Chapter 18: Contraception

General Considerations

According to the 2006–2010 National Survey of Family Growth (NSFG), approximately one-half of all pregnancies in the United States were unintended. These rates have remained relatively unchanged since 1995. However, changes in contraceptive method use among married, non-Hispanic white women have contributed to a significant decline in the proportion of unintended births among this group. Sixty-two percent of women of reproductive age are currently using contraception. Of women using a contraceptive method, the most common methods used are the oral contraceptive pills (28%) and female sterilizations (27%). Use of intrauterine devices has increased since 1995, from 0.8% to 5.6%, whereas fewer women report that their partners are using condoms as their current most effective means of contraception. Addressing family planning and contraception is an important issue for providers of care to reproductive-age women. Because of the wide range of contraceptive options available, it is important that health care providers maintain currency with the recent advances concerning counseling, efficacy, safety, and side effects.

According to the 2006–2010 NSFG, the combined oral contraceptive pill is the leading contraceptive method among women, with 28% of women between the ages of 15–44 choosing the pill. The availability of lower-dose combination oral contraceptives (COCs) (<50 μg ethinyl estradiol) has provided many women a highly effective, safe, and tolerable method of contraception.

Combined oral contraceptives suppress ovulation by diminishing the frequency of gonodotropin-releasing hormone pulses and halting the luteinizing hormone surge. They also alter the consistency of cervical mucus, affect the endometrial lining, and alter tubal transport. Most of the antiovulatory effects of COCs derive from the action of the progestin component. The estrogen doses are not sufficient to produce a consistent antiovulatory effect. The estrogenic component of COCs potentiates the action of the progestin and stabilizes the endometrium so that breakthrough bleeding is minimized. When administered correctly and consistently, they are >99% effective at preventing pregnancy. However, failure rates are as high as 8–10% during the first year of typical use. Noncompliance is the primary reason cited for the difference between these rates, frequently secondary to side effects such as abnormal bleeding and nausea.

Hormonal Content

The estrogenic agent most commonly used in COCs is ethinyl estradiol (EE), in doses ranging from 20 to 35 μg. Mestranol, which is used infrequently, is less potent than ethinyl estradiol such that a 50-μg dose of mestranol is equivalent to 30–35 μg of ethinyl estradiol. It appears that decreasing the dose of estrogen to 20 μg reduces the frequency of estrogen-related side effects, but increases the rate of breakthrough bleeding. In addition, there may be less margin for error with low-dose preparations such that missing pills may be more likely to result in breakthrough ovulation.

Multiple progestins are used in COC formulations. Biphasic and triphasic oral contraceptives, which vary the dose of progestin over a 28-day cycle, were developed to decrease the incidence of progestin-related side effects and breakthrough bleeding, although there is no convincing evidence that multiphasics indeed cause fewer adverse effects. As with estrogens, some progestins (norethindrone and levonorgestrel) are biologically active, while others are prodrugs that are activated by metabolism. Norethindrone acetate is converted to norethindrone, and norgestimate is metabolized into several active steroids, including levonorgestrel. Progestins that do not require hepatic transformation tend to have better bioavailability and a longer serum half-life. For example, levonorgestrel has a longer half-life than norethindrone. Norgestimate and desogestrel have lower androgenic potential than other progestins.

Drospirenone, a derivative of spironolactone, differs from other progestins because it has mild antimineralocorticoid activity. Contraceptive efficacy, metabolic profile, and cycle control are comparable to other COCs. The clinical implications of the diuretic like potential of drospirenone are not yet clear. Because of its antimineralocorticoid effects and the potential for hyperkalemia, drospirenone should not be used in women with severe renal disease or hepatic dysfunction.

Combination oral contraceptives are traditionally dosed cyclically with 21 days of hormone and 7 days of placebo during which a withdrawal bleed occurs. To address the potential of escape ovulation in the lowest estrogen formulations (20 μg), many regimens reduce the number of hormone-free days to 2–4 days. Extended cycle regimens or continuous hormonal regimens are safe and acceptable forms of contraception and may be more efficacious than cyclic regimens. Extended cycle regimens result in fewer scheduled bleeding episodes; however, they also result in more unscheduled bleeding and/or spotting episodes that decrease with time. Women who may particularly benefit from these regimens are those who have symptoms exacerbated by their menses. These include women who have seizure disorders, endometriosis, menstrual headaches, premenstrual dysphoric disorder, menorrhagia, or dysmenorrhea. There are several extended cycle regimens approved by the FDA (Sasonal, Seasonique, Lybrel); however, traditionally packaged COCs may also be prescribed as extended cycle regimens. Women are advised to use the active pills and then start a new pack, ignoring the placebo pills. This regimen gives women the option of cycling as they desire, modifying the timing of individual periods on a month-by-month basis for personal reasons.

Side Effects

Side effects may be due either to the estrogen component, the progestin component, or both. Side effects attributable to progestin include androgenic effects, such as hair growth, male-pattern baldness, and nausea. Switching to an agent with lower androgenic potential may decrease or resolve these problems. Estrogenic effects include nausea, breast tenderness, and fluid retention. Weight gain is commonly assumed to be a side effect of COCs; however, multiple studies have failed to confirm a significant effect. Weight gain can be managed by switching to a different formulation; however, appropriate diet and exercise should be emphasized.

Bleeding irregularities is the side effect most frequently cited as the reason for discontinuing COCs. Patients should be counseled that irregular bleeding/spotting is common in the first 3 months of COC use and will diminish with time. Spotting is also related to missed pills. Patients should be counseled regarding the importance of taking the pill daily. If the bleeding does not appear to be related to missed pills, the patient should be evaluated for other pathology such as infection, cervical disease, or pregnancy. If this evaluation is negative, the patient may be reassured. Another approach would be to change the pill formulation to increase the estrogen or progestin component. The doses can be tailored to the time in the cycle when the bleeding occurs. If the bleeding precedes the menses, consider a triphasic pill that increases the dose of estrogen (eg, Estrostep) or progestin (eg, Ortho-Novum 7/7/7) sequentially through the cycle. If the bleeding follows the menses, consider Mircette, which has only 2 hormone-free days. Increase the estrogen and/or the progestin midcycle for midcycle bleeding (eg, Triphasil).

Combined oral contraceptives may cause a small increase in blood pressure in some patients. The risk increases with age. The blood pressure usually returns to normal within 3 months if the COC is discontinued. Both estrogens and progestins are known to affect blood pressure. Therefore, switching to a lower estrogen formulation or a progestin-only pill may not resolve the problem.

Combined oral contraceptives can be safely prescribed after a thorough medical history (including the use of tobacco products) and blood pressure documentation. While a breast examination, Pap smear, and sexually transmitted disease screening may be indicated in a particular patient, these procedures are not required before a first prescription of COCs.

Major Sequelae

The use of most oral contraceptives with <50 μg of estrogen approximately triples one’s risk of venous thromboembolism (VTE). COCs containing third-generation progestogens (desogestrel, gestodene, but not norgestimate) or the progestin drospirenone have a greater risk of VTE (1.5–3.0 fold) over COCs containing levonorgestrel. Bias and confounding in these studies do not explain the consistent epidemiologic findings of increased risk. Obesity, increasing age, and the factor V Leiden mutation are contributing risk factors. The best approach to identify women at higher risk of VTE before taking COCs is controversial. Universal screening for factor V Leiden is not cost-effective. Furthermore, family history of VTE has unsatisfactory sensitivity and positive predictive value for identifying carriers of other common defects. Although the absolute risk of VTE remains low, women using COCs containing desogestrel, gestodene, and drospirenone should be counseled regarding potential increased risk. An FDA Advisory Committee has concluded that the benefits of COCs likely outweigh the risks in most women.

The risk of thrombotic or ischemic stroke among users of COCs appears to be relatively low. There is no evidence that the type of progestin influences risk or mortality associated with ischemic stroke. The risk of ischemic stroke does appear to be directly proportional to estrogen dose, but even with the newer low-estrogen preparations there is still a slightly increased risk compared with nonusers. Hypertension and cigarette smoking interact with COC use to substantially increase the risk of ischemic stroke. The risk of hemorrhagic stroke in young women is low and is not increased by the use of COCs. History of migraine without focal neurologic signs is not a contraindication to hormonal contraception.

Current use of COCs is associated with an increased risk of acute myocardial infarction (AMI) among women with known cardiovascular risk factors (diabetes, cigarette smoking, hypertension) and among those who have not been effectively screened for risk factors, particularly for blood pressure. The risk for AMI does not increase with increasing duration of use or with past use of COCs.

Many epidemiologic studies have reported an increased risk of breast cancer among COC users. For current users of COCs, the relative risk of breast cancer compared with never-users is 1.24. This small risk persists for 10 years, but essentially disappears after this time period. Although COC users have a modest increase in risk of breast cancer, the disease tends to be localized. The pattern of disappearance of risk after 10 years coupled with the tendency toward localized disease suggests that the overall effect may represent detection bias or perhaps a promotional effect.

Noncontraceptive Health Benefits

Most studies evaluating the relationship between COCs and ovarian cancer have shown a protective effect for oral contraceptives. There appears to be a 40–80% overall decrease in risk among users, with protection beginning 1 year after starting use, with a 10–12% decrease annually in risk for each year of use. Protection persists between 15 and 20 years after discontinuation. The mechanisms by which COCs may produce these protective effects include suppression of ovulation and the suppression of gonadotropins.

The use of COCs conveys protection against endometrial cancer as well. The reduction in risk of ≤50% begins 1 year after initiation, and persists for ≤20 years after COCs are discontinued. The mechanism of action is likely reduction in the mitotic activity of endometrial cells because of progestational effects.

Numerous epidemiologic studies demonstrate that the use of COCs will reduce the risk of salpingitis by 50–80% compared with the risk to women not using contraception or who use a barrier method. The purported mechanism for protection includes progestin-induced thickening of the cervical mucus so that ascent of bacteria is inhibited, and a decrease in menstrual flow resulting in less retrograde flow to the fallopian tubes. There is no protective effect against the acquisition of lower genital tract sexually transmitted diseases. Other noncontraceptive benefits of COCs include decreased incidence of benign breast disease, relief from menstrual disorders (dysmenorrhea and menorrhagia), reduced risk of uterine leiomyomata, protection against ovarian cysts, reduction of acne, improvement in bone mineral density, and a reduced risk of colorectal cancer.

A transdermal contraceptive patch containing norelgestromin, the active metabolite of norgestimate, and ethinyl estradiol is marketed by Ortho-McNeil under the trade name Ortho-Evra. The system is designed to deliver 150 μg of norelgestromin and 20 μg of ethinyl estradiol daily directly to the peripheral circulation. The treatment regimen for each cycle is three consecutive 7-day patches (21 days) followed by one patch-free week so that withdrawal bleeding can occur. The patch can be applied to one of four sites on a woman’s body: abdomen, buttocks, upper outer arm, or torso (excluding the breast).

Ortho-Evra’s efficacy is comparable to that of COCs. Compliance with the patch is much higher than with COC, which may result in fewer pregnancies overall. However, pregnancy is more likely to occur in women weighing >198 lb. Breakthrough bleeding, spotting, and breast tenderness are slightly higher for Ortho-Evra than COCs in the first two cycles, but there is no difference in later cycles. Amenorrhea occurs in only 0.1% of patch users. Patch-site reactions occur in 2–3% of women.

Initiation of patch use is similar to initiation of COC use. Women apply the first patch on day 1 of their menstrual cycle. Another option is to apply the first patch on the Sunday after their menses begins. This becomes their patch change day. Subsequently, they change patches on the same day of the week. After three cycles they have a patch-free week during which they can expect their menses. A backup contraceptive should be used for the first 7 days of use.

The US Food and Drug Administration (FDA) requires labeling on the Ortho-Evra patch to warn health care providers and patients that this product exposes women to higher levels of estrogen than most birth control pills. Average concentration at steady state for ethinyl estradiol is ~60% higher in women using Ortho-Evra compared with women using an oral contraceptive containing 35 μg of ethinyl estradiol. In contrast, peak concentrations for ethinyl estradiol are ~25% lower in women using Ortho-Evra. In general, increased estrogen exposure may increase the risk of blood clots. The potential risks related to increased estrogen exposure with the patch should be balanced against the risk of pregnancy if patients have difficulty following the daily regimen associated with typical birth control pills.

The NuvaRing vaginal contraceptive ring is a flexible, transparent ring made of ethylene vinylacetate copolymers, delivering an average of 120 μg of etonorgestrel and 15 μg of ethinyl estradiol per day. A woman inserts the NuvaRing herself, wears it for 3 weeks, and then removes and discards the device. After one ring-free week, during which withdrawal bleeding occurs, a new ring is inserted. Continuous use has been studied; results are similar to those observed with COCs. Rarely, NuvaRing can slip out of the vagina if it has not been inserted properly or while removing a tampon, moving the bowels, straining, or with severe constipation. If the NuvaRing has been out of the vagina for >3 hours, breakthrough ovulation may occur. Patients may be counseled to check the position of the NuvaRing before and after intercourse.

Peak serum concentrations of etonorgestrel and ethinyl estradiol occur about 1 week after insertion and are 60–70% lower than peak concentrations produced by standard COCs. The manufacturer recommends using backup birth control for the first 7 days of use if not switching from another hormonal contraceptive. NuvaRing prevents pregnancy by the same mechanism as COCs. Pregnancy rates for users of NuvaRing are between 1 and 2 per 100 woman-years of use.

The side effects of NuvaRing are similar to that of COC pills; the main adverse effect is disrupted bleeding. Breakthrough bleeding/spotting occurs in 2.6–11.7% of cycles, and absence of withdrawal bleeding occurs in 0.6–3.8% of cycles. Fewer than 1–2% of women experience discomfort or reported discomfort from their partners with NuvaRing. NuvaRing is associated with increased vaginal secretions, which is a result of both hormonal and mechanical effects. Although 23% of ring users reported vaginal discharge, the normal vaginal flora appears to be maintained. The ring is not associated with either adverse cytologic effects or bacteriologic colonization of the vaginal canal. The contraindications to NuvaRing are similar to those of COCs. In addition, the ring may not be an appropriate choice for women with conditions that render the vagina more susceptible to irritation or that increase the likelihood of ring expulsion, such as vaginal stenosis, cervical prolapse, cystocele, or rectocele.

Progestin-only oral contraceptives (POPs), sometimes called the “minipill,” are not widely used in the United States. Their use tends to be concentrated in select populations, notably breastfeeding women and those with contraindications to estrogen. Two formulations of POPs are available: one containing norgestrel, the other with norethindrone. POPs appear to prevent conception through several mechanisms, including suppression of ovulation, thickening of cervical mucus, alteration of the endometrium, and inhibition of tubal transport. Efficacy of POPs requires consistent administration. The pills should be taken at the same time every day without interruption (no hormone-free week). If a pill is taken >3 hours late, a backup method of contraception should be used for the next 48 hours. No increase in the risk for thromboembolic events has been reported for POPs. The World Health Organization has deemed this contraceptive method acceptable for use in women with a history of venous thrombosis, pulmonary embolism, diabetes, obesity, or hypertension. Vascular disease is no longer considered a contraindication to use. The most common side effects of POPs are menstrual cycle disruption and breakthrough bleeding. Other common side effects include headache, breast tenderness, nausea, and dizziness. In general, POP use protects against ectopic pregnancy by lowering the chance of conception. If POP users do get pregnant, an average of 6–10% of pregnancies are extrauterine—higher than in women not using contraception. Therefore POP users should be aware of the symptoms of ectopic pregnancy.

Implanon and Nexplanon are implantable contraceptives containing the progestin etonorgestrel, the active metabolite of desogestrel, and are approved for 3 years of use. Etonorgestrel has high progestational activity but weak androgenic activity. A single rod is inserted subdermally on the inside of the upper arm. Both implants release etonorgestrel at a rate of 60–70 μg per day initially, which decreases to 25–30 μg by the end of 3 years. Etonorgestrel levels are undetectable 1 week after removal. Nexplanon is bioequivalent to Implanon but has a preloaded applicator designed to reduce the risk of insertion errors. In addition, Nexplanon is radiopaque and can therefore be located by x-ray if necessary. Like other progestin-only contraceptives, the mechanism of action is by inhibition of ovulation and thickening of cervical mucus. The implants are effective with a pregnancy rate of <1%. Irregular bleeding is the primary reason cited for discontinuation, accounting for 13–19% of discontinuations. Other adverse effects include headache, weight gain, acne, breast and abdominal pain, mood swings, depression, and decreased libido. The implants are not associated with decreased bone mineral density or venous thromboembolic disease.

Timing of insertion depends on the patient’s recent history. If she is not currently using contraception, insert during the menstrual cycle. If she is using COCs, insert during the pill-free week. If insertion occurs at other times, backup contraception is recommended for the first 7 days after insertion. Only health care providers who receive training from the manufacturer are allowed to order and insert the implant.

Injectable long-acting contraception offers users convenient, safe, and reversible birth control as effective as surgical sterilization. Depot-medroxyprogesterone acetate (DMPA) is a 3-month progestin-only formulation that can be administered by deep intramuscular injection (IM-DMPA) into the gluteus or deltoid muscle or subcutaneously (SC-DMPA). Patients using SC-DMPA can be taught to self-administer subcutaneously 4 times per year. Self-administration facilitates access to injectable contraception for many women, eliminating the need for an office visit. In addition to contraception, SC-DMPA is also indicated for the treatment of pain associated with endometriosis.

Studies have shown that DMPA acts primarily by inhibiting ovulation. With typical use, the failure rate of DMPA is 0.3 per 100 woman-years, which is comparable to that of levonorgestrel implants, copper intrauterine devices, or surgical sterilization. Neither increasing weight nor use of concurrent medications has been noted to alter efficacy, apparently because of high circulating levels of progestin.

The first injection of DMPA should be administered within 5 days of the onset of menses or within 5 days of a first-trimester abortion. If a woman is postpartum and breastfeeding, then the drug should not be administered until at least 6 weeks postdelivery. When switching from COCs, the first injection may be given any time while the active pills are being taken or within 7 days of taking the last active pill. Repeat injections of DMPA should be administered every 12 weeks. If a patient presents at 13 weeks or later, the manufacturer recommends excluding pregnancy before administering a repeat injection.

The use of DMPA has no permanent impact on fertility; however, return of fertility may be delayed after cessation of use. Fifty percent of women who discontinue DMPA to become pregnant will have conceived within 10 months of the last injection. In a small proportion of women, fertility is not reestablished until 18 months after the last injection.

Menstrual changes are the most common side effects reported by users of DMPA. After 1 year of use, approximately 75% of women receiving DMPA report amenorrhea, with the remainder reporting irregular bleeding or spotting. Some women, especially adolescents, view amenorrhea as a potential benefit of use. Women, who voice concern over this side effect, can be reassured that the amenorrhea is not harmful. Patients with persistent bleeding or spotting should be evaluated for genital tract neoplasia and infection as appropriate. If these are excluded and the symptoms are bothersome to the patient, a 1–3-month trial of low-dose estrogen can be considered. Early reinjection (eg, every 8–10 weeks) does not seem to decrease bleeding.

Other side effects attributed to DMPA include weight gain, mood swings, reduced libido, and headaches. Because of concerns regarding decreased bone mineral density (BMD) after prolonged use, the manufacturer no longer recommends use for >2 years. Reassuringly, results from several studies indicate almost complete recovery of BMD 2 years after discontinuation. Many clinicians recommend that users take supplemental calcium and vitamin D. DMPA may be used safely by smokers ≥35 years, and by other women at increased risk for arterial or venous events. Use of DMPA has not been associated with clinically significant alterations in hepatic function.

Throughout the world, the most common form of reversible contraception is the intrauterine device (IUD); however, relatively few women in the United States use IUDs (~1% compared with 15–30% in Europe and Canada), although those that do express a high degree of satisfaction. Currently there are two IUDs marketed for use in the United States. The most common IUD used is the copper-T 380A (Paragard) made of polyethylene with fine-wire copper wrapped around the stem and copper in the sleeves of each horizontal arm. It is approved for 10 years of use. The levonorgestrel IUD (Mirena) has a polyethylene frame that releases 20 μg of levonorgestrel per day for as long as 5 years. Both IUDs are visible on x-ray.

The contraceptive action of IUDs is probably a result of a combination of factors. The IUD induces an inflammatory, foreign-body reaction within the uterus that causes prostaglandin release. This release results in altered uterine activity, inhibited tubal motility, and a direct toxic effect on sperm. The copper present in the copper-T enhances the contraceptive effects by inhibiting transport of ovum and sperm. IUDs containing a progestin produce a similar effect and, in addition, thicken cervical mucus and suppress ovulation. IUDs are not abortifacients; they prevent fertilization. The IUD is one of the most effective methods of reversible contraception available. Among women who use the IUD perfectly (checking strings regularly to detect expulsion), the probability of pregnancy in the first year of use is 0.6% for the copper-T, and 0.1% for the levonorgestrel IUD. The progestational activity of the levonorgestrel IUD reduces menstrual blood loss and has been used to treat excessive uterine bleeding. The IUD may be inserted on any day of the month provided that the woman is not pregnant.

The main benefits of the IUD are a high level of effectiveness, lack of associated systemic metabolic effects, and provision of long-acting, reversible contraception. The most common reason cited for discontinuing the IUD is bleeding. Bleeding can be minimized with the use of a NSAID. However, if persistent or severe, the patient should be evaluated for infection or perforation. Patients can be reassured that the amount of bleeding and cramping usually decreases with time.

Expulsion occurs in 2–10% of women in the first year of use, with most expulsions occurring in the first 3 months. Nulliparity, abnormal amount of menstrual flow, and severe dysmenorrhea are risk factors for expulsion. In addition, the expulsion rate may be higher when the IUD is inserted at the time of the menses. Pregnancy may be the first sign of expulsion. Therefore, patients should be instructed to check for the IUD strings after each menstrual cycle. If a pregnancy does occur with an IUD in place, the IUD should be removed as soon as possible. In the presence of an IUD 50–60% of pregnancies spontaneously abort. The risk drops to 20% when the IUD is removed. Septic abortion is 26 times more common in women with an IUD. The copper-T IUD protects against ectopic pregnancy, whereas the progesterone IUD increases the risk of ectopic pregnancy almost twofold.

A common myth about IUDs is that they increase the risk of pelvic inflammatory disease (PID). However, it is now known that the risk of PID is highest in the first 20 days after insertion of an IUD, and then returns to the baseline rate. The risk is eliminated if screening and treatment of sexually transmitted infections are done before insertion. Therefore, bacterial contamination associated with the insertion process is the likely cause of infection, not the IUD itself. IUD insertion should be delayed in a woman with active cervicitis. However, women with positive Chlamydia cultures after IUD insertion are unlikely to develop PID, even with retention of the IUD, if the infection is promptly treated. The levonorgestrel IUD may lower the risk of PID by thickening cervical mucus and thinning the endometrium. Routine antibiotic prophylaxis is not recommended before IUD insertion.

The incidental finding of actinomyces on cervical cytology is more common in IUD users than in other women. If actinomyces is detected on Pap smear and the patient has signs or symptoms of PID, the IUD should be removed immediately and the patient treated with doxycycline. If the patient is asymptomatic, antibiotic treatment is not recommended and the Pap smear is repeated in 1 year.

The following conditions are contraindications to insertion of an IUD: pregnancy; current or recent cervicitis, PID, or endometritis; uterine or cervical malignancy; undiagnosed vaginal or uterine bleeding; or an IUD already in place. Conditions commonly assumed to be contraindications but are not included are diabetes mellitus, valvular heart disease, history of ectopic pregnancy (except for the levonorgestrel IUD), nulliparity, treated cervical dysplasia, irregular menses, breastfeeding, corticosteroid use, age <25 years, and multiple sexual partners. Women with multiple sexual partners should be counseled to use condoms to reduce their risk of sexually transmitted disease.

The percentage of women who used a method of contraception at their first premarital intercourse increased from 43% in the 1970s to 78% in 2006–2010. Most of this increase was due to an increase in use of the male condom at first premarital intercourse, from 22% in the 1970s to 68% in 2006–2010 (NSFG 2006–2010). Condoms are inexpensive, easy to use, and available without a prescription. Most commercially available condoms are manufactured from either latex or polyurethane. While polyurethane and latex condoms offer similar protection against pregnancy, breakage and slippage rates appear to be higher with the polyurethane condom. Natural membrane condoms (made from sheep intestine) are also available; however, they do not offer the same degree of protection from STDs. Because couples vary widely in their ability to use condoms consistently and correctly, the failure rate also varies. The percentage of women experiencing an unintended pregnancy within the first year of use ranges from 3% with perfect use to 14% with typical use. Women relying on condoms for contraception and protection from STDs should be reminded that oil-based lubricants reduce the integrity of a latex condom and facilitate breakage. Because vaginal medications (eg, for yeast infections) often contain oil-based ingredients, they can damage latex condoms as well.

There are several vaginal barrier contraceptives available that are easy to use and effective. The contraceptive efficacy of all barrier methods depends on their consistent and correct use. The percentage of women experiencing an unintended pregnancy within the first year of typical use ranges from 15% to 32%.

The female condom is a soft, loose-fitting, latex sheath with two flexible rings at either end. One ring is inserted into the vagina and lies adjacent to the cervix. The other ring remains outside of the vagina, against the perineum. Sperm is captured within the condom. The sheath is coated on the inside with a silicone-based lubricant. It is available without a prescription and is intended for one-time use. Female and male condoms should not be used together because the two condoms can adhere to one another, causing slippage and displacement. With correct and consistent use, the female condom can decrease the transmission of STDs, including HIV/AIDS.

The diaphragm is a dome-shaped latex rubber cup with a flexible rim. It is inserted, with a spermicide, into the vagina before intercourse. Once it is in position, the diaphragm provides contraceptive protection for 6 hours. If a longer interval has elapsed, insertion of additional spermicide is required. After intercourse the diaphragm must be left in place for 6 hours, but no longer than 24 hours. Use of the diaphragm has been associated with an increase risk of urinary tract infections (UTI). Spermicide exposure is an important risk factor for UTI (due to alterations in vaginal flora), although mechanical factors in diaphragm use also may contribute to the risk of UTI. Use of the diaphragm requires an appointment with a health care provider for education, fitting, and a prescription. Oil-based vaginal products should not be used with the latex diaphragm.

The cervical cap is cup-shaped silicone device that fits around the cervix. The device can be placed anytime before intercourse, with spermicide, and can be left in place for ≤48 hours. The advantages of the cervical cap over the diaphragm are that it can be left in place longer, and it is more comfortable. Like the diaphragm, the cap is manufactured in different sizes, and must be fitted by a clinician. The cap needs to be placed directly over the cervix to be effective, so it should not be used if a woman finds the placement to be difficult or uncomfortable.

The contraceptive sponge is a small, pillow-shaped polyurethane sponge containing a spermicide. The sponge protects for ≥12–24 hours, regardless of how many times intercourse occurs. After intercourse, the sponge must be left in place for ≥6 hours before it is removed and discarded. The sponge comes in one universal size and does not require a prescription.

Spermicides are an integral component of several of the barrier contraceptives. Nonoxynol-9, the active chemical agent in spermicides available in the United States, is a surfactant that destroys the sperm cell membrane. It is available in a various formulations, including gel, foam, creme, film, suppository, or tablet. Spermicide use may lower the chance of infection with a bacterial STD by as much as 25%. However, women at high risk for acquiring HIV should not use products containing nonoxynol-9. Some studies have shown that it causes vaginal lesions, which could then be entry points for HIV.

As many as half of the unintended pregnancies in the United States result from condom failure, missed birth control pills, or incorrect or inconsistent use of barrier contraception. Optimal use of emergency contraception could reduce unintended pregnancy in the United States by as much as 50%. Emergency contraception, available as combined oral contraceptives, progestin-only pills, and the copper intrauterine device, are safe and effective. When taken as directed, emergency contraceptive pills (ECPs) can reduce the risk of pregnancy by 75–89% after a single act of unprotected intercourse, while a copper IUD inserted within 5 days of intercourse can reduce the risk by 99%.

Emergency contraception (EC) is appropriate when no contraception was used or when intercourse was unprotected as a result of contraceptive accidents (eg, condom slippage). Since pill regimens involve only limited exposure to hormones, ECPs are safe. They have not been shown to increase the risk of venous thromboembolism, stroke, myocardial infarction, or other cardiovascular events. In addition, ECPs will not disrupt an implanted pregnancy and will not cause birth defects. ECPs work primarily by inhibiting ovulation, with some effects on sperm motility and thickening of cervical mucus. They will not disrupt an implanted pregnancy. Unfortunately, ECPs do not protect against sexually transmitted diseases.

Combined oral contraceptive for use as EC is frequently referred to as the Yuzpe method. Commercially available COCs containing ethinyl estradiol and levonorgestrel or norgestrel can be used as emergency contraception. Each of two doses separated by 12 hours must contain ≥100 μg ethinyl estradiol plus 0.5 mg levonorgestrel or 1.0 mg norgestrel (eg, four white Lo/Ovral pills per dose). When used correctly, the Yuzpe method decreases expected pregnancies by 75%. More specifically, 8 out of every 100 women who have unprotected intercourse once during the second or third week of their cycles will become pregnant; however, 2 out of 100 will become pregnant if the Yuzpe method is used. The most common adverse effects are nausea (50%) and vomiting (20%). Antiemetics taken 30–60 minutes before each dose help minimize these symptoms. Other side effects include delayed or early menstrual bleeding. Some women also experience heavier menses.

The most common progestin-only method of emergency contraception consists of 1.5 mg of levonorgestrel taken in one or two doses (“plan B one-step” or “next choice”). The progestin-only regimen is more effective than the Yuzpe method, preventing ≤85% of expected pregnancies. In addition, nausea occurs in <25% of patients, and vomiting is reduced to ~5% in women on the progestin-only regimen. Treatment is effective when initiated ≤5 days after unprotected intercourse, and a single 1.5-mg dose is as effective as two 0.75-mg doses 12 hours apart. Progestin-only emergency contraception is available without a prescription to women aged ≥17 years.

Ulipristal (“Ella”), a progesterone receptor modulator, was approved by the FDA as a one-dose emergency contraception in 2010. It is effective when taken ≤5 days after unprotected intercourse. Its action mechanism is delay or inhibition of ovulation. Ulipristal requires that a prescription be dispensed.

To prevent pregnancy, a copper-containing IUD can be inserted ≤5 days after unprotected intercourse. The IUD is highly effective and can be used for long-term contraception. An IUD is not recommended for anyone at risk for sexually transmitted diseases or ectopic pregnancy, or if long-term contraception is not desired. The IUD is the most effective method of EC, with failure rates of <1%.

Screening patients for ECP use is based on the time of unprotected intercourse and the date of the last normal menstrual period. There are no preexisting disease contraindications, and inadvertent use in pregnancy has not been linked to birth defects. Neither a pregnancy test nor a pelvic examination is required, although it may be done for other reasons (eg, screening for STDs). In contrast, IUD insertion for emergency contraception is an office-based procedure that requires appropriate counseling and screening as for any patient desiring an IUD for contraception.

Counseling regarding the availability of emergency contraception can occur anytime that contraception or family planning issues are discussed. It is especially appropriate if the patient is relying on barrier methods or does not have a regular form of contraception. The counseling can be reinforced when patients present with contraceptive mishaps. Information that should be discussed includes the definition of emergency contraception, indications for use, mechanism of action, lack of protection against STDs, instructions on use, and follow-up plans including ongoing contraception.

Adolescents

Adolescent pregnancy continues to be a serious public health problem in the United States. Almost 1 in 10 adolescent females becomes pregnant each year, with 74–95% described as unintended. Improved contraceptive practices has contributed to an almost 40% decrease in the teen pregnancy rate. The general approach to adolescent contraception should focus on keeping the clinician-patient encounter interactive. Several suggestions include: avoiding “yes/no” questions, keeping clinician speaking time short and focused, and avoiding the word “should.”

Abstinence deserves emphasis, especially in young teenagers. Counseling should focus not on “just say no” but rather “know how to say no.” Oral contraceptives (COCs) and condoms are the most common contraceptive methods chosen by teens. These methods should be promoted simultaneously as an approach to pregnancy and STD prevention. COC use is associated with health benefits that are especially important during adolescence including treatment for acne and menstrual cycle irregularity, decreased risk of pelvic inflammatory disease and functional ovarian cysts, and decreased dysmenorrhea. The main concern that adolescents have regarding COCs is the development of side effects, especially weight gain. They can be reassured that many studies have proven that COCs do not cause weight gain. Another issue that may contribute to the reluctance of adolescents to seek contraception is fear of a pelvic examination. Contrary to popular belief, a pelvic examination is not necessary when contraception is prescribed, especially if it will delay the sexually active teens’ access to needed pregnancy prevention. Adolescents should be counseled regarding missed pills and given anticipatory guidance about breakthrough bleeding and amenorrhea. Adolescents miss on average up to three pills per month, and the risk of contraceptive failure is twice as high among teenagers as it is among women aged >30 years. These data underscore the potential benefits of offering adolescents long-acting reversible contraception (injectables, implants, and IUDs) to reduce unintended pregnancy in this high-risk group.

In some respects, DMPA (“Depo-Provera”) is an ideal contraceptive for adolescents. The dosing schedule allows flexibility and minimal maintenance, and the failure rate is extremely low. However, concerns regarding bone loss in long-term users have prompted the recommendation that use not exceed 2 years. Although available data on adolescents are scant, they indicate that this group may be especially vulnerable to bone mineral density loss. It is not known whether bone loss before achieving peak bone density is recoverable, or to what extent the loss impacts the future risk of fracture. In addition, adolescents are likely to demonstrate other risk behaviors for bone loss, including early sexual activity, smoking, alcohol use, and poor diet choices. Until the results of larger studies are available, definitive recommendations in teenagers cannot be made.

The etonorgestrel implant has many advantages for the teen who desires contraception: ease of use, discreet, improvement of acne, reduction of dysmenorrhea, and outstanding efficacy. Despite common misperceptions, implants are not associated with increased risk of venous thromboembolism or decreased bone mineral density. Unfortunately, despite its ease of use, high efficacy, and safety, many young women choose to discontinue this method early because of problems with unpredictable irregular bleeding.

Contraceptive efficacy, convenience, and high continuation rate makes the IUD an excellent contraception method for appropriately selected adolescents. The CDC medical elligibility criteria for birth control classify women from menarche to age 20 and nulliparous women as category 2, where the advantages of using the method generally outweigh the theoretical or proven risks. The two major disadvantages include menstrual irregularity including heavier bleeding, and pelvic cramping. Both of these side effects tend to mitigate with time.

Vaginal barrier contraceptives are not ideal choices for several reasons. Many adolescents are not prepared to deal so intimately with their own bodies and do not wish to prepare so carefully for each episode of intercourse. However, they can be an effective method for highly motivated, educated adolescents.

A discussion of emergency contraception (EC) should be part of contraceptive counseling for all adolescents. To increase the availability of EC, teens may be provided with a replaceable supply of EC pills to keep at home. Several studies in adolescents have shown that direct access to emergency contraception increases its rate of use, but does not result in repetitive use. Although concern for improper use persists, women who are provided education on the method, use the method correctly, and incorrect use does not pose a health risk beyond unintended pregnancy.

Breastfeeding Women

The lactational amenorrhea method is a highly effective, temporary method of contraception. However, to maintain effective protection against pregnancy, another method must be used as soon as menstruation resumes, the frequency or duration of breastfeeds is reduced, bottle-feeding or regular food supplements are introduced, or the baby reaches 6 months of age. Other good contraceptive options for lactating women include barrier methods, progestin-only methods, or an IUD. Some experts recommend that breastfeeding women delay using progestin-only contraception until 6 weeks postpartum. This recommendation is based on a theoretical concern that early neonatal exposure to exogenous steroids should be avoided if possible. The combined pill is not a good option for lactating women because estrogen decreases breastmilk supply.

Perimenopausal Women

Women aged >40 years have the second highest proportion of unintended pregnancies, exceeded only by girls 13–14 years old. Although women still need effective contraception during perimenopause, issues including bone loss, menstrual irregularity, and vasomotor instability also need to be addressed. Oral contraceptives offer many benefits for healthy, nonsmoking perimenopausal women. They have been found to decrease the risk of postmenopausal hip fracture, regularize menses in women with dysfunctional uterine bleeding, and decrease vasomotor symptoms.

For perimenopausal women with cardiovascular risk factors, progestin-only methods may be preferred, including progestin-only pills, levonorgestrel (or copper) IUDs, contraceptive implants, and DMPA. Barrier methods or sterilization may also be appropriate in select women. Control of dysfunctional uterine bleeding can be obtained with injectable progestogens or the levonorgestrel IUD. Low-dose estrogen can be added to these methods if estrogen replacement is desired and appropriate.

Physiologically, menopause is the permanent cessation of menstruation as a consequence of termination of ovarian follicular activity. Determining the exact onset of menopause in a woman using hormonal contraception can be tricky. Many clinicians measure the level of follicle-stimulating hormone (FSH) during the pill-free interval to diagnose menopause. However, because suppression of ovulation can vary from month to month, a single FSH value is unreliable. In addition, in women using COCs, FSH levels can be suppressed even on the seventh pill-free day. Given that most women do not become menopausal until after age 50, and considering the limited utility of FSH testing, one approach to managing this transition avoids FSH testing entirely. Women continue to use their COCs until age 50–52, at which time they can discontinue use or transition to hormone replacement therapy.

The World Health Organization (WHO) has published comprehensive tables of medical conditions and personal characteristics that may affect contraceptive choice. These tables can be found online (http://whqlibdoc.who.int/publications/2010/9789241563888_eng.pdf). In 2010, the Centers for Disease Control and Prevention (CDC) adapted the WHO tables for US clinicians and patients. The CDC tables are available at http://www.cdc.gov/reproductivehealth/UnintendedPregnancy/USMEC.htm.