Fertility Control: I. Medical Aspects
The ability of individuals to regulate their own childbearing represents one of the great medical advances of the twentieth century. As a result of demographic trends, which indicate an earlier onset of sexual activity and smaller family size, a woman may spend as long as thirty-five years purposefully avoiding pregnancy. An array of contraceptive methods is necessary to provide individuals with options that are most appropriate to their lifestyle, motivation, desire for effectiveness and convenience, and acceptance of medical risk. Two fundamental trends have affected contraceptive practice since 1960: the development of safe, continuous, and highly effective hormonal contraception, and more recently, an increased awareness of the role of barrier contraceptives for the dual purposes of pregnancy prevention and protection against sexually transmitted infections.
Currently available contraceptive methods include permanent methods that cause sterility—such as vasectomy in men and tubal occlusion in women—and reversible methods. Reversible methods include oral contraceptives (OCs); subdermal implants (Norplant®); progestin injections (depotmedroxyprogesterone acetate; DMPA; Depo-Provera®); intrauterine devices (IUDs); barrier methods (male and female condoms, diaphragm, cervical cap, and spermicidal products); and "natural" methods such as celibacy, periodic abstinence (natural family-planning and fertility-awareness methods), and withdrawal.
It is unreasonable to assume that there is an ideal contraceptive method for each couple; more commonly, couples alternate among various methods over time. A number of general considerations can help to guide an individual (or couple) in the selection of an appropriate contraceptive method.
FREQUENCY OF SEXUAL INTERCOURSE. Couples who have frequent intercourse (arbitrarily defined as more than two to three episodes of intercourse per week) should consider the more continuous, non-coitusrelated methods of contraception: OCs, IUDs, implants, injectables, or if childbearing is completed, permanent sterilization. For less sexually active couples (those who have intercourse less than once per week), an episodic method, such as a barrier contraceptive, would provide protection without exposure to method-related risks at other times.
NUMBER OF SEXUAL PARTNERS. Individuals who have multiple sexual partners, or whose partners have other partners, should be advised to consider one or more barrier methods, with the dual purposes of protection against sexually transmitted infections (STIs) and prevention of pregnancy. For couples who desire an optimal degree of pregnancy prevention, a combined approach of a barrier method plus a highly effective contraceptive will compensate for the relatively high pregnancy rate associated with barrier methods. Additionally, women in this category should not wear an IUD, as the risk of pelvic inflammatory disease (PID) and tubal infertility in IUD wearers is increased significantly in women with multiple sexual partners. For couples who are involved in a mutually monogamous relationship, no method of reversible contraception, including the IUD, increases the risk of PID or tubal infertility.
USER ACCEPTABILITY. Personal attitudes regarding the acceptability of certain methods may influence the success of use. These include religious beliefs, which may preclude the use of "mechanical" and hormonal contraceptives; tolerance of "nuisance" side effects, such as breast changes and vaginal bleeding; willingness to touch the genitals (of self or partner); and aesthetic concerns, such as tolerance of the "messiness" of spermicidal creams and jellies.
MOTIVATION AND SELF-DISCIPLINE. The degree of motivation to avoid pregnancy has a strong impact upon the successful use of contraceptives. Women who contracept to delay pregnancy have a higher failure rate than those who are intent on pregnancy prevention. Self-discipline also must be assessed, as women who are highly motivated may do well with intercourse-related (barrier) methods, while individuals who are poorly motivated should choose continuous non-intercourse-related methods such as OCs, IUDs, implantable or injectable methods, or sterilization.
ACCESS TO MEDICAL CARE. Because of the risk of medical complications, certain methods should be used only on the condition of reasonable access to medical care. This concern centers mainly on IUDs and to a lesser extent, hormonal methods. Users of barrier methods, natural methods, and those who have been successfully surgically sterilized have a negligible risk of life-threatening method-related complications.
EFFECTIVENESS. Desire for high effectiveness versus willingness to accept a degree of risk of failure is a primary concern for many contraceptors. Those who insist upon a high degree of efficacy are best advised to use a combination OC (discussed below), an IUD, an implantable or injectable method, or sterilization. Alternatively, for individuals who will accept a higher method failure rate, coupled with an understanding that such failures will result in a choice between delivery and abortion, less effective methods, including barriers and natural methods, may be used.
SAFETY. Medical safety is a major concern for most contraceptors, and concerns regarding health risks are a major reason for discontinuation of use. Paradoxically, adolescents are more likely to avoid or prematurely discontinue contraceptives for fear of adverse health effects, yet they comprise the age group least likely to experience them. The risks associated with contraceptive use are dependent on the following four variables, with an example of each:
- Age. The risk of arterial complications (adverse effect on the heart and blood vessels, e.g., heart attack) of OCs is age-related; this risk is greatly compounded by cigarette smoking.
- Underlying medical conditions. Women with underlying cardiovascular risk factors (e.g., hypertension, glucose intolerance, hyperlipidemia, cigarette use) are more likely to experience myocardial infarction (heart attack) while using OCs.
- Sexual behaviors. A pattern of multiple sexual partners increases the risk of STIs. In particular, IUD wearers would have a greater risk of PID resulting in primary tubal infertility (fallopian tubes blocked by scar tissue).
- Method-specific risk. Complications are intrinsic to the method, regardless of age, health, and sexual behaviors. Examples include the risk of hepatic adenomas (liver tumors that are noncancerous but that may hemorrhage) in OC users; and pelvic actinomycosis (infection) in long-term IUD users.
A key component of contraceptive efficacy and safety resides in the quality and clarity of instruction and counseling given to the user. Initial instruction should include a description of the methods of contraception currently available, their relative effectiveness, the advantages and disadvantages of each method, and, if appropriate, a comparison of short- and long-term costs. Once a method has been chosen, instruction should center on method-specific advice, such as information regarding method use and danger signals that should be reported to the provider. If the individual will be learning the use of a relatively complex method, or one with an increased likelihood of side effects, it is prudent to provide a simple backup contraceptive method, such as condoms, should the user decide to abandon the initial method. Method-specific counseling should be supplemented with a written fact sheet or other instructional material at a reading and comprehension level appropriate to the individual. Finally, the user should be encouraged to telephone or visit the office of the provider, as necessary, for further advice or modification of contraceptive use.
The oral contraceptive (OC) is the method of reversible contraception used most widely in the United States. Two types are available: combination OCs, which contain fixed (monophasic) or variable (multiphasic) doses of synthetic estrogen and progestin, and progestin-only pills (POPs, mini pills). OCs primarily prevent pregnancy by preventing ovulation (release of an egg from the ovary). The estrogen and progestin in the pill exert negative feedback on the hypothalamus (the part of the brain that controls hormone production by the pituitary gland) to suppress the release of the hormone GnRH, which in turn decreases secretion of the pituitary hormones LH and FSH, preventing ovulation. OCs also thicken cervical mucus, which promotes an environment hostile to sperm and alters the endometrium (the lining of the uterus), so that implantation of an embryo is unlikely to occur even if an egg "breaks through" (is released) and is then fertilized. The failure rate of combined oral contraceptives when used correctly and consistently is 0.1 pregnancies per one hundred women per year. In typical use, the failure rate is three pregnancies per one hundred women per year.
Research continues on a male birth control pill. The initial study, announced in 1996, showed that the pill lowered sperm counts significantly with few, if any, side effects. This contraceptive is composed of a progestin and testostrone.
BENEFICIAL EFFECTS OF OCS. Prevention of pregnancy: When used correctly, OCs are highly effective in preventing pregnancy. This includes ectopic pregnancies (those that implant outside the uterus), thus preventing an important cause of maternal morbidity and mortality. There is no increase in the rate of spontaneous abortion or fetal anomalies in former users of OCs, and no long-term reduction in fertility has been demonstrated.
Prevention of acute salpingitis (also called pelvic inflammatory disease, or PID): Even when controlled for sexual behavior and for the coincident use of barrier contraceptives, studies have shown that OC users have a decreased risk of acute salpingitis. It also appears that cases of salpingitis are less severe in OC users overall when compared to controls. Paradoxically, OC users seem to have a higher rate of chlamydial endocervicitis (an STI, with inflammation of the cervix, which may or may not progress to PID).
Prevention of genital tract cancers: Data from the Centers for Disease Control and Prevention's (CDCP) Cancer and Steroid Hormone (CASH) study show a 50 percent reduction in risk for the development of both endometrial and ovarian cancer. Past use of OCs appears to bestow this protective effect for as long as fifteen years after the user has discontinued OC use. The relationship of OCs and cervical dysplasia (abnormal cells of the cervix that, if not monitored, sometimes progress to cancer) and carcinoma is somewhat more complex because of confounding biases, but overall, OC use neither causes nor protects against cervical neoplasia (abnormal tissue formation).
Relief of menstrual symptoms: OCs provide excellent therapy for primary dysmenorrhea ("normal" painful or difficult menstruation that is not related to a disease) because they suppress the endometrium (the lining of the uterus). Consequently, the endometrium does not produce as much prostaglandin, the substance that produces cramping of the uterus. There is a more variable effect on premenstrual syndrome, in that while many women have a decrease in symptoms, others have no change, and a small percentage have worsening symptoms. Because of shorter and lighter menses, the incidence of iron deficiency anemia is reduced by 65 percent. There is also a reduced risk of toxic shock syndrome.
Reduced risk of benign breast disease: OC users have a significant reduction in the incidence of benign (noncancerous) breast conditions, including fibroadenoma and fibrocystic change.
Prevention and treatment of functional ovarian cysts: As a result of the pharmacologic suppression of GnRH release and consequent blunting of pituitary gonadotrophin release, women who use OCs are less likely to develop functional ovarian cysts than women who do not use hormonal contraception. This effect appears to be doserelated, and users of low-dose OC products have less protection than those using stronger formulations. If OCs are given in an attempt to suppress an existing ovarian cyst, it is necessary to utilize a relatively strong product (e.g., Ovral) in order to achieve an effective degree of hypothalamic/pituitary suppression.
Other beneficial effects: For reasons that are unclear, OC users also have a lower incidence of rheumatoid arthritis and peptic ulcer disease.
ADVERSE EFFECTS OF OCS. The most common OC-related side effects are relatively minor. However, the patient may perceive them as major, and this may result in OC discontinuation and subsequent pregnancy. Effective management of minor or "nuisance" OC side effects consists mainly of patient education, and occasionally, medical intervention. Side effects include nausea, weight gain, spotting or breakthrough bleeding between menstrual periods, failure to have a menstrual period during the seven days off OCs, new onset or exacerbation of headaches, and chloasma (darkening of facial skin). Complications, while rare on lowdose combined oral contraceptives, can be serious.
Vascular complications: While initial studies indicated a direct relationship between estrogen dose and an increased risk of deep vein thrombosis (clotting) and pulmonary thromboembolism, more recent studies with low-estrogendose products have demonstrated only a minimally elevated attributable risk of these complications. For this reason, OC products containing thirty-five mcg of estrogen or less should be used routinely. In early studies of unselected women using relatively high-dose products, OC users also demonstrated an increased risk of myocardial infarction and stroke in comparison to controls. As a result of exclusion of women with major cardiovascular risk factors and a progressive trend toward the use of lower-dose products, OC users as a group no longer have an elevated attributable risk of OC-induced morbidity or mortality from arterial disease.
Hypertension: The estrogen and progestin components of OCs act in concert to occasionally cause the development of blood-pressure elevation in a small number of OC users. Hypertension is reversible with discontinuation of OCs.
Carbohydrate intolerance: The progestin component of OCs is known to cause peripheral glucose resistance and consequent elevation of insulin levels. In most cases, these effects are minor and are not clinically significant. If a diabetic woman is started on OCs, frequent blood glucose monitoring is necessary initially, as insulin requirements may change. OCs should not be given to diabetics who have clinically manifested vascular or kidney disease or to those with such cardiovascular risk factors as smoking, hypertension, hyperlipidemia (elevated fatty substances in the blood), or age over forty.
Breast cancer: The relationship between OC use and breast cancer has been studied extensively since the mid-1970s. In aggregate, the studies show that the relative risk of breast cancer in a present or former OC user is 1.0, implying neither protection nor increased risk. This relationship was present with a number of subgroups, including women who had initiated OCs at an early age, those who used OCs for longer than ten years, women with a history of benign breast disease, and those with a positive family history. However, a number of studies performed in the early 1980s demonstrated a possible association between OC use and breast cancer in other subgroups. The only thread of consistency in these studies was to show a small increase in the risk of breast cancer for recent OC users who developed breast cancer at an age younger than thirty-five. In that there seems to be a small reduction in breast cancers in past OC users older than thirty-five, it has been hypothesized that OCs, like pregnancy and exposure to other hormonal contraceptives, may be a weak breast cancer promoter, and that OCs may hasten the growth of a tumor already in existence.
On October 29, 1992, the U.S. Food and Drug Administration (FDA) approved contraceptive labeling for depotmedroxyprogesterone (DMPA); commonly known by its trade name, Depo-Provera. This culminated a twenty-year effort to make a long-acting injectable contraceptive available to American women. Based upon the findings of extensive clinical research done outside the United States over a decade, the FDA determined that while some concerns remained, DMPA was considered to be as safe as other hormonal contraceptives already on the market.
DMPA's mechanism of action is quite similar to that of all other hormonal methods of contraception: inhibition of ovulation; thickening of cervical mucus, which makes sperm penetration through the cervical mucus more difficult; and induction of endometrial atrophy, which prevents implantation in the highly unlikely event of fertilization. The chemical structure of DMPA is much closer to that of natural progesterone than that of the 19-nortestosterone progestins used in oral contraceptives and Norplant. This may account for the fact that DMPA users have little, if any, change in a number of metabolic parameters over time. In particular, there is no change in clotting factors, globulin levels, or glucose metabolism in DMPA users when compared to pretreatment levels. The slight decrease in total cholesterol levels seen in DMPA users is the result of a minor drop in high-density lipoprotein, the "good" cholesterol, although neither change is clinically significant. Interestingly, DMPA positively affects the central nervous system, causing the seizure threshold to increase, thus making seizures less likely in women with seizure disorders (e.g., epilepsy). Estrogen levels in DMPA users remain at early follicular phase levels, and while other menopausal symptoms do not occur, there is a possibility that some DMPA users may lose a small amount of bone mass over time.
With DMPA there are 0.3 failures per one hundred women during the first year of typical use. This high efficacy is due both to DMPA's efficiency in inhibiting ovulation and the fact that it is a relatively "user friendly" method of contraception. The long interval between injections, a two-week grace period for injections given beyond twelve weeks, and the absence of need for any user or partner intervention at intercourse all contribute to DMPA's high effectiveness.
DMPA is given as a deep intramuscular injection into the deltoid (upper arm) or buttocks every twelve weeks. Since administration most optimally is provided with a 11/2 inch needle, most DMPA users, particularly thin women, will prefer the buttocks site. The initial injection of 150 mg of DMPA must be given within the first five days after the onset of menses, unless the woman has effectively been using the pill or has an IUD, in which case the first injection can be given any time during the month. Subsequent 150-mg injections are given at twelve-week intervals, although pregnancy is highly unlikely during the following two-week grace period. If fourteen weeks or more have elapsed since the last DMPA injection, a negative highly sensitive urine pregnancy test must be documented before the next injection is given.
The ideal candidate for DMPA is a woman who is seeking continuous contraception; wants long-term birth spacing; desires a method that is neither coitus-dependent nor requires daily motivation; or who cannot use, or chooses not to use, a barrier method, an IUD, or an estrogencontaining method. It may be particularly appropriate for women who cannot use OCs because of a history of thrombophlebitis, hypertension, heavy smoking, or other cardiovascular risk factors. Women with sickle-cell anemia or seizure disorders actually may experience an improvement in their medical condition. DMPA is an excellent method for postpartum and post-abortal women and can be initiated immediately after completion of the pregnancy. Postpartum women who are lactating (nursing) should not be given DMPA until lactation has been established, usually one to two weeks after delivery. Women who desire a high degree of confidentiality in contraceptive use are attracted to DMPA because it does not require the personal possession of medications or devices, nor does it leave marks of administration or current use.
DMPA has few contraindications: active thrombophlebitis; undiagnosed abnormal genital bleeding; known or suspected pregnancy; active liver disease; a history of benign or malignant liver tumors; known or suspected carcinoma of the breast; and sensitivity (allergy) to the medication. Special conditions requiring more detailed medical evaluation and follow-up include a history of heart attack or stroke; diabetes mellitus; current migraine headaches; a history of severe endogenous depression; and chronic hypertension.
Menstrual changes are universal in women using DMPA and include episodes of irregular bleeding and spotting (lasting seven days or more during the first months of use) and amenorrhea (no menses). Sixty percent of women using DMPA for one year report amenorrhea, and the percentage increases with progressively longer use. Menstrual changes are the most frequent cause for dissatisfaction and discontinuation among women using DMPA, and appropriate patient education and selection and supportive follow-up measures can markedly reduce patient discontent. Medical intervention for irregular or heavy bleeding rarely is necessary, and anemia is uncommon. While counseling and reassurance are initial measures, medical therapy consisting of low-dose oral estrogen for one to three weeks may give temporary respite from bleeding. Women persistently dissatisfied may be better served by discontinuing this method and seeking alternative types of contraception rather than by repetitive medical or surgical intervention. In cases of heavy vaginal bleeding, gynecologic evaluation to rule out such unrelated conditions as vaginitis, cervicitis, or cervical lesions should be performed.
Another group of side effects that occur fairly frequently among DMPA users are pregnancy symptoms such as nausea, breast tenderness, abdominal bloating, and tiredness. While these symptoms are prevalent in the first few months of DMPA use, persistence is uncommon and they rarely are cause for discontinuation.
Weight gain occurs in two-thirds of DMPA users owing to the drug's anabolic effect and its resultant impact on appetite. On average, DMPA users gain four pounds per year for each of the first two years of use. Women concerned or dissatisfied with weight gain should be counseled that it may be controlled with adequate exercise and moderate dietary restriction. Many women notice weight stabilization or improvement with time. If these measures fail and weight gain becomes problematic, DMPA discontinuation may become necessary.
Headache is a relatively common complaint in DMPA users, although not all headaches are necessarily related to the hormone in the drug. If the headaches are mild and without neurologic changes, treatment may be attempted with oral analgesics.
After a 150-mg injection of DMPA, the mean interval until return of ovulation is four to six months. Conception usually is delayed in former DMPA users when compared with women discontinuing oral contraceptives or IUDs. The median time to pregnancy following the last injection is nine to ten months, and studies have shown that almost 70 percent of former DMPA users conceive within the first twelve months following discontinuation, and over 90 percent conceive by twenty-four months, a rate comparable to that of oral contraceptive users. Nulliparous women (those who have never given birth to a child) and those using DMPA for many years experience the same return of fertility as other women studied.
Recent medical studies have addressed other safety issues regarding DMPA use. A large study conducted by the World Health Organization (WHO) showed that in aggregate, there is no overall increased risk of breast, cervical, or ovarian cancers in users of DMPA. DMPA users have a reduction in endometrial cancer for as long as ten years after discontinuation of the method. While there was evidence of a weak association between DMPA use and breast cancer in the subgroup of women under thirty-five who had used the drug within the previous four years, most experts feel that this represents a very weak promoter effect at a level similar to OC use. A single study showed a 7 percent reduction in bone density in premenopausal DMPA users compared to controls, but it is not clear whether this is a true biologic effect caused by low estrogen levels or due to selection bias. Until more work is done in this area, some believe that it is prudent to screen potential DMPA users for osteoporosis risk factors and to provide additional counseling or evaluation for those with multiple risk factors.
Norplant is a sustained-release contraceptive system that acts continuously for five years. It consists of six silicone rubber capsules, each the length and diameter of a matchstick, which are surgically implanted under the skin of the upper arm. The synthetic progestin Levonorgestrel, a hormone found in many oral contraceptives, is slowly released into the bloodstream, resulting in a constant hormone level. The contraceptive effect of Norplant is due primarily to inhibition of ovulation, although secondary mechanisms include thickening of cervical mucus, and formation of an atrophic endometrium. Although 20 percent of Norplant users ovulate in year one and up to 50 percent ovulate by year five of use, studies suggest that when ovulation does occur, it is defective and the ovum is not subject to fertilization. The cumulative pregnancy rate of Norplant users is 3.8 pregnancies per one hundred women over five years; the first-year failure rate is only 0.09 per hundred women per year. Ectopic (tubal) pregnancies are reduced by two-thirds in comparison to noncontracepting women, although should Norplant fail, there is a greater conditional probability (proportionate risk) that the pregnancy will be located in the fallopian tube rather than in the uterus.
Studies that have evaluated the metabolic effects of Norplant have found minimal impact. There is no effect on cholesterol or lipoprotein metabolism, glucose metabolism, or propensity to blood clotting. Norplant is an appropriate method of contraception for women who desire long-term contraception, who have completed childbearing but do not desire permanent sterilization and have had problems with other methods of contraception (including combined OCs), and for postpartum women, whether nursing or not.
The technique of insertion of Norplant involves anesthetizing the skin with local anesthetic and creation of a four-millimeter incision, followed by placement of a twelvegauge trochar to insert the capsules in a fan-shaped pattern. The procedure takes less than ten minutes and is well tolerated by most women. The method should be inserted within five days of the onset of the menses and provides a contraceptive effect within twenty-four hours. More problematic is Norplant removal, which requires substantially more skill and takes between fifteen and forty minutes. The ease of removal is related to a number of factors, including the correctness of the initial Norplant insertion, the amount of fibrous tissue that has developed around the capsules, and the skill of the clinician.
The most prevalent adverse effect of Norplant is the unpredictability and irregularity of menstrual cycles, especially in the first year of use. Cycles may be shorter or longer than usual and associated with more or less bleeding; there may be bleeding between cycles, or no bleeding at all. Although there is no cure for irregular bleeding patterns, short-term palliation of the problem can be achieved by the use of low-dose oral estrogen therapy (e.g., ethinyl estradiol 20 mcg orally per day for two to three weeks). Other side effects include mild weight gain, headaches, hair loss, and new onset or exacerbation of depression.
Intrauterine Devices (IUDs)
Although the IUD is used by only 1 to 2 percent of contracepting women in the United States, it is one of the most widely used methods worldwide. A popular method in the United States in the 1970s, IUD use dropped precipitously as a result of the high rate of pelvic infection and consequent tubal infertility experienced by women who used the Dalkon Shield IUD, which was removed from the market for this reason. Mainly because of business concerns related to the risk of product liability suits, manufacturers of most other IUDs voluntarily withdrew their devices over the next decade. The two IUDs currently available in the United States include a progesterone-releasing T-shaped IUD (Progestasert®), which must be exchanged yearly, and a copper-bearing T-shaped device called the Cu-T-380-A (ParaGard®), which exerts its contraceptive effect for eight years.
The IUD's mechanism of action is still a matter of conjecture. In copper IUDs, it is likely that copper ions released by the device have a toxic effect on sperm, rendering them incapable of fertilizing an ovum. Progesterone-releasing IUDs probably exert their contraceptive effect by converting the endometrium to a chronically atrophic state, preventing implantation of the zygote (fertilized egg). IUDs are known to be a relatively effective contraceptive, with failure rates in the range of 0.6 to 2.0 pregnancies per one hundred women per year. While many clinicians assume that the IUD increases a woman's risk of experiencing an ectopic (tubal) pregnancy, studies clearly show that users of progesteronebearing IUDs have no increased risk of ectopic pregnancy when compared to nonusers of contraception, while users of copper IUDs experience profound protection.
Women best suited for the use of an intrauterine device are those who desire continuous contraception; who want long-term birth spacing or have completed their families but do not want to be sterilized; who require very high contraceptive efficacy; who desire a method that neither is coitus-dependent nor requires daily motivation; and who cannot use or choose not to use a barrier method or a hormonal method of contraception. IUD insertion and removal are simple office procedures that may result in temporary uterine cramping, but rarely require the use of local anesthesia or analgesia.
IUD use may result in relatively minor side effects such as heavy menstrual periods or cramping (less so with the progesterone-releasing type) and increased vaginal discharge. The relationship between IUD use and pelvic infection and consequent infertility has been studied in great detail. Early studies demonstrated that the major risk associations were recent insertion (within twenty days) and the type of IUD used (the Dalkon Shield bestowing the greatest risk). More recent studies have suggested that an IUD wearer's sexual behavior is the single most relevant risk factor for pelvic infection; a woman in a mutually monogamous sexual relationship has no increased risk of pelvic infection or tubal infertility ("blocked" or scarred tubes from PID) compared to the sexually active woman who uses no method. Conversely, women who have multiple concurrent sexual partners, or those who themselves are monogamous, but whose male partner has other sexual partners, appear to be at increased risk of IUD-associated pelvic infection.
In light of these considerations, contraindications to IUD use include the following:
- pelvic inflammatory disease within the past twelve months or recurrent PID (more than one episode in the past two years);
- post-abortal or postpartum endometritis or septic abortion in the past three months;
- known or suspected untreated endocervical gonorrhea, chlamydia, or mucopurulent cervicitis;
- undiagnosed abnormal vaginal bleeding;
- pregnancy or suspicion of pregnancy;
- history of impaired fertility in a woman who desires future pregnancy;
- known or suspected uterine or cervical malignancy;
- small uterine cavity;
- history of pelvic actinomycosis infection (not asymptomatic presence of the organism);
- known or suspected allergy to copper or, for copper IUD only, a history of Wilson's Disease (an inability to metabolize copper).
While young age may be associated with certain risky sexual behaviors, young age alone is not an absolute contraindication to IUD use. Correspondingly, a history of previous childbearing should not be an absolute prerequisite for IUD use. If a young woman is involved in a long-term mutually monogamous relationship and has no other risk factors, she may be considered a candidate for an IUD.
Barrier methods include mechanical barriers such as male and female condoms, the female diaphragm and cervical cap, and chemical barriers such as spermicidal products. Nonprescription barrier contraceptives are an important contraceptive option because of their wide availability, relative ease of use, and acceptably high efficacy when used correctly and consistently. While the contraceptive efficacies of the various barrier methods when used alone are comparable to each other (typically about twenty pregnancies per one hundred women per year), their use in combination adds significantly to their effectiveness. In addition, male latex condoms and female vaginal sheaths, when used consistently and correctly, provide a high degree of protection against both the acquisition and the transmission of a number of sexually transmitted pathogens, including gonorrhea, chlamydia, syphilis, and some viral pathogens, including hepatitis B virus and HIV (human immunodeficiency virus), the virus that causes AIDS (acquired immunodeficiency syndrome). Spermicidal products, in addition to their contraceptive effect, have in vitro microbicidal properties and appear to provide some protection against gonorrhea and chlamydia. Nonprescription barrier contraceptives include male latex and animal membrane condoms; female polyurethane vaginal sheaths; the contraceptive sponge; and spermicidal films, foams, jellies, creams, and suppositories. Contraindications include allergy to latex rubber (in the case of male condoms, diaphragm, or cervical cap), a history of significant skin irritation with acute or chronic exposure to spermicides, and inability to understand instructions for use.
The contraceptive diaphragm is a dome-shaped latex device that serves as a mechanical barrier against the cervix and also holds a spermicidal preparation in place within the vagina. The diaphragm is one of the oldest barrier methods of the modern era, and has retained its popularity because of its nonhormonal nature, ease of use, and reasonable efficacy. It may be an appropriate method of contraception for women who prefer an intercourse-related nonhormonal method of contraception; desire a barrier method that can provide continuous protection over twenty-four hours; and feel that the diaphragm is less noticeable during intercourse than other barrier methods. The diaphragm should fit comfortably with the anterior (front) rim tucked behind the pubic bone in front and the posterior (back) rim seated deep in the vagina and behind the cervix, so that the cervix is covered by the dome of the diaphragm. The largest, most comfortable diaphragm that fits well should be chosen. Use of a backup method of contraception until the return visit, or until the patient is sure that the diaphragm is staying in place during intercourse, should be advised.
No attempt should be made to use the diaphragm if the woman cannot be fitted with the device due to physical characteristics of the vagina, cervix, or uterus that interfere with proper placement, or if the proper size diaphragm is not available. Other contraindications include a recent history of frequent lower urinary tract infections (e.g., cystitis), especially if associated with prior diaphragm use; less than three months since cervical surgery; less than two weeks since midtrimester abortion or less than six weeks postpartum (after delivery of a child); allergy to rubber or to all spermicides; inability to understand instructions for use; and inability to insert, remove, and care for the device correctly.
The cervical cap is a thimble-shaped latex device that fits over the cervix and stays in place by mild suction. When used with a spermicide, it is a reliable barrier method of contraception that can be used continuously for up to forty-eight hours. In use in European countries since the 1930s, it was approved by the FDA for contraceptive use in the United States in 1988. The efficacy of the cervical cap in preventing pregnancy is similar to that of the diaphragm in nulliparous women, although the failure rate of the cap is greater in parous women.
The Prentif Cavity Rim Cervical Cap® is the only cap currently approved by the FDA. It is available in four sizes: 22-, 25-, 28-, and 31-mm internal diameter. Because cervix size may vary considerably, these sizes fit approximately 70–75 percent of women. The cap may be an appropriate choice for women who have experienced frequent urinary tract infections, especially if they occurred in association with the contraceptive diaphragm. Because there is less pressure on the urethra and bladder, the cap may be more comfortable than a diaphragm and less likely to predispose the user to a lower urinary tract infection.
The most effective methods of fertility control are those in which sexual intercourse is avoided entirely. Abstinence is defined as a limited period of time in which intercourse is avoided, while celibacy refers to a lifestyle decision in which an individual chooses to avoid intercourse for a longer time interval, which may be lifelong in some cases.
Fertility awareness methods are those in which sexually active individuals avoid unprotected intercourse during the "fertile period," which is defined as the time in each cycle that ovulation is estimated to occur. Since the ovum survives for about 48 hours after ovulation and sperm can survive in the fallopian tubes for up to five days, the length of the fertile period is about seven days in most women. Couples who practice the fertility awareness method use a barrier method of contraception with intercourse during the fertile period and no method for the remainder of the cycle. In the "natural family planning" technique, a variant of fertility awareness, intercourse is avoided entirely during the fertile period and mechanical contraceptive methods are not used at any time in the cycle. The latter approach generally is endorsed by religious groups who object to the use of other birth-control methods, which they consider to be "artificial" in nature.
Four techniques, which can be used alone or in combination, are used to estimate the fertile period.
- The calendar method, in which previous menstrual cycling patterns are charted and from which future ovulatory patterns may be predicted. This method is comparatively inaccurate, as factors such as stress or illness can affect the time of ovulation and thereby shorten or lengthen a given cycle. In addition, many women have such variable cycle lengths that the estimated duration of the fertile period can be as long as two weeks.
- The basal body charting or temperature method, which is based upon the fact that a woman's basal temperature will increase by 0.5° to1.0°F twelve to twenty-four hours after ovulation and will remain elevated until the next menstrual period. Women using this method are expected to check their temperature each morning upon arising until the temperature rise has been confirmed. Once two days have passed after the temperature rise, the fertile period is considered to be completed, and unprotected intercourse can resume until the next menstrual period.
- The cervical mucus method, also called the "Billings" or "ovulation" method, which relies upon the fact that a woman's cervical mucus becomes copious and watery in the few days before ovulation. The presence of characteristic mucus at the vaginal opening is a sign of impending ovulation and, hence, defines the existence of the fertile period.
- The sympto-thermal method uses a combination of two or more of the above techniques. The use of the cervical mucus to signal the beginning of the fertile period and the basal body temperature rise to predict its completion is the most accurate of the fertility awareness methods.
The effectiveness of the fertility awareness methods depends upon the couple's consistency of use and ability to avoid unprotected intercourse during the fertile period. When practiced correctly and consistently, the sympto-thermal method has a failure rate as low as two failures per one hundred women per year, while for the typical use failure rate for all methods of periodic abstinence is twenty pregnancies per one hundred women per year.
Voluntary surgical sterilization (VSS) is the most prevalent form of contraception in the United States; 60 percent of those surgically sterilized are women who have had tubal ligation, and 40 percent are men with vasectomies. Most couples who choose surgical sterilization have completed their families, although for some individuals this choice is prompted by an inability or unwillingness to use reversible methods of birth control. Criteria once used to determine the appropriateness of sterilization based on age and parity (number of children born) are no longer appropriate, and a woman's considered, informed decision should be respected by the provider, regardless of her age, parity, and social circumstances.
TUBAL LIGATION. The most important point to be made in counseling a woman regarding tubal ligation is that the procedure must be considered permanent and should be performed only when she is sure that she desires no further children. Alternative (reversible) methods of birth control should be discussed to ensure that these methods have not been rejected on the basis of misunderstanding or other biases. Other important aspects of counseling include a description of the surgical risks of tubal ligation, failure rates, and a comparison to the various methods of sterilization available, including vasectomy for the woman's partner. If consent cannot be obtained from a severely mentally disabled woman, a legal guardian may provide consent in some cases.
Both the federal government and individual states have regulations regarding minimum age requirements and waiting periods from the time of written consent until the date that the operation may be performed if federal or state funding is to be used. For this reason, women who plan to undergo postpartum tubal ligation should receive counseling and consent before thirty-four weeks gestation.
The surgical approach to tubal ligation is primarily dependent upon whether the procedure is performed in the postpartum period, or longer than six weeks after delivery, in which case it is considered to be an interval tubal ligation. In a postpartum tubal ligation, a minilaparotomy performed within four to twenty-four hours of delivery is the preferred approach subsequent to a vaginal delivery. After receiving a regional or general anesthetic, a three-centimeter curvilinear or vertical incision is made immediately under the umbilicus. Once the peritoneal cavity has been entered, either the operator's finger can be used to sweep each tube into the incision or each tube can be grasped under direct vision. In either case, positive identification of the tube can be made by visualizing the fringelike portion at the abdominal end of each tube and by demonstrating that the nearby round ligament is uninvolved. After completion of the tubal occlusion, each excised tubal fragment must be sent for histological confirmation. In a woman delivered by cesarean section, any of the three techniques described below can be performed after repair of the uterine incision has been completed.
A number of techniques are available when there is direct access to the fallopian tubes via minilaparotomy or cesarean section. They include the following methods:
- modified Pomeroy method, in which two ligatures (sutures, "ties") are placed in the midportion of each of the tubes and then the pieces of tube between the ligatures are removed. The closed ends retract, leaving a gap between the closed-off tubal segments.
- Irving method, whereby the tubal stump nearest the uterus is tucked into a tunnel made in the myometrium (muscular structure) of the large upper part of the uterus.
- Uchida method, which involves excision of a five-centimeter segment of tube, followed by burying the tubal stump farthest from the uterus within the mesosalpinx (the free margin of the upper part of the broad ligament).
While the failure rates of the Irving and Uchida techniques are exceedingly low (less than 1/1,000) in comparison to the Pomeroy method (1/250), the former take longer to perform and therefore are relegated to special cases.
Interval tubal ligation may be performed with a laparoscope (a narrow lighted tube) via a low minilaparotomy incision (a small horizontal incision, 2–5 cm long, just above the pubic hairline), the former being much more prevalent in the United States. Laparoscopic approaches ("band-aid" surgery) include either open or closed laparoscopy, and both one- and two-puncture instruments (laparoscopes) are available. While a large majority of laparoscopic tubal ligations are performed under general anesthesia, there is a growing trend to perform these procedures under local anesthesia, thereby reducing cost and avoiding the risk of general anesthetic complications, which is the most common cause of tubal ligation deaths. If local anesthesia is used, the tubes must be bathed in a long-acting local anesthetic, then banded or clipped, rather than electrocoagulated (coagulation or clotting of tissue using a high-frequency electric current).
Minilaparotomy for interval tubal ligation is performed via a three-centimeter low horizontal incision. Because of the difficulty entailed in working through a small incision, the procedure is facilitated by using a uterine elevator, an instrument placed in the vagina to lift the uterus. The procedure may be performed with general, regional, or local anesthesia. Minilaparotomy is contraindicated when the patient is obese, has an enlarged or immobile uterus, or when adnexal disease (in the areas adjacent to the uterus, e.g., ovaries and tubes) such as endometriosis is suspected. Nonetheless, minilaparotomy can be a safer, simpler, and less expensive procedure than laparoscopy, which requires more technical equipment and endoscopy experience.
If minilaparotomy is chosen, any of the occlusion techniques outlined above for postpartum tubal ligation may be used. In addition, spring-loaded tubal clips are available that can be easily applied through a minilaparotomy incision. With the laparoscopic approach, three methods of tubal occlusion are available:
- Electrocautery, with a coagulation or "blend" current, used at two or three sites along the mid-fallopian tube. Either unipolar or bipolar cautery may be used; while bipolar cautery is safer (since it is less prone to cause bowel burns), it takes longer and has a higher failure rate. Unipolar electrocautery is faster and more effective, but there is a risk of sparking between the electrode and the bowel, resulting in an unrecognized injury. Fallopian tubes occluded by electrocautery may be quite difficult to reanastomose (reconnect, in the event the woman changes her mind and wants to try to achieve pregnancy) because of extensive scarring.
- Silastic (silicone rubber) rings may be applied with a forceps-type applicator to a loop of midportion fallopian tube. This approach avoids the risk of electrical injury to the bowel and preserves much larger segments of healthy ends of the severed fallopian tube should later reversal be considered.
- Spring-loaded clips may be placed at a single site in the middle of the tube and can be used with double-puncture laparoscopy or at minilaparotomy.
The provider must explain that with tubal interruption alone, no organ is removed; tubal sterilization merely prevents conception. The operation is not "desexing" and will not reduce libido, vary the woman's menses, or alter her appearance. There is usually no adverse change in sexual function following tubal sterilization; on the contrary, many women who feared pregnancy before the operation report increased satisfaction in sexual intercourse and are pleased with the operative result. However, 2 to 5 percent report less frequent orgasm and a similar percentage have delayed regret that the procedure was performed.
Only hypophysectomy (excision of the pituitary gland), bilateral oophorectomy (removal of both ovaries), and ovarian damage by radiation are certain methods of sterilization. Abdominal and tubal pregnancies have occurred (rarely) even after total hysterectomy (removal of the uterus). Oophorectomy and sterilization by radiation are usually followed within four weeks by vasomotor reactions (symptoms associated with menopause such as "hot flashes") and a gradual diminution in libido or sexual satisfaction during the next six months.
VASECTOMY. Sterilization of the man by vasectomy is both less dangerous and less expensive than tubal ligation, as it is routinely performed as an office procedure under local anesthesia. Through one or two small incisions in the scrotum, the vas deferens (the tube or duct that carries sperm) is isolated and occluded and usually a small segment of each vas is removed. Neither physiologic impotence nor changes in libido result from the procedure. Sterility cannot be assumed until postoperative ejaculates are found to be completely free of sperm. Failure of the vasectomy, as manifested by pregnancy in a partner, occurs in 0.1 percent of patients. Medical risks of vasectomy include hematoma (blood clot or bruise) formation, epididymitis (congestion or inflammation of the epididymis, the coiled tubular structure where sperm cells mature), spontaneous recanalization of the vas (reconnection of the ends with restored patency) (incidence of less than 1%), and the development of a spermatocele (cystic nodule containing sperm). Atrophy of the testes very rarely results from ligation of excessive vasculature (blood supply). Vasectomy often is reversible—up to 90 percent in some reports—but requires expensive microsurgery and special skill with no guarantee of success. Pregnancy results in only about 60 percent of cases after reversal; factors that influence success include (but are not limited to) the surgeon's skill, the type of procedure used, and time interval since vasectomy.
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