missed pills, injectable long-acting agents, patches, implants, intrauterine contraception, and rings share the additional advantage of lack of a need for daily use, which invites error.
Hormonal contraceptives do not protect against STDs. Women who use these techniques should be counseled about high-risk behaviors, safe sexual behaviors, and the need to use condoms for additional protection.
Mechanisms of Action
Most of the OCPs are combinations of an estrogen and a progestin, although there are also progestin-only products.
Combination Oral Contraceptives
Almost all combination OCP preparations contain ethinyl estradiol as the estrogen component (although a new one contains estradiol valerate) and one of the 19-nortestosterones or a spironolactone derivative (drospirenone) as the progestin product. The most prominent effect is suppression of hypothalamic gonadotropin-releasing factors with subsequent suppression of pituitary production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The progestational component provides the major contraceptive effect, acting primarily by suppressing secretion of LH and, in turn, ovulation. It also provides the added effects of thickening the cervical mucus, inhibiting sperm migration, and creating an unfavorable atrophic endometrium for implantation. The estrogenic component acts by suppressing secretion of FSH, preventing maturation of a follicle, as well as by potentiation of the action of the progestational agent. The estrogen provides an additional modest contraceptive effect, thus increasing the efficacy of this method. Importantly, estrogen also improves cycle control by stabilizing the endometrium and resulting in more regular cycles, allows for less breakthrough bleeding (bleeding not related to the menstrual period in a woman using OCPs), and is associated with greater patient satisfaction and compliance. Common progestin compounds used in hormonal contraceptives include, in descending order of biologic progestin activity, norgestrel, ethynodiol diacetate, norethindrone acetate, norethynodrel, and norethindrone. OCPs using the less androgenic agents, desogestrel, norgestimate, and drospirenone, are also available if less androgenic activity is desired. Although the progestin and estrogen components of combined OCPs act in a synergistic manner, the progestin provides more of the contraceptive effect, whereas the estrogen regularizes menstrual cycles. Knowing the difference may help in the selection of the most appropriate and acceptable formulation for a patient.
Many OCPs contain a fixed ratio of estrogen and progestin, although “phasic” formulations have been introduced that vary this ratio during the course of the month with the intent of lowering the total dose of hormones.
The classic regimen for hormonal contraception has been 21 days of active hormone (pill, patch, and ring) and 7 days of placebo or no hormones. Continuous hormone regimens are also available that produce shorter or less frequent menstrual periods, either every 3 or even 12 months. Some women may prefer this usage pattern, although they should be aware that there is a higher incidence of breakthrough bleeding in the first 12-week cycle, compared with the 4-week cycle preparations. New preparations continue to be developed with the ultimate goal of maximizing the benefits and minimizing the side effects.
Progestin-Only Oral Contraceptives
Progestin-only oral contraceptives (progestin-only “minipill”) act primarily by making the cervical mucus thick and relatively impermeable. Ovulation continues normally in about 40% of patients using the progestin-only formulation. These OCPs are of special usefulness in lactating women and women over age 40 years. In the former group, the progestin effect coincides with the prolactin-induced suppression of ovulation; in the latter group, the inherent reduced fecundity adds to the progestin effect. There is no effect on the quality or quantity of breast milk or any evidence of short- or long-term adverse effects on infants, and the progestin-only pill may be started immediately after delivery in the breastfeeding mother. The progestin-only pill is also an option for women in whom estrogen-containing formulations are contra-indicated. Because of the low dosages of progestin, the minipill must be taken at approximately the same time each day, starting on the first day of menses. If a woman is more than 3 hours late in taking the minipill, a back-up contraceptive method should be used for 48 hours. The minipill, being progestin only, offers poor cycle control.
Progestin-only OCPs are good choices for breastfeeding women and women with contraindications to estrogen, but their use must be tempered with a clear understanding that they must be used in a very consistent manner because of their limited mode of action.
Effects of Hormonal Contraceptives
Hormonal contraception affects more than just the reproductive system. Estrogens affect lipid metabolism, potentiate sodium and water retention, increase renin substrate, stimulate the cytochrome P450 system, increase sex hormone–binding globulin, and can reduce antithrombin III. Progestins increase sebum, stimulate the growth of facial and body hair, induce smooth muscle relaxation, and increase the risk of cholestatic jaundice. The newer progestational agents—desogestrel, norgestimate, and drospirenone—have less metabolic impact.
Benefits
OCPs also have many beneficial effects. Menstrual periods are predictable, shorter, and less painful, and, as a result, the risk of iron-deficiency anemia is reduced. OCP users have a lower incidence of endometrial and ovarian cancers, benign breast and ovarian disease, and pelvic infection. By decreasing conception, the risk of ectopic pregnancy is reduced, along with the complications of undesired intrauterine pregnancies.
Side Effects
Breakthrough bleeding occurs in 10% to 30% of women taking low-dose OCPs during the first 3 months of use. Although it is an especially worrisome symptom, it is not associated with decreased efficacy as long as the pill-taking regimen is maintained. The abnormal bleeding pattern is the most common reason for discontinuation of contraception, and women should be counseled to expect irregularities before hormones are initiated. If breakthrough bleeding does occur, it is best managed by encouragement and reassurance, because it usually resolves spontaneously. Breakthrough bleeding after approximately 3 months is associated with progestin-induced decidualization, with the shallow and fragile endometrium prone to asynchronous breakdown and bleeding. A short course of exogenous estrogen (1.25 mg conjugated estrogen for 7 days) given while the patient continues OCP use usually stabilizes the endometrium and stops the bleeding. Taking two or three of the pills each day is not an effective therapy for breakthrough bleeding, because the progestin component will predominate, often worsening the problem by causing further decidualization of the endometrium. Careful attention to the irregularity of menses that may occur in the first 3 months of use is important to prevent user failure based on fear about the bleeding change as a sign of something “wrong” with the use of the OCP.
Amenorrhea occurs in approximately 1% of users of low-dose OCPs in the first year of use, reaching perhaps 5% of users after several years of use. Contraceptive efficacy is maintained if the pill regimen is followed. Changing to a higher estrogen–containing pill or use of exogenous estrogen may be employed to induce bleeding, if the patient wishes. A pregnancy test should precede therapy. No treatment is indicated if the amenorrhea is acceptable to the patient.
Serious complications (such as venous thrombosis, pulmonary embolism, cholestasis and gallbladder disease, stroke, and myocardial infarction) are more likely for women using high-dose formulations and in smokers over age 35 years. However, these complications also can occur occasionally in patients taking low-dose formulations. Hepatic tumors have also been associated with the use of high-dose OCPs. Although all of these complications are 2 to 10 times more likely in pill users, they are still uncommon.
Less serious but more common side effects also depend on the dosage and type of hormones used. Estrogens may cause a feeling of bloating and weight gain, breast tenderness, nausea, fatigue, or headache. Studies have demonstrated no overall weight gain in pill users despite the patient’s perception of weight gain. Altering the dose or composition of the progestational agent used may relieve some of these minor side effects.
The therapeutic principle of contraception is to select the method providing effective contraception with the greatest margin of safety, and then to use it as long as the patient wishes contraception or beneficial menstrual-related changes. If the patient experiences new signs or symptoms while using hormonal contraception, further evaluation is necessary to choose another contraceptive method if contraception is still desired. In some cases, cessation of the chosen hormonal method or hormonal methods in general may be required (Box 26.1).
Patient Evaluation for Combined Hormonal Contraceptive Use
Before considering estrogen- and progestin-containing contraceptives for a patient, a careful evaluation is required. Not only are hormones relatively or absolutely contraindicated in some patients but also factors such as previous menstrual history may have an impact on the choice of these agents. Combined OCP use is generally contraindicated in women over age 35 years who smoke or who have had a thromboem-bolism and in women with a history of coronary artery disease, congestive heart failure, cerebral vascular disease, or migraine with or without aura (Box 26.2).
Approximately 3% of patients may experience problems with resumption of their periods after prolonged contraceptive use (postpill amenorrhea). Younger women and those who had irregular periods before the use of OCPs are more likely to experience this problem after discontinuing their use. These patients should be counseled about this potential complication.
Hormonal contraceptives may interact with other medications that the patient is taking. This interaction may reduce the efficacy of either the contraceptive or the other medications. Examples of drugs that decrease the effectiveness of contraceptives include barbiturates, benzodiazepines, phenytoin, carbamazepine, rifampin, and sulfonamides. Drugs that may show retarded biotransformation when contraceptives are also used include anticoagulants, methyldopa, phenothiazines, reserpine, and tricyclic antidepressants. Antibiotics may alter the intestinal flora and are thought to interfere with hormone absorption, but efficacy is not reduced. Before prescribing medications to women using contraceptives, the clinician should consider possible drug interactions.
Ring and Patch
The transdermal contraceptive patch contains synthetic estrogen and progestin and remains effective for an entire week (Fig. 26.2). The patient should start the patch during the first 5 days of her menstrual period and replace it weekly for 3 weeks. The fourth week is patch-free to allow a withdrawal bleed. Placement on clean, dry skin located on the buttocks, upper outer arm, or lower abdomen is recommended. Caution should be used when prescribing the patch for women weighing more than 90 kg (198 lb) because of its decreased efficacy with obesity. Side effects and contraindications are similar to those of the OCPs, although recent research has identified an increased risk of thrombosis. A complaint specific to the patch, however, includes skin irritation from adhesive residue at the application site.
FIGURE 26.2. Contraceptive patch.
FIGURE 26.3. Contraceptive ring.
The contraceptive vaginal ring releases a sustained amount of synthetic estrogen and progestin daily (Fig. 26.3). Comparable with OCPs in efficacy, the ring is associated with greater compliance because of its once-a-month usage. Placed into the vagina by the patient at the beginning of her menses, it is left in place for 3 weeks. Removal of the device results in a withdrawal bleed. The ring can be taken out of the vagina for up to 3 hours, if desired, without altering its efficacy. Because it is colorless and odorless, with a 2-in. diameter, most patients and their partners are unaware of the presence of the ring. An advantage of the ring over OCPs is a decreased incidence of breakthrough bleeding.
Because the hormones in the vaginal ring and the transdermal patch are not absorbed through the gastrointestinal tract, some of the medication interactions that occur with combined OCPs may not apply. However, metabolism still occurs in the liver; therefore, caution must be used.
Injectable Hormonal Contraceptives
Depot medroxyprogesterone acetate (DMPA) is an injectable progestin given in intramuscular or subcutaneous injections every 3 months. It maintains a contraceptive level of progestin for at least 14 weeks, providing a useful “safety” margin in case an injection is not administered within precisely 3 months. The injection should be given within the first 5 days of the current menstrual period, and, if not, a back-up method of contraception is necessary for 2 weeks. DMPA is not a sustained-release preparation, relying instead on higher peaks and sustained levels of progestin. In addition to thickening of the cervical mucus and decidualization of the endometrium, DMPA also acts by maintaining a circulating level of progestin high enough to block the LH surge and, thus, ovulation. FSH suppression does not occur with DMPA as it does with combination OCPs.
Side Effects
Recently, concerns have been raised about adverse effects of DMPA on bone mineral density (BMD) resulting from alterations in bone metabolism associated with the reduced estrogen levels. Special concern has been raised about this effect during adolescence, a critical period of bone accretion, although the decrease in BMD appears to be substantially reversible after discontinuation of this injectable contraceptive. Nonetheless, the U.S. Food and Drug Administration has added a warning to this formulation that use beyond 2 years should be carefully considered and alternate contraceptive methods be evaluated. In addition, women at special risk for osteoporosis should be especially careful when considering the use of DMPA, although dual-energy x-ray absorptiometry or other tests that evaluate BMD are not indicated. Concern about the use of DMPA in adolescents should be weighed against the advantages of compliance and effective contraception. Because the effects of DMPA on BMD are intermediate and reversible, the American College of Obstetricians and Gynecologists does not recommend that practitioners routinely limit use of DMPA to 2 years. In addition, noncontraceptive benefits of DMPA include decreased risk of endometrial carcinoma and iron-deficiency anemia. It may also improve management of pain associated with endometriosis, endometrial hyperplasia, and dysmenorrhea. As with all contraceptive options, the balance of overall risk to benefit for DMPA should be weighed on an individual patient basis (Box 26.3).
Efficacy
The efficacy of DMPA is roughly equivalent to that of sterilization (see Table 26.1) and is not affected by weight or altered by patients taking medications that alter hepatic function. Contraindications of DMPA are outlined in Box 26.3. Note that they differ from contraindications to OCPs. The lack of contraindications to hypertension, smokers over age 35 years, and other conditions makes it a viable option for women who may not be OCP candidates. DMPA injections may cause irregular bleeding, which decreases with each injection so that 80% of women are amenorrheic after 5 years. Because 25% of users discontinue DMPA within the first year of use owing to this problem, extensive preinitiation counseling and, if needed, treatment with 7 days of conjugated estrogen (1.25 mg/day) may be useful. When DMPA is discontinued, about 50% of patients resume normal menses within 6 months. Twenty-five percent do not resume menses for more than 1 year. These patients should be evaluated to detect other possible causes. DMPA is associated with a small but measurable amount of weight gain. The relatively large number of risk and benefit issues associated with the use of DMPA are often confusing to patients and require especially careful patient education to allow the best selection of this highly effective contraceptive method.
BOX 26.3 Indications and Contraindications for Depot Medroxyprogesterone Acetate Contraception
Indications
Desire for effective contraception
Women for whom compliance with other methods has been problematic
Breastfeeding
Women for whom estrogen-containing preparations are contraindicated
Women with seizure disorders
Sickle cell anemia
Anemia secondary to menorrhagia
Contraindications
• Known or suspected pregnancy
• Unevaluated vaginal bleeding
• Known or suspected malignancy of the breast
• Active thrombophlebitis, or current or past history of thromboembolic disorders, or cerebral vascular disease
• Liver dysfunction or disease
• Known sensitivity to DMPA or any of its other ingredients
Discussion
One injection every 3 months, 2-week “safety” interval (i.e., can be delayed up to 2 weeks without loss of efficacy)
No effect on quality of breast milk or on baby; increases quantity of breast milk; can be administered immediately postpartum
See above for absolute contraindications
Antiseizure medications unaffected, and sedative effects of progestins may aid in seizure control
Probable in vivo inhibition of suckling
Decreased menstrual flow
DMPA, depot medroxyprogesterone acetate.
Implantable Hormonal Contraceptives
The implant contraceptive system releases a daily dose of progestin (etonogestrel) per day. This system is easier to insert and remove than previous implantable systems (Fig. 26.4). It works primarily by thickening the cervical mucus and inhibiting ovulation. The most common side effect is irregular, unpredictable vaginal bleeding that may continue even after several months of use.
BARRIER CONTRACEPTIVES
Among the oldest and most widely used contraceptive methods are those that provide a barrier between the sperm and egg. These barriers include condoms, diaphragms, and cervical caps. Each of these methods depends on the proper use before or at the time of intercourse and, as such, is subject to a higher failure rate than noncoitus-dependent methods. This is the result of inconsistent or incorrect use as well as actual damage to the barrier material itself. For example, the latex in condoms, diaphragm, and cervica4l cap can be damaged by the application of oil-based lubricants. Despite this, these methods provide relatively good contraception and are inexpensive, and most require little or no medical consultation. In addition, condoms provide some protection against the transmission of STDs, including gonorrhea, herpes, chlamydia, human immunodeficiency virus (HIV), and human papillomavirus infection.
FIGURE 26.4. Subcutaneous contraceptive implant using etonogestrel (Nexplanon).
Condoms
Condoms are sheaths worn over the erect penis (male condom) or inside the vagina (female condom) to prevent sperm from reaching the cervix and upper genital tract. Although almost one half of all condoms are sold to women, the condom is the only reliable, nonpermanent method of contraception available to men. Condoms are widely available and inexpensive and may be made of latex; nonlatex; or, less commonly, animal membrane (usually sheep cecum). A reservoir tip reduces the likelihood of breakage. Recommending reservoir tip condoms may decrease condom breakage, a common cause of contraceptive failure with the use of this contraceptive method. Only latex condoms protect against HIV.
The condom is well tolerated, with only rare reports of skin irritation or allergic reaction. Some men complain of reduced sensation with the use of condoms, but this may actually be an advantage for those with rapid or premature ejaculation. The slippage and breakage rate in normal use is estimated at 5% to 8%. In these cases, couples should be counseled to seek medical care within 120 hours so that emergency contraceptive methods may be used.
FIGURE 26.5. The female condom. (A) Preparation for insertion. (B) Condom in proper position.
The female condom is a sheath, or vaginal liner, that fits into the vagina before intercourse (Fig. 26.5). All have slippage and breakage rates of about 3%, and, as in the case of diaphragms and cervical caps, it is recommended that they be left in place 6 to 8 hours after coitus.
Diaphragm
The diaphragm is a small, latex-covered, dome-shaped device. Proper use of a diaphragm includes applying a contraceptive jelly or cream containing spermicide into the center and along the rim of the device, which is then inserted into the vagina, over the cervix, and behind the pubic symphysis. In this position, the diaphragm covers the anterior vaginal wall and cervix.
The diaphragm can be inserted up to 6 hours before intercourse and must be left in place for 6 to 8 hours afterward, but not more than 24 hours. It may then be removed, washed, and stored. Users should be cautioned not to use talc to dry the diaphragm. If additional intercourse is desired during the 6- to 8-hour waiting time, additional spermicide should be applied without removing the diaphragm, and the waiting time should be restarted.
There are several sizes of diaphragm available and one must be fitted to the individual patient. Fit may change with significant weight change, vaginal birth, or pelvic surgery. The diaphragm should be the largest that can be comfortably inserted, worn, and removed. If the diaphragm is too small, it may slip out during coitus because of vaginal elongation; if it is too large, it may buckle, causing discomfort, irritation, and leakage. The patient must be initially instructed in the proper positioning of the diaphragm, with the correct position subsequently verified by the patient each time it is used. If the cervix can be felt through the dome of the diaphragm, the positioning is correct. In postpartum women, fitting should be done after uterine involution is complete. Correct positioning of a diaphragm is shown in Figure 26.6.
FIGURE 26.6. Diaphragm. (A) Insertion of the diaphragm. (B) Checking to ensure the diaphragm covers the cervix. (C) Diaphragm in place.
Side Effects
Women who use diaphragms are approximately twice as likely to have urinary tract infections (UTIs) as women using hormonal contraception. The increased risk of UTI may be caused by a combination of pressure against the urethra, causing urinary stasis, and an effect of spermicides on the normal vaginal flora, increasing the risk of Escherichia coli bacteriuria and infection.
Cervical Cap
The cervical cap is a smaller version of the diaphragm that is applied to the cervix itself. This method is associated with a relatively high degree of displacement as well as with cervicitis and toxic shock syndrome (TSS). It also requires considerable effort to fit. The cervical cap should also be used in conjunction with spermicide. It must be left in place for 6 hours after intercourse but not longer than 48 hours. Additional spermicide does not need to be applied with repeated acts of intercourse during that time. Correct positioning of the cervical cap is shown in Figure 26.7.
FIGURE 26.7. Cervical cap.
Sponge
The contraceptive sponge is a small, pillow-shaped sponge containing spermicide. The sponge has a dimple that is designed to fit over the cervix and remain in place during intercourse. The opposite side has a loop to facilitate removal. The sponge is available only in one size, which may explain why it is more effective in a nulliparous woman than in one who has had children. The sponge is moistened prior to insertion and can be used for repeated acts of intercourse in a 24-hour period. The sponge should be left in place for at least 6 hours after intercourse, but wearing it for more than 30 hours is not recommended because of the risk of TSS.
Spermicides
Spermicides are preparations that contain an active chemical that kills sperm as well as some type of carrier or base (e.g., gel, foam, cream, film, suppository, and tablet). In the United States, the active ingredient is nonoxynol-9. Foams and tablets should be inserted high into the vagina against the cervix, 10 to 30 minutes before each act of intercourse. The duration of maximal spermicidal effectiveness is usually no more than 1 hour. Douching should be avoided for at least 8 hours after use. There is no known association between spermicide use and congenital malformation.
Spermicides are economical, well tolerated, and effective in protection against pregnancy. Spermicides used in combination with condoms have failure rates that approach those of hormonal methods.Spermicides provide little, if any, protection against sexually transmitted infections (STIs) when used alone. For women who cannot or do not want to use hormonal contraceptives, the high effectiveness of the combined use of condoms and spermicides may be a good option.
INTRAUTERINE CONTRACEPTION
Intrauterine contraceptives, also known as intrauterine devices (IUDs), are among the most commonly used and safe methods of interval contraception worldwide. Two types of IUDs are available in the United States. Both are T shaped. One releases a small amount of levonorgestrel into the uterus, and the other releases a small amount of copper into the uterus.
Insertion
IUD insertion is best accomplished when the patient is menstruating. This timing is beneficial because it confirms the patient is not pregnant and her cervix is usually slightly open. If that timing cannot be achieved, it can be done at other times in the cycle as the patient is switching from another reliable method of contraception. The devices may also be inserted in breastfeeding women, who, in fact, demonstrate a lower incidence of postinsertional discomfort and bleeding. All IUD insertion techniques share the same basic rules: careful bimanual examination before insertion to determine the likely direction of insertion into the endometrial cavity, proper loading of the device into the inserter, careful placement to the fundal margin of the endometrial cavity, and proper inserter removal while leaving the IUD in place (Fig. 26.8). Bacteria from the endogenous cervicovaginal flora can be introduced into the uterus during IUD insertion and may cause infection. Prophylactic antibiotics have not been shown to decrease the incidence of this type of infection and are not recommended routinely. Sterile technique and a vaginal prep with povidone-iodine should be used prior to insertion of an IUD.
FIGURE 26.8. Intrauterine devices using copper or levonorgestrel.
Mechanisms of Action
The levonorgestrel-containing device primarily works by preventing the sperm and egg from meeting. It also thickens the cervical mucus and creates an unfavorable uterine environment (Fig. 26.9). The copper ions from the copper-containing device primarily work as a spermicide, inhibiting sperm motility and the acrosomal reaction necessary for fertilization (Fig. 26.10). It rarely works by inhibiting implantation and does not function as an abortifacient in normal use. The copper-containing IUD may also be used postcoitally as emergency contraception (ECP). When used in this way, it may interfere with implantation.
FIGURE 26.9. Reconstructed coronal view of uterus with appropriately placed progesterone-containing intrauterine device in endometrial cavity.
FIGURE 26.10. Reconstructed coronal view of uterus with appropriately placed copper intrauterine device in endometrial cavity.
Side Effects
A clinically important side effect of the levonorgestrel-containing IUD is a decrease in menstrual blood loss (up to 50%) and severity of dysmenorrhea. Serum progesterone levels are not affected. IUD removal is followed by rapid reversal of these effects and return to a normal intrauterine environment and normal fertility. This system is used to relieve pain related to endometriosis and adenomyosis as well as for endometrial protection for women taking hormone replacement therapy who cannot take oral progestins (Box 26.4). Increased vaginal bleeding and menstrual pain are experienced by 5% to 10% of women and often result in their request to discontinue IUD use. The progestin IUDs have a lesser incidence of this problem, because of the progestin effect on the endometrium. Thus, compared with progestin IUDs, increased menstrual flow and pain may be encountered in women choosing copper-containing devices.
Efficacy
The IUDs currently available in the United States are highly effective. The copper-containing IUD has a recommended lifespan of 10 years and demonstrates a pregnancy rate of 0.6% to 0.8%. The levonorgestrel-releasing IUD lasts for up to 5 years and has a pregnancy rate of 0.2%. The overall expulsion rate for IUDs is 1% to 5%, with the greatest likelihood in the first few months of use. Expulsion is often preceded by cramping, vaginal discharge, or bleeding, although it may be asymptomatic, with the only evidence being the observed lengthening of the IUD string or the partner feeling the device during intercourse. Patients should be counseled to see their clinician if expulsion is suspected.
Risks
There is a slight increased risk of infection the first 20 days after IUD insertion. Pelvic infection occurring 3 months or more after IUD insertion may be presumed to be an acquired STD and treated accordingly. Women at high risk for STDs may benefit from screening prior to insertion. Asymptomatic IUD users with positive cervical cultures for gonorrhea or chlamydia, or with bacterial vaginosis, should be treated promptly. The IUD may remain in place unless there is evidence of spread of the infection to the endometrium or fallopian tubes and/or failure of treatment with appropriate antibiotics.
The IUDs do not increase the overall risk of ectopic pregnancy. However, because the IUD offers greater protection against intrauterine than extrauterine pregnancy, the relative ratio of extrauterine pregnancy is greater in a woman who uses an IUD than in a woman not using contraception. Therefore, in the rare instance that a woman with an IUD in place becomes pregnant, that pregnancy would have a high risk of being extrauterine.
About 40% to 50% of patients who become pregnant with an IUD in place will spontaneously abort in the first trimester. Because of this risk, patients should be offered IUD removal if the string is visible; this is associated with a decreased spontaneous abortion rate of about 30%. If the IUD string is not visible, instrumental removal may be performed, but the risk of pregnancy disruption is increased. If the IUD is left in place, pregnancy may proceed uneventfully. There is no evidence of an increased risk of congenital anomalies with either medicated or unmedicated devices. There is, however, an approximate twofold to fourfold increase in the incidence of preterm labor and delivery.
Patient selection and skillful insertion are crucial to the successful use of the IUD as a method of contraception. The risk of STIs is the most important factor in patient selection, not age and parity. The IUD is safe for adolescents and nulliparous women.
Removal
The IUD is removed by simply pulling on the string. If the string is not visible, rotating two cotton-tip applicators in the endocervical canal will often retrieve the strings. If this is not possible, a fine probe may be inserted, the IUD felt, and then removed with an “IUD hook” or small forceps. If needed, ultrasound guidance can assist in this process. Infrequently, IUDs become embedded in the uterine wall and require hysteroscopic removal. Even less frequently, an IUD perforates the uterus (at insertion, but is not always recognized) and requires laparoscopic removal.
FERTILITY AWARENESS METHODS
“Fertility awareness methods” refer to methods that seek to prevent pregnancy by either avoiding intercourse around the time of ovulation or using knowledge of the time of ovulation to augment other methods, such as barriers and spermicides. These methods are safe, cost little, and may be more acceptable for couples who wish a natural method. However, the failure rate with typical use is high. For couples who are highly motivated and for women with a regular menstrual cycle, these methods may provide acceptable contraception.
Several methods are in use, and all are based on estimation of the woman’s fertile period. It is important to note that these methods (with the exception of lactational amenorrhea) are especially difficult to use in the postpartum period, when menstrual regularity has not yet resumed and cervical secretions are varied in appearance. Ovulation can occur as early as the fifth week postpartum.
Calendar Methods
The calendar methods (which include the standard days method) are based on calculation of a woman’s fertile period. She charts her periods for 6 months to calculate this fertile period. The first day of the fertile period is determined by subtracting 18 days from the total length of her shortest menstrual cycle. The last day of the fertile period is calculated by subtracting 11 days from the total length of her longest cycle. For a woman with regular 28-day cycles, the fertile period is from Day 10 (28 – 18) to Day 17 (28 – 11). Sex is avoided during this span. If the cycle varies from 25 to 35 days, however, the fertile period is from Day 7 (25 – 18) to Day 24 (35 – 11).
Basal Body Temperature Method
The basal body temperature method is based on temperature variations that occur around the time of ovulation. The temperature is checked daily upon awakening, but before getting out of bed, using a special thermometer and recorded on a graph. A biphasic pattern with a rise in basal body temperature of 0.5°F to 1°F is indicative of ovulation. The couple must abstain from intercourse from the end of the menstrual period until 3 days after the temperature increase.
Cervical Mucus Methods
The cervical mucus methods (which includes the two-day method) depends on the woman daily assessing her cervical mucus and noting the changes surrounding ovulation. The vagina is usually dry just after menstruation. Subsequently, a thick, sticky mucus appears. The mucus then changes to thin, “stretchy,” clear cervical mucus, called spinnbarkeit. The last day of wetness, called the “peak” day, often coincides with ovulation. The fertile period occurs with the first signs of mucus and continues until 4 days after the peak day.
Symptothermal Method
The symptothermal method combines the assessment of cervical mucus and basal body temperature methods. In addition to checking her temperature and cervical mucus, the woman also checks for other signs of ovulation, such as abdominal cramping, spotting, breast tenderness, and changes in the position or firmness of her cervix. The fertile period is from the first sign of ovulation until 3 days after temperature rise or 4 days after peak mucus.
Lactational Amenorrhea
Exclusive breastfeeding (i.e., intervals between feedings not more than 4 hours during the day and 6 hours at night with supplemental feedings limited to less than 5%–10% of total feeding) produces a natural contraceptive effect. The intensity and frequency of suckling in breastfeeding in this manner is associated with elevated prolactin levels, amenorrhea, and anovulation (see Chapter 11). Such exclusive breastfeeding is associated with more than 98% protection from pregnancy in the first 6 months postpartum and 92% over the first year. The effectiveness of this lactational method of contraception decreases when breastfeeding is less frequent (and more supplemental feeding is used). In this situation, with increasing uncertainty regarding the contraceptive effect, it is prudent to consider additional methods of contraception.
EMERGENCY CONTRACEPTION
ECP may be used for women who experience unprotected sexual intercourse. Making emergency contraception widely and easily available is one of the most important steps that can be taken to reduce the high rates of unintended pregnancy and abortion. It is estimated that the regular use of emergency contraception would prevent more than 1.5 million unintended pregnancies in the United States each year.
Combined OCP regimens used for ECP, known collectively as the Yuzpe method, were first reported by Albert Yuzpe in 1974. They required a regimen of tablets within the first 72 hours of unprotected sexual intercourse. More recently, the use of a progestin-only regimen, known as “Plan B,” was approved for behind-the-counter dispensing to women over age 17 years without a prescription. Women younger than age 17 years require a physician’s prescription to obtain the medication. Plan B and Next Choice consist of two tablets of levonorgestrel taken 12 hours apart and can be used up to 120 hours after unprotected intercourse. Plan B One Step consists of only one pill. This method is associated with a lower incidence of nausea and emesis than the Yuzpe method and with greater effectiveness. A prescription-only formulation using ulipristal acetate 30 mg, Ella, is now on the market and is indicated up to 5 days after unprotected intercourse. ECP should not be confused with the so-called abortion pills that are used to induce abortion but are not approved or appropriate for use as an ECP. All approved ECP methods act by preventing ovulation and fertilization rather than by preventing implantation and will not terminate an existing pregnancy.
The failure rate for Plan B is 1.1%. Multiple unprotected coital events or an interval greater than 72 hours may be associated with an increasing failure rate, although some evidence of success is seen up to 120 hours after unprotected intercourse. If the woman is already pregnant, these medications have no ill effect on the fetus. The amount of hormone in these regimens is not associated with alterations in clotting factors or teratogenic risk. There is no medical contrain-dication to ECP.
The copper IUD is another recommended option for ECP (except in patients with Wilson disease) and, in limited studies, has a failure rate of approximately 0.1%. An additional advantage of IUD insertion is the contraceptive effect that is provided for up to 10 years. Before using this method, a pregnancy test is required because of the risk to an implanted pregnancy.
INEFFECTIVE METHODS
The clinician must be prepared to use empathic communication skills to counsel against the routine use of folklore-based, ineffective techniques such as postcoital douching, makeshift barriers (such as food wrap), and various “contraceptive coital positions.” Coitus interruptus, or withdrawal before ejaculation, although not as effective as other methods, is somewhat effective if used regularly and certainly may be encouraged if it is the only method with which the couple is comfortable.
Clinical Follow-Up
Using empathic communication skills, you first reassure them of the “correctness” of their concern and your comfort with the issue. You then explain the various hormonal methods of contraception but quickly move to the progestin-only oral contraceptive formulations, providing an explanation of how they work, and, especially, that they are the recommended hormonal contraceptive method during breastfeeding. They are reassured and elect a progestin formulation. You subsequently explain that, unlike estrogen–progestin combination hormonal preparations, the exact timing of the use of the progestin formulation is crucial to assure effectiveness.
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