Ronald T. Burkman, MD
Amnon Brzezinski, MD
CONTRACEPTION
Decision making concerning fertility control is, for many people, a deeply personal and sensitive issue, often involving religious or philosophical convictions. Thus it is important for the clinician to approach the subject with particular sensitivity, empathy, maturity, and nonjudgmental behavior.
Despite the introduction of modern contraceptives, unintended or unplanned pregnancies continue to be a major problem in the United States and worldwide. According to the 2009 National Survey of Family Growth, there were a total of 6,408,000 pregnancies in the United States, of which 49.2% were unintended. Among the unintended pregnancies, nearly half result in a pregnancy termination and more than 10% in spontaneous abortion, a substantial degree of pregnancy wastage. Unintended and unplanned pregnancies have social and economic ramifications; they also have a significant impact on public health. Approximately 40% of unintended pregnancies occur among women who do not desire pregnancy yet do not use a method of contraception. Approximately 60% of unintended pregnancies occur among women using some form of birth control. Such data suggest that many women and couples are inadequately motivated to use contraception, that side effects may be problematic for some, that access may be an issue for others, or that some methods may be difficult for women to use correctly. However, encouraging is the latest report of the National Survey of Family Growth (2009) that the teenage pregnancy rate dropped 40% from 1990 to 2005, reaching an historic low of 70.6 per 1000 women aged 15–19 years. Rates fell much more for younger than for older teenagers.
Individual Indications for Birth Control
Contraception is practiced by most couples for personal reasons. Many couples use contraception to space their children or to limit their family size. Others desire to avoid childbearing because of the effects of preexisting illness on the pregnancy, such as severe diabetes or heart disease. For all of these types of decisions, clinicians must provide accurate information about the benefits and risks of both pregnancy and contraception. However, medical conditions that may substantially increase the risk of using some form of contraception usually increase the risks associated with pregnancy to an even greater extent. As a matter of public policy, some countries, especially those that are less developed, promote contraception in an effort to curb undesired population growth.
Legal Aspects of Contraception
Contraceptives are prescribed, demonstrated, and sold throughout most of the United States without restriction.
Despite high rates of unprotected intercourse and unintended pregnancy, the pros and cons of providing contraceptive information and materials to teenagers have been vigorously debated. Most states either have legislation that permits access to contraception for persons under 18 years or have not addressed the issue legislatively. There is a general consensus among physicians that teenagers should be given contraceptive advice and prescriptions within the limits of the law. Physicians must be careful to avoid imposing their own religious or moral views on their patients.
Health care providers are obliged to provide all persons requesting contraception with detailed information about use of the method(s) and its benefits, risks, and side effects so that the patient can make an informed choice relative to a particular method. Not only is the provision of this information of ethical and legal importance, but such counseling is likely to increase the likelihood that the method will be used appropriately with overall improved compliance. Documentation of the discussion with the patient and her understanding of what has been said is important both clinically and legally. In particular, when using methods that require instrumentation or surgery and that also may require intervention by a health care professional for discontinuation (eg, intrauterine contraceptive device [IUD], injectable progestin, or sterilization), signed consent forms that outline the information discussed and the patient’s understanding of it may reduce potential legal issues should a problem occur. If needed, the signed consent form serves as evidence that the patient was given counseling about use of a particular birth control method, that she appeared competent to understand what was said to her, and that she consented to receive contraceptive management in the manner specified.
METHODS OF CONTRACEPTION
The available methods of contraception can be classified in many ways. For this discussion, traditional or folk methods are coitus interruptus, postcoital douche, lactational amenorrhea, and periodic abstinence (rhythm or natural family planning). Barrier methods include condoms (male and female), diaphragm, cervical cap, vaginal sponge, and spermicides. Hormonal methods encompass oral contraceptives and injectable or implantable long-acting progestins. In addition, the IUD and sterilization (tubal ligation or vasectomy) are part of the contraceptive armamentarium. Sterilization is discussed in Chapter 46.
COITUS INTERRUPTUS
One of the oldest contraceptive methods is withdrawal of the penis before ejaculation. This process results in deposition of the semen outside the female genital tract. It has the disadvantage of demanding sufficient self-control by the man so that withdrawal precedes ejaculation. Although the failure rate probably is higher than that of most methods, reliable statistics are not available. Failure may result from escape of semen before orgasm or the deposition of semen on the external female genitalia near the vagina.
POSTCOITAL DOUCHE
Plain water, vinegar, and a number of “feminine hygiene” products are widely used as postcoital douches. Theoretically, the douche flushes the semen out of the vagina, and the additives to the water may possess some spermicidal properties. Nevertheless, sperm have been found within the cervical mucus within 90 seconds after ejaculation. Hence the method is ineffective and unreliable.
LACTATIONAL AMENORRHEA
The lactational amenorrhea method can be a highly efficient method for breastfeeding women to use physiology to space births. Suckling results in a reduction in the release of gonadotropin-releasing hormone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH). β-Endorphins induced by suckling also induce a decline in the secretion of dopamine, which normally suppresses the release of prolactin. This results in a condition of amenorrhea and anovulation. During the first 6 months, if breastfeeding is exclusive, menses are mostly anovulatory and fertility remains low. A recent World Health Organization (WHO) study on lactational amenorrhea revealed that during the first 6 months of nursing, cumulative pregnancy rates ranged from 0.9 to 1.2%. However, at 12 months, pregnancy rates rose as high as 7.4%. When using lactation as a method of birth control, the mother must provide breastfeeding as the only form of infant nutrition. Supplemental feedings may alter both the pattern of lactation and the intensity of infant suckling, which secondarily may affect suppression of ovulation. Second, amenorrhea must be maintained. Finally, the method should be practiced as the only form of birth control for a maximum of 6 months after birth. If another pregnancy is undesired, most practitioners advise lactating women to use a reliable contraceptive method starting 3 months after delivery.
Van der Wijden C, Kleijnen J, Van den Berk T. Lactational amenorrhea for family planning. Cochrane Database Syst Rev 2003:CD001329. PMID: 14583931.
MALE CONDOM
The condom, or contraceptive sheath, serves as a cover for the penis during coitus and prevents the deposition of semen in the vagina. The most common material used for male condom manufacture is latex, although available condoms are also made from polyurethane material and lamb ceca. The advantages of the condom are that it provides highly effective and inexpensive contraception as well as protection against sexually transmitted infections (STIs). Some condoms now contain a spermicide, which may offer further protection against failure, particularly if the condom breaks. Given the concern about STIs, including HIV, condom use should be recommended for all couples except those in a mutually monogamous relationship.
The condom probably is the most widely used mechanical contraceptive in the world today. Condoms made of latex or polyurethane are impervious to both sperm and most bacterial and viral organisms that cause STIs or HIV infection. However, the less commonly used lamb’s cecum condom is not impermeable to such organisms. The failure of all condoms results from imperfections of manufacture (approximately 3 in 1000); errors of technique, such as applying the condom after some semen has escaped into the vagina; and escape of semen from the condom as a result of failure to withdraw before detumescence. In typical use, failure rates with condoms range from 10 to 30% in the first year of use.
When greater contraceptive effectiveness is desired, a second method such as contraceptive vaginal jelly or foam should be used in conjunction with the condom. This combination significantly reduces the chances for condom failure due to mechanical or technical deficiencies. No association has been established between the use of vaginal contraceptives (spermicides) and the occurrence of congenital malformations if a pregnancy occurs.
FEMALE CONDOM
The female condom (Fig. 58–1) is made of thin polyurethane material with 2 flexible rings at each end. One ring fits into the depth of the vagina, and the other ring sits outside the vagina near the introitus. Female condoms have the advantage of being under the control of the female partner and of offering some protection against STDs. Significant disadvantages may be their cost and overall bulkiness. Comparisons of the female condom with other female barrier methods such as the diaphragm and cervical cap indicate that typical use failure rates are comparable. The 6-month probability of failure during perfect use of the condom is 2.6%, which is much lower than the initial prediction of 15%. Perfect use of the female condom may reduce the annual risk of acquiring HIV by more than 90%.
Figure 58–1. The female condom.
Bounds W. Female condoms. Eur J Contracept Reprod Health Care 1997;2:113–116. PMID: 9678099.
Gilliam ML, Derman RJ. Barrier methods of contraception. Obstet Gynecol Clin North Am 2000;27:841–858. PMID: 11091990.
Kulig J. Condoms: the basics and beyond. Adolesc Med 2003; 14:633–645. PMID: 15122165.
VAGINAL DIAPHRAGM
The diaphragm (Fig. 58–2) is a mechanical barrier between the vagina and the cervical canal. Diaphragms are circular rings ranging from 50–105 mm in diameter. They are designed to fit in the vaginal cul-de-sac and cover the cervix. Although the designs vary, the arcing spring version probably is the easiest for most women to use. A contraceptive jelly or cream should be placed on the cervical side of the diaphragm before insertion because the device is ineffective without it. This medication also serves as a lubricant for insertion of the device. Additional jelly should be introduced into the vagina on and around the diaphragm after it is securely in place. The diaphragm can be inserted up to 6 hours before intercourse and should be left in place for at least 6–24 hours after intercourse. When the diaphragm is of proper size (as determined by pelvic examination and trial with fitting rings) and is used according to directions, its failure rate is as low as 6 pregnancies per 100 women per year of exposure. With typical use, however, the pregnancy rate is 15–20 pregnancies per 100 woman-years. The diaphragm has the disadvantages of requiring fitting by a physician or a trained paramedical person and the necessity for anticipating the need for contraception. Weight alterations and deliveries might change the vaginal diameter. Therefore, the fit of the diaphragm to the user must be assessed yearly during the routine pelvic examination. Failures may result from improper fitting or placement and dislodgment of the diaphragm during intercourse. It cannot be used effectively by women with significant pelvic relaxation, a sharply retroverted or anteverted uterus, or a shortened vagina. As with condoms, diaphragms offer some protection against STIs. The only side effects are vaginal wall irritation, usually with initial use or if the device fits too tightly, and an increased risk of urinary tract infections due to pressure of the rim against the urethra and alterations in the composition of the vaginal flora.
Figure 58–2. The diaphragm.
Allen RE. Diaphragm fitting. Am Fam Physician 2004;69:97–100. PMID: 14727824.
CERVICAL CAP
Cervical caps (Fig. 58–3) are small, cuplike diaphragms placed over the cervix that are held in place by suction. To provide a successful barrier against sperm, they must fit tightly over the cervix. Because of variability in cervical size, individualization is essential. Tailoring the cap to fit each cervix is difficult, greatly limiting the practical usefulness of the method. In addition, many women are unable to feel their own cervix and thus have great difficulty in placing the cap correctly over the cervix. Because of these problems, the cervical cap has few advantages over the traditional vaginal diaphragm. Although some advocates of the cervical cap recommend that it remain in place for 1 or 2 days at a time, a foul discharge often develops after approximately 1 day of use. With proper use, the efficacy of the cervical cap is similar to that of the diaphragm, with dislodgment being the most frequently cited cause of failure in most reports. The cap should be left in place for 8–48 hours after intercourse, and its proper placement over the cervix should be confirmed by digital self-examination after each sexual act.
Figure 58–3. Cervical caps.
SPERMICIDAL PREPARATIONS
Spermicidal vaginal jellies, creams, gels, suppositories, vaginal sponge, and foams, in addition to their toxic effect on sperm, act as a mechanical barrier to entry of sperm into the cervical canal. The only spermicide available in the United States contains nonoxynol 9, which is a long-chain surfactant that is toxic to spermatozoa. Spermicides can be used alone or in conjunction with a diaphragm or condom. Some foam tablets and suppositories require a few minutes for adequate dispersion throughout the vagina, and failures may result if dispersion is not allowed to occur. In general, when used alone, spermicides have a failure rate of approximately 15% per year with perfect use but double that rate with typical use. These chemical agents may irritate the vaginal mucosa and external genitalia. Recent evidence indicates that spermicides containing nonoxynol 9 are not effective in preventing cervical gonorrhea, chlamydia, or HIV infection. In addition, frequent use of spermicides containing nonoxynol 9 without a barrier has been associated with genital lesions that may be linked to increased risk of HIV transmission.
Raymond EG, Chen PL, Luoto J. Contraceptive effectiveness and safety of five nonoxynol-9 spermicides: a randomized trial. Obstet Gynecol 2004;103:430–439. PMID: 14990402.
Richardson BA. Nonoxynol-9 as a vaginal microbicide for prevention of sexually transmitted infections. JAMA 2002;287:1171–1172. PMID: 11879115.
PERIODIC ABSTINENCE
It has long been known that women are fertile for only a few days of the menstrual cycle. The periodic abstinence (rhythm or natural family planning) method of contraception requires that coitus be avoided during the time of the cycle when a fertilizable ovum and motile sperm could meet in the oviduct. Fertilization takes place within the tube, and the ovum remains in the tube for approximately 1–3 days after ovulation; hence the fertile period is from the time of ovulation to 2–3 days thereafter.
Accurate prediction or indication of ovulation is essential to the success of the periodic abstinence method. Data from surveys in developed and developing countries performed during the past decade indicate the use of natural family planning methods varies from 0 to 11%. Pregnancy rates vary, but most reliable studies report 1-year life-table pregnancy rates between 10 and 25 per 100 woman-years.
1. The calendar method predicts the day of ovulation by means of a formula based on the menstrual pattern recorded over a period of several months. Ovulation ordinarily occurs 14 days before the first day of the next menstrual period. The fertile interval should be assumed to extend from at least 2 days before ovulation to no less than 2 days after ovulation. An overlap of 1–2 days of abstinence either way increases the likelihood of success. Successful use of this approach is based on the knowledge that the luteal phase of a menstrual cycle is relatively constant at 14 days for normal women. Furthermore, for this approach to be successful as the only form of contraception requires regular menstrual cycles so that the various timing schedules retain validity. Although this is the most commonly used method of periodic abstinence, it is also the least reliable, with failure rates as high as 35% in 1 year’s use.
2. A somewhat more efficacious approach to periodic abstinence is the temperature method, as more reliable evidence of ovulation can be obtained by recording the basal body temperature (BBT). The vaginal or rectal temperature must be recorded upon awakening in the morning before any physical activity is undertaken. Although it is often missed, a slight drop in temperature occurs 24–36 hours after ovulation. The temperature then rises abruptly approximately 0.3–0.4°C (0.5–0.7°F) and remains at this plateau for the remainder of the cycle. The third day after the onset of elevated temperature is considered the end of the fertile period. For reliability, care must be taken by the woman to ensure that true BBTs are recorded (ie, that temperature elevations due to other causes such as fever do not provide misleading information). A distinct limitation of this technique is that prediction of timing of ovulation in any given cycle is retrospective, making it difficult to predict the onset of the fertile period.
3. The combined temperature and calendar method uses features of the 2 methods to more accurately predict the time of ovulation. Failure rates of only 5 pregnancies per 100 couples per year have been reported in studies of well-motivated couples.
4. The cervical mucus (Billings) method uses changes in cervical mucus secretions as affected by menstrual cycle hormonal alterations to predict ovulation. Starting several days before and until just after ovulation, the mucus becomes thin and watery, whereas at other times the mucus is thick and opaque. Women using this approach are trained to evaluate their mucus on a daily basis. Success rates are similar to those described for the combined temperature and calendar method. Advantages of this approach include relative simplicity and lack of a requirement for charting. Disadvantages include difficulty in evaluating mucus in the presence of vaginal infection and the reluctance of some women to evaluate such secretions.
5. The symptothermal method, if used properly, probably is the most effective of all the periodic abstinence approaches. It combines features of both the cervical mucus and the temperature methods. In addition, symptoms that may occur just prior to ovulation, such as bloating and vulvar swelling, are used as adjuncts to ovulation.
The most accurate method of determining ovulation time is to demonstrate the LH peak in serum specimens. Because of the cost and the time required for serial measurements of LH level that are essential to indicate the abrupt rise, this method is impractical as a method of birth control. It is valuable in the treatment of infertility, however, when the optimal time for coitus or artificial insemination is of great importance.
Figure 58–4 shows the relationships among ovulation, BBT, serum levels of LH and FSH, and menses. At least 20% of fertile women have enough variation in their cycles that reliable prediction of the fertile period is impossible.
Figure 58–4. Relationships among ovulation, basal body temperature, and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) surges in the normal menstrual cycle.
Epidemiologic studies of women using periodic abstinence have suggested an increased incidence of congenital anomalies, such as anencephaly and Down syndrome, among children resulting from unplanned pregnancies. Animal experiments have shown delayed fertilization results in an increased incidence of aneuploidy and polyploidy in off-spring, thus suggesting a possible explanation for similar human fetal anomalies. However, despite a theoretical explanation for the occurrence of such birth defects, it is important to recognize that much of the data are subject to bias, and concluding that such associations have been conclusively proved would be inappropriate.
ORAL HORMONAL CONTRACEPTIVES
Oral contraceptives, when placed in general use in 1960, heralded the modern era of contraception. Oral contraceptives provide an estrogen, ethinyl estradiol, and a progestin. The most commonly used progestins in the United States are the estranes: norethindrone and norethindrone acetate; the gonanes: levonorgestrel, desogestrel, and norgestimate; and the spironolactone analogue drospirenone. When first developed, the 2 principal regimens of oral contraception were combined and sequential. The sequential method has been abandoned in the United States because several studies showed a higher than normal incidence of endometrial cancer in women using this method of contraception. In the most commonly used combined method, pills containing both estrogen and progestin are taken each day for 21 days, followed by 7 days of placebo pills, during which time most women experience withdrawal bleeding. Over the past several decades the estrogen content has been reduced by a factor of 3-fold to 4-fold, such that the current dose of ethinyl estradiol ranges between 15 and 35 μg. Similarly, the progestin content has been substantially reduced. In general use, the combined regimen is started either with the onset of the menstrual cycle or on the Sunday closest to the start of menses. Because most oral contraceptive preparations are packaged in 28-day regimens, the Sunday start approach may be easier to follow for some women. However, a good practice is to recommend use of an additional form of contraception during the first week of the cycle to maximize efficacy. Recently, some practitioners have initiated an approach in which birth control pills are started on the day of the office visit if pregnancy is unlikely. It appears this approach may reduce unwanted pregnancies. However, backup contraception is required for at least 7 days after initiation of the method. With standard oral contraceptive preparations, withdrawal bleeding can be expected within 3–5 days after completion of the 21-day regimen of active pills.
The newest approach with combined oral contraceptives is to administer active pills for a prolonged period of time, causing extended periods of amenorrhea (extended-use regimen). A preparation of 84 days active pills followed by 7 days free of was approved by the US Food and Drug Administration (FDA) in 2003. The continuous use of a 30-μg ethinylestradiol and 3-mg drospirenone formulation over 126 days was reportedly safe, efficacious, and well accepted by the users. Although this approach is designed to reduce the number of withdrawal bleeding episodes to 3–4 per year, a significant number of women experience irregular bleeding, especially during the first few cycles of use. In 2007 the FDA approved for use an extended-use oral contraceptive (ethinylestradiol/levonorgestrel 20 μg/90 μg) that is designed for 365 days of continuous use. The pregnancy rate attributable to method failure in a large noncomparative trial of healthy, sexually active women during treatment for 12 months was 15 per 2134 women (adjusted Pearl Index 1.26 per 100 women-years of use). There were no differences in pregnancy rates over 12 months between of continuous-use and cyclical use in a small, randomized, unblinded trial. In small trials, hormonal and ultrasound changes indicative of reinstated ovulation occurred within a month of discontinuation of the drug, and menstruation began again in most women within 90 days. The incidence of adverse effects was similar in continuous-use and cyclical regimens.
The serum levels of FSH and LH throughout the normal menstrual cycle are shown in Figure 58–5A. During a typical cycle under the combined oral contraceptive regimen (Fig. 58–5B), there is no rise during the first half of the cycle; thus the growth of the dominant follicle and ovulation do not occur, and there are no midcycle alterations of FSH and LH levels. Oral contraceptives change the consistency of cervical mucus, resulting in less sperm penetration; make the endometrial lining less receptive to implantation; and alter tubal transport of both sperm and oocytes. During the sequential oral contraceptive regimen (Fig. 58–5C), the estrogen stimulates LH secretion in an irregular manner. There is no concomitant early rise in FSH level when progestin is added, and another LH surge usually is produced. When a progestin-only regimen (Fig. 58–5D) is followed (see Progestin-Only Pill), there are multiple LH surges but no significant changes in FSH levels.
Figure 58–5. Serum levels (in mIU/mL) of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) during the menstrual cycle, with and without oral contraception. A: During a normal cycle without medication. B: During a typical cycle with combined medication (see text). C: During a typical cycle with sequential medication (see text). D: During progestin-only medication. (Reproduced, with permission, from Odell WD, Moyer DL. Physiology of Reproduction. St. Louis, MO: Mosby; 1971.)
A comprehensive survey of reported data indicates that the return of fertility in former oral contraceptive users (both cyclic and extended/continuous regimens) in women who stop use in order to conceive is comparable to that observed with other contraceptive methods.
Advantages
Benefits that are reasonably established include reduction in risk of ovarian and endometrial cancer, ectopic pregnancy, pelvic inflammatory disease (PID), menstrual disorders, benign breast disease, and acne. Emerging benefits include protection against bone mineral density loss, development of colorectal cancer, and progression of rheumatoid arthritis. Multiple observational studies have documented that combination oral contraceptives decrease the risk of ovarian cancer by 40–80% and endometrial cancer by approximately 50%. These effects take place after 1 year of use, and protection persists for a significant period after oral contraceptive use is discontinued. Oral contraceptives also reduce the risk of ectopic pregnancy by approximately 90% and the risk of acute salpingitis by as much as 50–80% in some studies, although other studies suggest the protection occurs to a lesser extent. However, birth control pills do not offer protection against lower tract infections such as gonorrhea or chlamydia. Oral contraceptives reduce menstrual blood loss as well as dysmenorrhea. There is a 30–50% overall decrease in benign fibrocystic conditions of the breast. Randomized placebo-controlled trials have demonstrated a reduction in acne lesions with some oral contraceptive preparations.
Disadvantages & Side Effects
Much attention has been paid to a possible relationship between the use of oral contraceptives and the incidence of thromboembolic disease, including pulmonary embolism. Use of most current combination oral contraceptives roughly triples a user’s risk of venous thromboembolism (VTE) from approximately 3 to 9 events per 100,000 users annually, although some studies of formulations containing desogestrel suggest that the risk could climb as high as 7-fold. However, it is important to recognize that even with the worst-case scenarios, the attributable risk annually is approximately 18 additional events per 100,000 users compared with nonusers of combination oral contraceptives. VTE risk is enhanced by risk factors such as recent leg trauma, pelvic surgery, stasis (but not varicose veins), and the presence of the mutation known as factor V Leiden. Although the presence of this latter clotting abnormality markedly elevates a user’s risk of VTE, the absolute risk is still low such that routine screening for the disorder among all potential oral contraceptive users would not be cost effective.
Myocardial infarction (MI) is a rare condition that occurs among combination oral contraceptive users only in the presence of risk factors such as hypertension, diabetes, severe dyslipidemia, and, in particular, cigarette smoking. Age above 35 years and smoking also act synergistically to increase risk; thus prescribing combination oral contraceptives to women over 35 years who smoke is not recommended. However, even with a 20- to 30-fold relative risk of MI among smoking combination oral contraceptive users, this risk equates to only a maximum of 500–600 events per million woman-years. However, unlike VTE, in which the case fatality rate in the reproductive age group is <1%, the case fatality rate for MI is approximately 50%.
Stroke is a rare condition among women in the reproductive age group, with hemorrhagic stroke somewhat more common than ischemic stroke. Among nonsmoking women, the rates range from 6–46 events per million woman-years; combination oral contraceptive use increases that risk only if risk factors such as age, cigarette smoking, migraine headaches (for ischemic but not hemorrhagic stroke), and especially hypertension are present. Overall, the relative risk of stroke varies between 2-fold and 10-fold, depending on the number of risk factors present.
Although cancer of the cervix among users of oral contraceptives has been a matter of concern, a major problem with many studies attempting to examine this relationship is confounding factors such as multiple sexual partners, age at first intercourse, and frequency of sexual activity and the concomitant use of barrier contraceptive methods. A recent meta-analysis determined that the risk of cervical cancer among oral contraceptive users compared with nonusers increased with duration of use, reaching a relative risk of approximately 4 after 10 years. For several decades, concern has been expressed regarding the possible association between oral contraceptive use and breast cancer. In 1996, a collaborative project representing a reanalysis of 54 studies demonstrated that for current users of oral contraceptives, the relative risk of breast cancer for users compared with women who had never used oral contraceptives was 1.24. This small increase in risk persisted for approximately 10 years after discontinuation of oral contraceptive use, with the risk essentially disappearing after that time. In addition, there was no overall effect of oral contraceptive use by dosage, specific formulation, duration of use, age at first use, age at time of cancer diagnosis, or family history of breast cancer. The pattern of disappearance of risk after 10 years coupled with a tendency toward localized disease suggests that the overall effect may represent detection bias or perhaps a promotional effect. Another recent, large population-based case-control study showed that neither current nor past use of any type of oral contraceptive increased the risk of breast cancer compared with population-based controls. Further, the results did not vary according to potential risk factors such as estrogen dose, duration of use, family history of breast cancer, or age at initiation of use. Other infrequent problems occasionally noted with oral contraceptive use include hypertension, cholelithiasis, and benign liver tumors. However, none of these problems occurs frequently enough to be of significant concern to most users.
Because the current formulations are associated with significant reductions in risk of serious sequelae, side-effect control will be of greater importance to most users in the future. Furthermore, studies have shown that compliance is affected by occurrence of side effects and that such “minor” problems, particularly spotting and breakthrough bleeding, account for approximately 40% of the discontinuations. Approximately 10–20% of women experience intermenstrual bleeding, including breakthrough bleeding and spotting, in the first few months of use. With today’s formulations, such problems stabilize after approximately 6 months and are seen in only approximately 5% of users. Missed menstrual periods or amenorrhea are relatively infrequent and of little clinical significance, except that these problems can raise concern as regarding contraceptive failure. Nausea may be seen in up to 10% of users; as with intermenstrual bleeding, this is a duration effect that declines rapidly after several months of use. Significant headaches and weight gain are far less frequent than reported with higher-dose preparations.
Contraindications for use of oral contraceptives include pregnancy; undiagnosed vaginal bleeding; prior history of VTE, MI, or stroke; women at increased risk for cardiovascular sequelae, such as active systemic lupus erythematosus, uncontrolled diabetes, or hypertension, and cigarette smokers over age 35 years; current or prior breast cancer; and active liver disease.
Because compliance and a clear understanding of how to take oral contraceptives are important to their successful use, health care providers should take the time at the initial visit to explain the packaging of the brand being prescribed, discuss the side effects, review how to start the first cycle, and discuss what to do when pills are missed. It should be emphasized that the patient package insert provides useful information on these topics. In addition, users should be encouraged to contact their provider or someone in the office or clinic who is familiar with oral contraceptive health care if problems occur. Finally, users should be advised to use alternate forms of contraception if oral contraceptive use is interrupted because of forgotten pills or the occurrence of side effects.
Table 58–1 lists the currently available oral contraceptives and their contents.
Table 58–1. Oral contraceptive agents in use.
Progestin-Only Pill (Minipill)
Several studies have demonstrated that a small daily quantity of a progestin alone, usually norethindrone or levonorgestrel, provides reasonably good protection against pregnancy without suppressing ovulation. The method has several advantages: the side effects attributable to the estrogen component of conventional oral contraceptives are eliminated because no estrogen is given, and no special sequence of pill-taking is necessary because the minipill is taken every day. Although the mechanism of action of progestin-only pills is not known, it has been postulated that the cervical mucus becomes less permeable to sperm and that endometrial activity goes out of phase so that nidation is thwarted even if fertilization does occur. In clinical trials, progestin-only oral contraceptives result in a pregnancy rate of approximately 2–7 pregnancies per 100 woman-years. Unlike combined oral contraceptives, which permit a certain margin of patient error and forgetfulness, minipill progestin agents must be taken each day promptly. Even a delay of 2–3 hours diminishes the contraceptive effectiveness for the coming 48 hours. Progestins given alone are associated with side effects, particularly irregular bleeding. Progestin-only contraceptives are ideal for women for whom estrogen is contraindicated. Ideal candidates include older women who smoke; women with sickle cell anemia, mental retardation, migraine headache, hypertension, or systemic lupus erythematosus; or women who are breastfeeding.
Emergency Contraception
Postcoital or emergency contraception is a therapy used to prevent unwanted pregnancy after unprotected intercourse or after a failure to use a contraceptive method appropriately. The major methods used for emergency contraception include combination oral contraceptives containing the progestin levonorgestrel (also known as the Yuzpe method), levonorgestrel tablets given alone, or the copper T 380A IUD. The hormonal methods prevent pregnancy by delaying or inhibiting ovulation or by disrupting the function of the corpus luteum. The usual combination hormonal formulation consists of 100 μg ethinyl estradiol and 500–600 μg levonorgestrel in several tablets administered twice, 12 hours apart. Under current recommendations, the first dose is administered within 72 hours of intercourse. The levonorgestrel-alone formulation requires administration of 750 μg of the progestin twice, also 12 hours apart. Many authorities currently recommend initial dosing within 72 hours, although data suggest this approach may be effective as long as 5 days after intercourse. Furthermore, data suggest that a single dose of 1500 μg levonorgestrel may be as effective as the 2-dose regimen. The IUD may inhibit implantation or possibly interfere with sperm function. The T 380A is inserted within 7 days from the time of unprotected intercourse.
Nausea occurs in approximately 50% and vomiting in 20% of the combination hormonal emergency contraception users. Administration of an antiemetic (eg, meclizine) 1 hour before may reduce this effect. The levonorgestrel-only approach is associated with rates of nausea and vomiting that are 50 and 70% lower than the rates experienced by combination emergency contraception users, respectively.
LONG-ACTING HORMONAL CONTRACEPTION
Depot medroxyprogesterone acetate (DMPA), an aqueous suspension of 17-acetoxy-6-methyl progesterone, has been used as a contraceptive in the United States for at least 4 decades. The usual dose is 150 mg administered intramuscularly into the gluteus maximus or deltoid every 3 months. The mechanisms of action include suppression of ovulation by suppressing the surge of gonadotropins, thickening cervical mucus to impede ascent of sperm, and thinning of the endometrium such that implantation of a blastocyst is less likely. Although labeled as effective for up to 13 weeks, the contraceptive activity actually persists for approximately 4 months after an injection, allowing some leeway for providers to schedule follow-up injections. During 1 year of use, the perfect use failure rate is 0.3 pregnancies per 100 woman-years, whereas the failure rate with typical use is 3 pregnancies per 100 woman-years.
Use of DMPA is associated with several health benefits. The risk of ectopic pregnancy is significantly lower among users compared to women who do not use contraception. The risk of endometrial cancer is reduced by as much as 80%, an effect that is long term and increases with duration of use. Studies have shown as much as a 70% reduction in the frequency of sickle cell crises; the mechanism for this effect is not known. Some women with endometriosis have improvement of symptoms with use of DMPA.
Use of DMPA does not increase the risk for arterial or venous disease. The most significant potential risk associated with DMPA use is a reduction in bone mineral density. Overall, prospective studies of at least 1 year’s duration have shown a maximum reduction of 1.5–2.3% in bone mineral density. No studies have shown any increase in fracture risk. Finally, retrospective studies have shown improvement in bone mineral density when DMPA was discontinued. Until further data become available, adequate calcium intake should be encouraged for DMPA users, particularly young patients and longer term users. Irregular bleeding and prolonged menstrual flow are not uncommon during the first 6 months of use. However, with continued use, many women become amenorrheic, and up to 70% of users experience no menses after 1 year. Mood change and depression have been reported in association with DMPA use. However, most studies are uncontrolled. Although earlier studies suggested DMPA users gained an average of 5 lb after 1 year of use, a recent randomized clinical trial demonstrated that DMPA was not associated with significant weight gain or changes in variables that might lead to weight gain. Finally, when DMPA users stop injections in an effort to achieve pregnancy, the return to baseline fertility may take an average of 10 months.
Implants
Although no implantable contraceptives currently are available in the United States, clinical trials of a single-rod implant 4 cm long and 2 mm in diameter have been completed. This system releases etonogestrel, the major metabolite of desogestrel, and maintains its efficacy for up to 3 years. The rod usually is inserted in the upper arm, using a trocar. Removal is easier than with other implants because it is a single-rod system. The likely mechanism of action is similar to that of DMPA. Overall efficacy is extremely high, with no reported pregnancies in more than 70,000 cycles of use. No major complications have been reported to date. Side effects include menstrual abnormalities and weight gain.
Vaginal Ring
The vaginal ring (Fig. 58–6) is approximately 5 cm in diameter and 4 mm thick. The ring is flexible. It releases ethinyl estradiol and etonogestrel at fairly constant rates. The ring is worn for 3 weeks per month, although the ring’s reservoir contains enough contraceptive steroid for approximately 14 more days. The ring maintains its efficacy even if it is removed for up to 3 hours, although it is designed to be left in place even during intercourse. Users are instructed to insert the ring high into the vagina; fitting by a health professional is not required. The overall pregnancy rate over 1 year of use is 0.65 pregnancies per 100 woman-years.
Figure 58–6. The vaginal ring.
No published data indicate the rates of major side effects or potential noncontraceptive benefits. However, because the vaginal ring contains steroids that are used in combination oral contraceptives, rates of serious side effects may be similar, and some of the noncontraceptive benefits may accrue to users of this method. Minor side effects are similar to those seen in users of combination oral contraceptives, although the frequency of breakthrough bleeding and spotting appears lower. Approximately 10–15% of users report vaginal-related symptoms, such as slight discomfort, a sensation of a foreign body, leukorrhea, vaginitis, or coital problems. There are reports that the ring might be used in an extended regimen, although this regimen was not yet approved by regulatory institutions.
Transdermal Patch
The transdermal contraceptive patch is 20 cm2, roughly the size of a small adhesive-back (Post-It) pad consisting of 3 layers. The transdermal contraceptive patch is designed to deliver norelgestromin, the active metabolite of norgestimate, and ethinyl estradiol daily for a 7-day period. After 7 days, the patch is removed and a new patch is applied to another skin site. Three consecutive 7-day patches are applied in a typical cycle, followed by a 7-day patch-free period to allow withdrawal bleeding. Application sites include the buttocks, lower abdomen, upper outer arm, and upper torso, except for the breasts. Because this is a combination steroid preparation, the same contraindications noted for combination oral contraceptives use apply.
The transdermal contraceptive patch has a method use rate of 0.70 and a typical use rate of 0.88 pregnancies per 100 woman-years. These rates are comparable to pregnancy rates achieved with current oral contraceptives. However, a failure rate approaching the typical use failure rate seen with combination oral contraceptive users was noted for women weighing over 198 pounds who used the patch.
Although few reports have documented the rates of serious adverse events, one should assume that the events and risks will be similar to those noted for combination oral contraceptives. To date, 1 published study has indicated that the risk of venous thromboembolism is similar to that of an oral contraceptive. Similarly, no data on noncontraceptive benefits are available. The frequency of side effects such as headache and nausea are similar to that seen among users of combination oral contraceptives, although contraceptive patch users have application site reactions, more breast symptoms (only during the first 2 cycles), and more dysmenorrhea than combination oral contraceptive users. The pattern of breakthrough bleeding and spotting with the transdermal contraceptive patch is similar to that seen with oral contraceptive users. No evidence indicates that use of the patch influences body weight. Among users, 1.8% of women required replacement for complete detachment and 2.9% became partially detached. Detachment rates were similar for women living in warm, humid climates and for women who were subjected to vigorous exercise, swimming, and sauna use compared with other users. When patches do become detached, users should attempt to reattach them if possible, without using ancillary adhesives or tape. If detachment has occurred for 24 hours or less, the cycle continues as usual, with the patch changed on the previously determined change day. If detachment has occurred for more than 24 hours, a new patch should be applied, backup contraception should be used for 1 week, and the day that the new patch is applied now becomes the patch change day.
Anderson FD, Hait H. A multicenter, randomized study of an extended cycle oral contraceptive. Contraception 2003;68: 89–96. PMID: 12954519.
Audet M, Moreau M, Koltun WD, et al. Evaluation of contraceptive efficacy and cycle control of a transdermal contraceptive patch vs an oral contraceptive. JAMA 2001;285:2347–2354. PMID: 11343482.
Barreiros FA, Guazzelli CA, de Araújo FF, Barbosa R. Bleeding patterns of women using extended regimens of the contraceptive vaginal ring. Contraception 2007;75:204–208. PMID: 17303490.
Barnhart KT, Schreiber CA. Return to fertility following discontinuation of oral contraceptives. Fertil Steril 2009;91:659–663. PMID: 19268187.
Burkman RT. Cardiovascular issues with oral contraceptives: evidenced-based medicine. Int J Fertil Womens Med 2000;45: 166–174. PMID: 10831186.
Burkman RT. The transdermal contraceptive system. Am J Obstet Gynecol 2004;190:S49.
Burkman R, Schlesselman JJ, Zieman M. Safety concerns and health benefits associated with oral contraception. Am J Obstet Gynecol 2004;190:S5–S53. PMID: 15105798.
Croxatto HB. Clinical profile of Implanon: a single-rod etonogestrel contraceptive implant. Eur J Contracept Reprod Health Care 2000;5(suppl 2):21–28. PMID: 11246604.
Darney PD. Implantable contraception. Eur J Contracept Reprod Health Care 2000;5(suppl 2):2–11. PMID: 11246603.
Dunn S, Guilbert E, Lefebvre G, et al. Emergency contraception. J Obstet Gynaecol Can 2003;25:673–687. PMID: 12908020.
Foidart JM, Sulak PJ, Schellschmidt I, Zimmermann D; Yasmin Extended Regimen Study Group. The use of an oral contraceptive containing ethinylestradiol and drospirenone in an extended regimen over 126 days. Contraception 2006;73:34–40. PMID: 16371292.
Harrison-Woolrych M, Hill R. Unintended pregnancies with etonogestrel implant (Implanon): a case series from postmarketing experience in Australia. Contraception 2005;71:306–308. PMID: 15792651.
Kaunitz AM. Current concepts regarding use of DMPA. J Reprod Med 2002;47:785–789. PMID: 12380407.
Jick SS, Kay JA, Russmann S, Jick H. Risk of nonfatal venous thromboembolism in women using a contraceptive transdermal patch and oral contraceptives containing norgestimate and 35 microg of ethinyl estradiol. Contraception 2006; 73:223–228. PMID: 16472560.
Kuohung W, Borgatta L, Stubblefield P. Low-dose oral contraceptives and bone mineral density: an evidence-based analysis. Contraception 2000;61:77–82. PMID: 10802271.
Lara-Torre E. “Quick Start,” an innovative approach to the combination oral contraceptive pill in adolescents. Is it time to make the switch? J Pediatr Adolesc Gynecol 2004;17:65–67. PMID: 15010044.
Le J, Tsourounis C. Implanon: a critical review. Ann Pharmacother 2001;35:329–336. PMID: 11261531.
Marchbanks PA, McDonald JA, Wilson HG, et al. Oral contraceptives and the risk of breast cancer. N Engl J Med 2002;346: 2025–2032. PMID: 12087137.
Meckstroth KR, Darney PD. Implant contraception. Semin Reprod Med 2001;19:339–354. PMID: 11727176.
Moreno V, Bosch FX, Muñoz N, et al. Effect of oral contraceptives on risk of cervical cancer in women with human papillomavirus infection: the IARC multicentric case-control study. Lancet2002;359:1085–1092. PMID: 11943255.
Mulders TMT, Dieben TO. Use of the novel combined contraceptive vaginal ring NuvaRing for ovulation inhibition. Fertil Steril 2001;75:865–870. PMID: 11334895.
Parsey KS, Pong A. An open-label, multicenter study to evaluate Yasmin, a low-dose combination of oral contraceptive containing drospirenone, a new progestogen. Contraception 2000;6:105–111. PMID: 10802275.
Rosenberg MJ, Burnhill MS, Waugh MS, Grimes DA, Hillard PJ. Compliance and oral contraceptives: a review. Contraception 1995;52:137–141. PMID: 7587184.
Roumen FJ, Apter D, Mulders TM, Dieben TO. Efficacy, tolerability and acceptability of a novel contraceptive vaginal ring releasing etonogestrel and ethinyl oestradiol. Hum Reprod 2001;16:469–475. PMID: 11228213.
Sanchez-Guerrero J, Uribe AG, Jimenez-Santana L, et al. A trial of contraceptive methods in women with systemic lupus erythematosus. N Engl J Med 2005;353:2539–2549. PMID: 16354890.
Wagstaff AJ. Continuous-use ethinylestradiol/levonorgestrel 20microg/90microg: as an oral contraceptive. Drugs 2007;67:2473–2479. PMID: 17983260.
Webb AM. Emergency contraception. BMJ 2003;326:775–776. PMID: 12689951.
Westhoff C. Clinical practice. Emergency contraception. N Engl J Med 2003;349:1830–1835. PMID: 14602882.
INTRAUTERINE CONTRACEPTIVE DEVICES
Two types of IUDs are available in the United States: the copper T 380A device and a levonorgestrel-releasing device (Fig. 58–7). The T 380A is a T-shaped device approximately 36 mm in length and 32 mm in diameter that contains 380 mm2 of copper on its vertical and side arms. Two monofilament strings are attached to the vertical arm to ascertain placement in the uterus over the course of use. This IUD has a useful lifespan of at least 10 years. The exact mechanism of action is unknown, although current theories include spermicidal activity, interference with either normal development of ova or the fertilization of ova, and activity on the endometrium that may promote phagocytosis of sperm and that may impede sperm migration or capacitance. No data support this or other IUDs as abortifacients. The perfect use failure rate with the T 380A is 0.6 pregnancies per 100 woman-years and approximately 0.8 for typical use. In the past, IUDs were associated with an increased risk for PID around the time of insertion. However, by restricting use to mutually monogamous couples and couples currently at low risk of STIs, the absolute risk of PID in association with IUD use is almost negligible. PID appears to be associated primarily with the insertion of the device (Fig. 58–8) and not with its duration of use. Currently, with appropriately selected users, the rate of PID is approximately 1 case per 1000 insertions. Women at risk for HIV infection or who are already infected are not believed to be candidates for use of this device. Other ideal candidates are women in whom combination hormonal contraception is contraindicated. The other major risks reported in association with use of this IUD include ectopic pregnancy, spontaneous abortion, uterine perforation, and expulsion. Although 5–8% of pregnancies that occur with use of this IUD are ectopic, overall, because of the high effectiveness of this device, the absolute risk of ectopic pregnancy in users is substantially less than that experienced by nonusers of contraception. In addition, if a user becomes pregnant with the device in place, the risk of a spontaneous abortion is approximately 50%. Removing the device when the strings can be readily identified will reduce this risk by approximately 50%. If the pregnancy continues with the IUD in place, users should be apprised of an increased risk for premature rupture of the membranes and preterm delivery. Uterine perforation, which occurs at the time of insertion, has been reported at a rate of 1–2 events per 1000 insertions. This risk is minimized by performing a preinsertion pelvic examination to determine the position of the uterus and by using a tenaculum to straighten the uterine axis during insertion. Expulsions of the device are more common in the first few weeks of use, with rates of approximately 5%. Minor side effects include abnormal bleeding and cramping. Use of nonsteroidal anti-inflammatory drugs often will reduce the overall amount of flow as well as reduce cramping.
Figure 58–7. Intrauterine contraceptive devices currently available in the United States. A: The copper T 380A device; B: the levonorgestrel device.
Figure 58–8. Insertion of the ParaGard T 380A intrauterine copper contraceptive device.
The levonorgestrel-releasing intrauterine device (LNG-20 IUD) has a T-shaped frame with a reservoir on the vertical arm that releases the progestin levonorgestrel daily. Two monofilament strings are attached to the vertical arm. Blood levels of levonorgestrel among users are approximately 25% the levels seen among users of oral contraceptives containing this progestin. In contrast to the copper T 380A device, the LNG-20 IUD has a life span of 5 years in clinical trials. The primary mechanisms of action of the LNG-20 IUD are thickening the cervical mucus to impede ascent of sperm and altering the uterotubal fluid to also interfere with sperm migration. This IUD causes anovulation in approximately 10–15% of cycles and changes the characteristics of the endometrium to reduce the likelihood of implantation. Candidates for use of this IUD fit the same profile as those who would consider use of the T 380A. The perfect and typical use pregnancy rates are 0.1 pregnancies per 100 woman-years after 1 year of use, and the cumulative pregnancy rate over 5 years is 0.7 pregnancies per 100 woman-years. Approximately 50% of the pregnancies that occur are ectopic. However, as with the T 380A device, the absolute risk of ectopic pregnancy still is substantially lower than that experienced by nonusers of contraception. Because the LNG-20 IUD releases a potent progestin at the endometrial level, the bleeding pattern is substantially different from that seen with the T 380A. During the initial 3–4 months of use, some women experience irregular bleeding that may be heavy at times. However, after a few months of use, most women experience a significant decrease in menstrual flow by as much as 70%. In some studies, 20–25% of users become amenorrheic in the second year of use. In addition, dysmenorrhea tends to improve with use of this device. Because of the effectiveness of the LNG-20 IUD in reducing menstrual blood flow, it has been used for treatment of menorrhagia, a significant noncontraceptive benefit. Major risks with this IUD are similar to those noted for the copper T 380A, except that PID has not been associated with use of this device. The minor side effects of bleeding and cramping are less frequent with this device, except for irregular bleeding patterns during the first few months of use. Some women have reported headache, acne, or mastalgia, which could be related to the systemic effects of the progestin.
A not infrequent issue with IUD use is the management of missing strings. First, the patient should be encouraged to use a backup contraceptive method until she is evaluated. If the IUD strings cannot be seen even with gentle probing of the endocervical canal, one should perform a pregnancy test if indicated and consider ordering a transvaginal ultrasound to determine whether the IUD is intrauterine, intraperitoneal, or likely has undergone expulsion. If the patient is pregnant, an ectopic pregnancy must be excluded. If the IUD is determined to be intraperitoneal in location, removal usually is indicated because of likely peritoneal irritation by the device.
Backman T, Rauramo I, Huhtala S, Koskenvuo M. Pregnancy during the use of levonorgestrel intrauterine system. Am J Obstet Gynecol 2004;190:50–54. PMID: 14749634.
Rose S, Chaudhari A, Peterson CM. Mirena® (Levonorgestrel intrauterine system): a successful novel drug delivery option in contraception. Adv Drug Deliv Rev 2009;61:808–812. PMID: 19445984.
MALE CONTRACEPTION
The development of contraceptive methods for men poses a different challenge because men are continuously producing sperm and therefore are continuously fertile, unlike women who have a limited number of fertile days each month. Recent surveys have shown that men want to be more involved in contraception decisions, and women trust their male partners to take an active role in this area. The current research is focused on developing contraceptive injections, implants, or vaccines that will reduce a male’s sperm count low enough to levels unlikely to cause pregnancy, but without damaging lifetime sperm production. Tests are currently being conducted overseas, and the information in this field will continue to be expanded. Nonsurgical steroidal methods comprising various derivatives of the androgens and their receptors are in various phases of clinical trials in men. The ideal male contraceptive should be coital-independent, nonsurgical, reversible, effective, and should not alter androgen levels or libido. Several nonsteroidal molecules and vaccines are being investigated in animal models for male contraception.
Naz RK, Rowan S. Update on male contraception. Curr Opin Obstet Gynecol 2009;21:265–269. PMID: 19469045.
CONTRACEPTION OVER 40
The majority of women 40–49 years of age need an effective method of contraception because the decline in fertility with age is an insufficient protection against unwanted pregnancy. Although pregnancy is less likely after the age of 40 years, the clinical and social consequences of an unexpected pregnancy are potentially detrimental. No contraceptive method is contraindicated by advanced reproductive age alone; thus there is a need to discuss the effectiveness, risks, and noncontraceptive benefits of all family planning methods for women in this age group. A review of the literature demonstrated that decline in fecundity in the fifth decade is insufficient for contraceptive purposes; thus a family planning method is needed. Sterilization is by far the most common method in several countries. Copper IUDs and hormone intrauterine systems have similar effectiveness, with fewer than 1% failures in the first year of typical use. Special considerations in this age group include the frequency of menstrual irregularity, sexual problems, and the possibility of menopausal symptoms, all of which may respond to hormonal methods of contraception.
The ESHRE Capri Workshop Group. Female contraception over 40. Hum Reprod Update 2009;15:599–612. PMID: 19458038.
INDUCED ABORTION
Induced abortion is the deliberate termination of pregnancy in a manner that ensures that the embryo or fetus will not survive. Societal attitudes toward elective abortion have changed markedly in the past few decades. In some situations the need for abortion is accepted by most people, but political and medical attitudes regarding induced abortion have continued to lag behind changing attitudes. Certain religious objections continue to prevail, resulting in personal, medical, and political conflicts.
Approximately one-third of the world’s population lives in nations with nonrestrictive laws governing abortion. Another third live in countries with moderately restrictive abortion laws (ie, in countries where unwanted pregnancies may not be terminated as a matter of right or personal decision but only on broadly interpreted medical, psychologic, and sociologic indications). The remainder live in countries where abortion is illegal without qualification or is allowed only when the woman’s life or health would be severely threatened if the pregnancy were allowed to continue.
An estimated 1 of every 4 pregnancies in the world is terminated by induced abortion, making it perhaps the most common method of reproduction limitation. In the United States, estimates of the number of criminal abortions performed before legalization of the procedure ranged from 0.25–1.25 million per year. The number of legal abortions now being performed in the United States approximates 1 abortion per 4 live births. In 1997, there were 1.33 million induced abortions compared with 3.88 million live births.
The procedures being used in the United States for legally induced abortions during the first trimester are relatively safe. Table 58–2 shows that first-trimester legal abortions are consistently safer for the woman than if she used no birth control method and gave birth. Table 58–2 also shows that although the number of maternal deaths related to births steadily increased from 5.6 to 22.6 per 100,000 women as age increased, the age-related increase in number of deaths per 100,000 women per year from legal abortions was insignificant.
Table 58–2. Pregnancy-related deaths per 100,000 women per year in developed countries compared with deaths resulting from legal abortion as a means of contraception.
In general, the risk of death from legal abortion is lowest when it is performed at 8 menstrual weeks or sooner. During 1988–1997, the overall death rate for women obtaining legally induced abortions was 0.7 per 100,000 legal induced abortions. The risk of death increased exponentially by 38% for each additional week of gestation. Compared with women whose abortions were performed at or before 8 weeks of gestation, women whose abortions were performed in the second trimester were significantly more likely to die of abortion-related causes. The relative risk (unadjusted) of abortion-related mortality was 14.7 at 13–15 weeks of gestation (95% confidence interval [CI] 6.2, 34.7), 29.5 at 16–20 weeks (95% CI 12.9, 67.4), and 76.6 at or after 21 weeks (95% CI 32.5, 180.8). Up to 87% of deaths in women who chose to terminate their pregnancies after 8 weeks of gestation may have been avoidable if these women had accessed abortion services before 8 weeks of gestation.
Legal Aspects of Induced Abortion in the United States
The United States Supreme Court ruled in 1973 that the restrictive abortion laws in the United States were invalid, largely because these laws invaded the individual’s right to privacy, and that an abortion could not be denied to a woman in the first 3 months of pregnancy. The Court indicated that after 3 months a state may “regulate the abortion procedure in ways that are reasonably related to maternal health” and that after the fetus reaches the stage of viability (approximately 24 weeks) the states may refuse the right to terminate the pregnancy except when necessary for the preservation of the life or health of the mother. Still, much opposition is raised by various “right-to-life” groups and religious groups. In spite of this opposition, more than 1 million procedures are still performed annually in the United States, with approximately one-third performed on teenaged women. The patient must be informed regarding the nature of the procedure and its risks, including possible infertility or even continuation of pregnancy. The rights of the spouse, parents, or guardian also must be considered and permission obtained when indicated (until the individual woman’s rights are clearly established). State laws must be obeyed with special reference to residence, duration of pregnancy, indications for abortion, consent, and consultations required.
Evaluation of Patients Requesting Induced Abortion
Patients give varied reasons for requesting abortion. Because in some cases the request is made at the urging of the woman’s parents, in-laws, husband, or peers, every effort should be made to ascertain that the patient herself desires abortion for her own reasons. In addition, one should be certain that the patient knows she is free to choose from among other methods of solving the problem of unplanned pregnancy, such as adoption or single-parent rearing.
Although the majority of abortions are performed as elective procedures (ie, because of social or economic reasons as opposed to medical reasons), some women still request such services for medical or surgical indications. For example, continuation of pregnancy may pose a threat to the life of women with certain medical conditions, such as Eisenmenger’s syndrome and cystic fibrosis. Other indications are pregnancy resulting from a rape or pregnancy with a fetus affected with a major disorder, such as trisomy 13. In any event, the ultimate decision rests with the pregnant woman. Help from social agencies should be made available as necessary. A complete social history, medical history, and physical examination are required. Particular attention must be given to uterine size and position; the importance of accurate calculation of the duration of pregnancy (within 2 weeks but preferably within 1 week) cannot be overstated. With uncertainty, pelvic sonography should be used liberally. Routine laboratory tests should include pregnancy tests, urinalysis, hematocrit level, Rh typing, serologic tests for syphilis, culture for gonorrhea, and Pap smear.
Methods of Induced Abortion
Numerous methods are used to induce an abortion: suction or surgical curettage; medical abortion (performed with mifepristone alone, or with a combination of mifepristone and misoprostol or other prostaglandins), induction of labor by means of intraovular or extraovular injection of a hypertonic solution or other oxytocic agent; dilatation and evacuation; extraovular placement of devices such as catheters, bougies, or bags; hysterotomy—abdominal or vaginal; hysterectomy—abdominal or vaginal; and menstrual regulation.
The method of abortion used is determined primarily by the duration of pregnancy, with consideration for the patient’s health, the experience of the physician, and the available physical facilities. The risk of repeat abortion is associated with various sociodemographic characteristics, but apparently the method of abortion used is not a risk factor for repeat termination of pregnancy.
Suction curettage on an outpatient basis performed under local or light general anesthesia can be accomplished with a high degree of safety. The safety of outpatient abortion and the shortage of hospital beds have led to the development of single-function, “freestanding” abortion clinics. In addition to providing more efficient counseling and social services, these clinics have effectively reduced the cost of abortion. Many hospitals have “short-stay units,” which match the efficiency of outpatient clinics but also offer the backup facilities of the general hospital.
A. Suction Curettage
Suction curettage is the safest and most effective method for terminating pregnancies of 12 weeks’ duration or less. This technique has gained rapid worldwide acceptance, and more than 90% of induced abortions in the United States are now performed by this method. The procedure involves dilatation of the cervix by instruments or by hydrophilic Laminaria tent (see Induction of Labor by Intra-Amniotic Instillation), followed by insertion of a suction cannula of the appropriate diameter into the uterine cavity (Fig. 58–9). Most procedures are performed using a paracervical block with local anesthesia with or without additional medication for sedation. Standard negative pressures used range from 30–50 mm Hg. Many physicians follow aspiration with light instrumental curettage of the uterine cavity.
Figure 58–9. Suction method for induced abortion.
The advantages of suction over surgical curettage are that suction curettage empties the uterus more rapidly, minimizes blood loss, and reduces the likelihood of perforation of the uterus. However, failure to recognize perforation of the uterus with a cannula may result in serious damage to other organs. Knowledge of the size and position of the uterus and the volume of the contents is mandatory for safe suction curettage. Moreover, extreme care and slow minimal dilatation of the cervix, with special consideration for the integrity of the internal os, should prevent injury to the cervix or uterus. Attention to the decrease in uterine size that occurs with rapid evacuation helps to avoid uterine injury.
When performed in early pregnancy by properly trained physicians, suction curettage should be associated with a very low failure rate. The complication rate should be <1% for infection, approximately 2% for excessive bleeding, and <1% for uterine perforation. The risk of major complications, such as persistent fever, hemorrhage requiring transfusion, and unintended major surgery, ranges between 0.2 and 0.6% and is proportional to pregnancy duration. The incidence of mortality for suction curettage is approximately 1 in 100,000 patients.
B. Surgical Curettage
Surgical (“sharp”) curettage has been used for first-trimester abortion in the absence of suction curettage equipment. This procedure is performed as a standard dilatation and curettage, such as for the diagnosis of abnormal uterine bleeding or for the removal of endometrial polyps. The blood loss, duration of surgery, and likelihood of damage to the cervix or uterus are greatly increased when surgical curettage is used. In addition, the risk of uterine synechiae or Asherman’s syndrome is increased with this approach. Accordingly, suction curettage is generally preferred over sharp curettage for first-trimester termination procedures.
Bartz D, Goldberg A. Medication abortion. Clin Obstet Gynecol 2009;52:140–150. PMID: 19407520.
Bartlett LA, Berg CJ, Shulman HB, et al. Risk factors for legal induced abortion-related mortality in the United States. Obstet Gynecol 2004;103:729–737. PMID: 15051566.
Creinin MD. Randomized comparison of efficacy, acceptability and cost of medical versus surgical abortion. Contraception 2000;62:117–124. PMID: 11124358.
Grimes DA, Creinin MD. Induced abortion: an overview for internists. Ann Intern Med 2004;140:620–626. PMID: 15096333.
Haimov-Kochman R, Arbel R, Sciaky-Tamir Y, Brzezinski A, Laufer N, Yagel S. Risk factors for unsuccessful medical abortion with mifepristone and misoprostol. Acta Obstet Gynecol Scand 2007;86:462–466. PMID: 17486469.
Hubacher D, Grimes DA. Noncontraceptive health benefits of intrauterine devices: a systematic review. Obstet Gynecol Survey 2002;57:120–128. PMID: 11832788.
Niinimäki M, Pouta A, Bloigu A, et al. Frequency and risk factors for repeat abortions after surgical compared with medical termination of pregnancy. Obstet Gynecol 2009;113:845–852. PMID: 19305329.
Vargas J, Diedrich J. Second-trimester induction of labor. Clin Obstet Gynecol 2009;52:188–197. PMID: 19407525.
C. Medical Abortion
Medical methods for pregnancy termination in early gestation offer women an alternative to surgical evacuation and have the potential to improve access globally to safe abortion. Several drug regimens are used with varying efficacy, including mifepristone plus misoprostol, misoprostol alone, and methotrexate plus misoprostol. Where available, a mifepris-tone plus misoprostol regimen is most frequently used and is highly effective for early abortion. Overall, women who choose medical abortion report high levels of satisfaction.
Women with first-trimester pregnancies <49 days from their first day of the last menstrual period may be eligible for medical abortion. An alternative method of medical abortion consists of the administration of an oral antiprogestin (RU-486 [mifepristone]) followed by oral misoprostol 48 hours later. The reported success rate of this method is >90%, provided the protocol is started before 7 weeks from the last menstrual period. Complications include cramping, bleeding due to incomplete abortion, and failure to evacuate the uterus necessitating completion by suction curettage. With one of the more common protocols, 50 mg methotrexate is administered orally, followed by 800 mg misoprostol per vagina (by the patient at home) 3–7 days later using the same tablets as those used for oral dosing. The patient is seen at least 24 hours after the misoprostol administration; a vaginal ultrasound is performed to determine whether there has been passage of the gestational sac. If abortion has not occurred, the misoprostol dose is repeated. The patient is then followed up in 4 weeks; if abortion has not occurred by this time, a suction curettage is typically performed. If fetal cardiac activity is noted on ultrasound, office follow-up is more frequent. Efficacy with this method is up to 98% for pregnancies up to 49 days’ gestation; complete abortion rates are inversely proportional to duration of gestation. Nausea is the most frequently reported side effect. Older age, previous spontaneous abortions, and multigravidity are apparently independent risk factors for unsuccessful medical abortion.
Contraindications include active liver disease, active renal disease, severe anemia, acute inflammatory bowel disease and coagulopathy, or anticoagulant therapy.
D. Induction of Labor by Intra-Amniotic Instillation
The Japanese developed this technique for induced abortion after the first trimester. Currently, the technique is used almost exclusively for initiating midtrimester abortion. The original procedure consisted of amniocentesis, aspiration of as much fluid as possible, and instillation into the amniotic sac of 200 mL hypertonic (20%) sodium chloride solution. In most (80–90%) cases, spontaneous labor and expulsion of the fetus and placenta occur within 48 hours. This technique has been modified, primarily to reduce the injection– abortion interval, and as a result of the development of other agents that initiate labor when instilled intra-amniotically.
Because of the problems associated with hypertonic sodium chloride, many clinicians have used intra-amniotic hyperosmolar (59.7%) urea, usually with oxytocin or prostaglandin or intra-amniotic prostaglandin alone. These approaches result in injection–abortion intervals of 16–17 hours for urea and 19–22 hours for prostaglandin. The urea is instilled in a fashion similar to that described for hypertonic sodium chloride. The prostaglandin, most frequently prostaglandin F2a (PGF2a), usually is instilled as a single dose of 40–50 mg or as 2 doses of 25 mg instilled 6 hours apart. When oxytocin is used to augment these agents, doses as high as 332 mU/min are required to produce uterine contractions because of the relative insensitivity of the myometrium to oxytocin at this stage of pregnancy. To avoid water intoxication, the oxytocin is made up in highly concentrated solutions and given at slow rates.
It is advantageous to soften the unripe cervix with Laminaria tents placed in the cervix a few hours before amniocentesis is performed. Such an approach markedly reduces the risk of cervical injury.
Midtrimester abortion induced by this method must be accomplished with scrupulous aseptic surgical technique, and the patient must be monitored until the fetus and placenta are delivered and postabortion bleeding is under control. The complication rate is high—up to 20% in some institutions—and the mortality rate is comparable to that of term parturition. Fortunately, because first-trimester abortion is now more readily available, more women are consulting their physicians early and thus availing themselves of the much safer suction curettage.
Several types of complications are associated with the use of instillation agents. Retained placenta is the most common problem; rates ranging from 13 to 46% have been reported. The placenta usually can be removed without difficulty using ring forceps and large curettes with the patient under local anesthesia. Hemorrhage may be caused by retained products or atony; coagulopathy is seen in up to 1% of patients in whom hypertonic sodium chloride is used. Infection can occur but is reduced significantly by use of prophylactic antibiotics in high-risk situations (eg, in patients with early ruptured membranes and during injection–abortion intervals >24 hours). Cervical laceration can occur but is reduced by the use of Laminaria tents. Hypernatremia can occur with the use of hypertonic sodium chloride if the drug is absorbed rapidly by the placental bed or if it is given intravascularly by mistake.
Failure of labor to expel the products of conception necessitates either a repetition of the procedure if the membranes are still intact or oxytocin stimulation, usually by intravenous injection or use of the dilatation and evacuation technique.
Emotional stress is an important factor for many women because they are awake at the time of the expulsion of the fetus and the fetus is well formed. (The emotional stress is also a factor for hospital personnel—a problem impossible to avoid.)
E. Induction of Labor with Vaginal Prostaglandins
Second-trimester abortions are most commonly performed in the United States via dilation and evacuation; however, there are instances in which the use of systemic abortifacients is necessary. Lack of trained staff to perform late abortion procedures, fetal anomalies, and patient preference are important considerations when selecting the method of termination. Second-trimester abortions with misoprostol-only protocols require higher doses, side effects are more common, and the time to complete the abortion is longer in comparison with mifepristone-misoprostol combinations. Feticidal agents are recommended to avoid transient fetal survival. Prostaglandin E2 given intravaginally can be used to induce midtrimester abortion. Vaginal suppositories containing 20 mg are used every 3–4 hours until abortion occurs; the presence or absence of labor determines whether the prostaglandin E2 should be stopped. Misoprostol, a synthetic prostaglandin E1 analogue, is also used. Treatment–abortion intervals, rates of incomplete abortion, and complications are similar to those described for instillation agents. The major disadvantages are significant gastrointestinal side effects, a higher incidence of live abortion, and a more frequent occurrence of fever.
F. Dilatation & Evacuation
This technique for inducing midtrimester abortion is essentially a modification of suction curettage. Because fetal parts are larger at this stage of pregnancy, most operators use serial placement of Laminariatents to effect cervical dilatation with less likelihood of injury. Larger suction cannulas and specially designed forceps are used to extract tissue. In most instances, the operation can be performed in the outpatient setting using paracervical block anesthesia and intravenous sedation on patients with pregnancies up to 18 weeks’ gestation. Complications include hemorrhage (usually due to atony or laceration), perforation, and rarely infection. Retained tissue is uncommon, especially when tissue is carefully inspected for completion at the end of each procedure. Compared with instillation techniques or vaginal prostaglandin, the overall incidence of complications (in pregnancies up to 18 weeks’ gestation) is less with dilatation and evacuation. In addition, most patients prefer the technique because it is an outpatient procedure and the woman does not undergo labor.
G. Hysterotomy & Hysterectomy
The use of hysterotomy and hysterectomy is currently reserved for special circumstances such as the failure to complete a midtrimester abortion due to cervical stenosis or the management of other complications. Both approaches, compared with other techniques discussed, have unacceptably high rates of morbidity and mortality, and neither should be used as a primary method.
H. Menstrual Regulation
Menstrual regulation consists of aspiration of the endometrium within 14 days after a missed menstrual cycle or within 42 days after the beginning of the last menstrual period by means of a small cannula attached to a source of low-pressure suction, such as a syringe or other suction machine. This is a simple and safe procedure that can be readily performed in the office or outpatient clinic, usually without any anesthetic, although paracervical block can be used if necessary. Menstrual regulation was used extensively in the 1970s and 1980s before reliable, inexpensive, and sensitive urine pregnancy tests became available. It offered a safe early approach to pregnancy termination; however, approximately 40% of women were not pregnant at the time of the procedure. With the advent of urine pregnancy tests that have the ability to document pregnancy even before a missed menstrual period, standard first-trimester suction curettage probably is more widely used. Complications are similar to those described for suction curettage except that persistent pregnancy is more common, particularly when very early menstrual regulation procedures are performed.
I. RU-486
RU-486 (mifepristone) is a synthetic drug, developed by French pharmacologists, that acts at least partially as an anti-progestational agent. When given orally in conjunction with a prostaglandin such as misoprostol, it effects first-trimester abortion. Complications include failure to terminate a pregnancy, incomplete abortion, and significant uterine cramping.
Follow-Up of Patients After Induced Abortion
Follow-up care after all procedures must be ensured. After abortion by all methods, human Rho (D) immune globulin (RhoGAM) should be administered promptly if the patient is Rh-negative, unless the male partner is known to be Rh-negative. The patient should take her temperature several times daily and report fever or unusual bleeding at once. She should avoid intercourse or the use of tampons or douches for at least 2 weeks. The physician should discuss with the patient the possibility that emotional depression, similar to that after term pregnancy and delivery, may occur after induced abortion. Follow-up care should include pelvic examination to rule out endometritis and parametritis, salpingitis, failure of involution, or continued uterine growth. Finally, effective contraception should be made available according to the patient’s needs and desires.
Long-Term Sequelae of Induced Abortion
Many studies during the past 2 decades have examined the possible long-term sequelae of elective induced abortion. Most of the attention has focused on subsequent reproductive function; unfortunately, many of the studies had inherent biases and serious methodologic flaws. Despite these problems, enough information is available to provide relative estimates of potential risks. Data from some studies suggest that midtrimester pregnancy loss is more common in women who have undergone 2 or more induced or spontaneous abortions. However, women who have undergone 1 procedure have essentially the same risk as women who have experienced a single term pregnancy. Regarding low birthweight, only women who have undergone a first-trimester procedure by sharp curettage under general anesthesia appear to have increased risks. The reason for this association might be related to the method of dilatation used. Finally, studies that have examined both ectopic pregnancy and infertility have failed to show any consistent association between these adverse events and prior induced abortion.
Burkman RT. Clinical pearls: factors affecting reported contraceptive efficacy rates in clinical studies. Int J Fertil Womens Med 2002;47:153–161. PMID: 12199411.
Chandra A, Martinez GM, Mosher WD, Abma JC, Jones J. Fertility, family planning, and reproductive health of US women: data from the 2002 National Survey of Family Growth. National Center for Health Statistics. Vital Health Stat 2005;23:1–160. PMID: 16532609.
Dailard C, Gold RB. Fulfilling the Promise: Public Policy and U.S. Family Planning Clinics. New York: The Alan Guttmacher Institute; 2002.
Kubba A, Guillebaud J, Anderson RA, MacGregor EA. Contraception. Lancet 2000;356:1913–1919. PMID: 11130398.
Ventura MA, Abma JC, Mosher WD, Henshaw SK. Estimated pregnancy rates for the United States, 1990–2005: an update by Stephanie J. Centers for Disease Control and Prevention National Center for Health Statistics National Vital Statistics System. Natl Vital Stat Rep 2009;58:1-14. PMID: 20121003.