Prevention of unwanted pregnancy is a main goal of clinicians who care for sexually active adolescents.1 This article is based on the concept that there are many youths who will accept contraceptive measures if advised about them in a confidential manner by the knowledgeable physician or health-care provider.
Table 1 outlines some of the methods useful in preventing conception in adolescence, as well as other methods that do not work as well and thus are not recommended.
Since their introduction, in I960, oral contraceptives, or birth-control pills (estrogen and progesterone), have become a safe, popular, and effective method of contraception.2·3 Recent reviews have listed the many organ systems and laboratory test results that may be affected by birth control pills.4"6 Pill side effects are usually listed as estrogenrelated (such as nausea, emesis, edema, dysmenorrhea, leukorrhea, and chloasma) or as progesterone-related (such as monilial vaginitis, increased appetite, short menses, acne, hirsutism, or alopecia).
Sometimes, changing from a higher- to a lowerestrogen -con ten t preparation may relieve symptoms associated with excess estrogen. Such manipulation of dosages is limited, however, since it is currently recommended that teenage patients be given a pill with no higher than 50 µ g. of estrogen , in order to reduce risk of such complications as thromboembolism. Very-low-dose estrogen pills (20-35 Mg-) have been used but often result in menstrual irregularity or breakthrough bleeding. Whether or not reduction of progesterone-related symptoms in a person can be accomplished by changing the brand of birth-control pills one uses has not been demonstrated in teenagers.
There are many potential problems associated with the use of birth-control pills that physicians and patients must consider before the physician gives an adolescent a prescription. The six absolute contraindications to their use are listed in the box. Thromboembolism seems to be a major complication of pill use, but in my opinion the risk to women under age 30 is probably minimal, particularly if they do not smoke. Though the risk of hypertension, circulatory diseases, and hypercoagulation states is increased, these should not pose a major threat to teenagers who have appropriate medical screening. The management of patients on the pill who need elective surgery is unclear. There is question whether the pill should be stopped four to six weeks before the surgery and/or whether the patient should be given low-dose heparin to reduce the risk of postoperative thrombosis.
Cancer and the pill. There is no actual evidence that the teenager is at significant risk for developing cancer, even though there is general concern about the carcinogenic potential of the pill. I am not aware of any current data showing that use of the combined oral contraceptive causes breast, endometrial, or cervical cancer.7 Recently there has been concern that the pill may cause pituitary tumors, but there are no sound data.8
Postpill amenorrhea. Amenorrhea for six months or longer after cessation of the pill is reported in 0.2 to 3 percent of women. There seem to be many factors associated with this problem, including previous menstrual irregularity, previous weight loss or very thin physique, environmental or work changes, stress, and late menarche.9 The current recommendation is to start the teenager on birthcontrol pills only if she has been menstruating regularly for one or two years. If postpill amenorrhea develops, extensive medical evaluation is usually not undertaken for at least six months. Most patients will eventually ovulate, but some may require fertility drugs.
METHODS OF CONTRACEPTION
Diabetes mellitus. Many authors5 do not recommend oral contraceptives for insulin-requiring diabetics, because of the rise in blood sugar and triglycérides observed in many women. Some diabetics can be managed on oral contraceptives, however, if it is kept in mind that they will have higher insulin needs. The increased risk for diabetic women who become pregnant must also be considered. There is no risk that normal persons will develop diabetes mellitus because they are taking the pill.10 Thus, though the pill is not the first choice of contraception in diabetics, it is not absolutely contraindicated. Each patient must be individually evaluated. The progesterone-only pill (mini-pill) may be useful, but data on use of this pill by teenagers are limited.
Epilepsy. Seizure disorders per se do not constitute an absolute contraindication to oral contraceptive 112 use.* It may be necessary to increase antiepileptic medication doses to control the epilepsy, but this increase in dosage may be preferable to an unwanted pregnancy. The condition of patients with certain forms of epilepsy may even be improved when they are taking the mini-pill.11 A problem of unknown proportions is the reported failure of oral contraceptives secondary to increased metabolism, which is due to anticonvulsant medication, and which induces a rise in microsomal enzymes of the liver. The risk to the individual epileptic patient on oral contraceptives is not clear.
Liver disease. Active liver disease is a contraindication to the use of oral contraceptives.5 Once the liver-function tests return to normal in patients who have had viral hepatitis, starting oral contraceptives is possible without evidence of liver damage. The oral contraceptives do seem to increase the risk of the patient for benign hepatic adenomas and focal nodular hyperplasia of the liver. Sudden massive intraperitoneal hemorrhage from the nodular hyperplasia has been reported.12 Patients on oral contraceptives should be periodically examined, therefore, for enlarging right upper-quadrant masses.
Other complications. Oral contraceptives have produced many other effects that may need to be monitored in certain adolescent patients.5
Headaches, vaginitis. Some women notice that migraine headaches are worse while they are on the pill; others report monilial vaginitis and even gingival inflammation.13
Nursing. The effect on lactation is not clear, but a decrease in milk volume or in lipid content of the milk, or both, may occur. The mini-pill has no major effect on lactation.
Pregnancy. The patient should be told to stop the pill if pregnancy is suspected, since oral contraceptives may increase the risk that the fetus will have congenital deformities (limb-reduction defects and cardiac anomalies). T
Diarrhea. Diarrhea may result in failure of the body to absorb the pill, which could result in conception ("pill failure").
Failure to take the pill. The physician should emphasize to teenage patients that it is important to take the pill each day. Missing just one pill may lead to breakthrough and menstrual bleeding;14 missing two pills or more increases the chances of becoming pregnant.
INTRAUTERINE DEVICES (IUD)
The use of intrauterine devices for contraception has been controversial since Richter first used a silkworm-gut type in 1909. Though Graefenberg published a favorable report on the IUD in 1929, widespread interest in this method did not begin until after Oppenheimer's report in 1959, a time that coincided with increasing interest in the birthcontrol pill. For many years physicians believed that the Graefenberg ring - the original IUD - was not suitable for general use. Then it was discovered that a smaller contraceptive device could be manufactured if copper was added to the IUD, resulting in a re-evaluation of its suitability for teenagers.15 Mechanism. The copper IUD and nonmedicated IUDs apparently prevent conception by inhibiting blastocyst implantation. Although the IUD is considered an effective method of contraception, its failure rate is two or more times that of the combined oral contraceptive.
The main device being used by nulliparous adolescents is the copper IUD. Many types are being used or are under investigation, including the copper 7 and copper T (T Cu 200, T Cu 300, or T Cu 38OA)16
Modifications of the basic IUD design are continually being made, because the design qualities determine both longevity and effectiveness of the devices. The T Cu 38OA may become the preferred copper IUD in the near future, since it seems to be well tolerated by most women and can remain in place for several years. By way of comparison, it is recommended that the copper 7 be removed after two or three years.
The Progestasert IUD is the other medicated IUD in use. Progesterone is added to the IUD structure. It is well tolerated but may lead to an increased ectopic-pregnancy rate, and currently it must be removed every year.
Insertion. The IUD should be inserted by a health professional who has been adequately trained in the procedure, in order to ensure minimal complications.17 The position, size, and accessibility of the uterus for IUD insertion must be determined accurately. A uterine sound is used to determine the depth and direction of the uterus. The IUD is inserted and released high in the uterine cavity in a transverse plane. It is placed during menses to ensure that the patient is not pregnant and to allow for easier insertion. The marker strings are cut within 2-4 cm. of the external cervical os. It is helpful to write down the IUD type each patient has received, as many are not aware of which one they have.18
Contraindications. Contraindications to IUD use include pelvic infections, cervical or uterine hypoplasia, uterine malignancy, the fact that the patient is at high risk for bacterial endocarditis, severe dysmenorrhea, and severe menorrhagia.17
Complications. Pain during insertion, increased dysmenorrhea, increased menstrual bleeding with anemia, expulsion, ectopie pregnancy, spontaneous abortion, uterine perforation, and pelvic inflammatory disease are among the complications that have been reported from IUD use. Increased dysmenorrhea and bleeding are the main complications. Girls may have longer periods with less blood loss and less intermenstrual spotting when copper IUDs are used instead of nonmedicated IUDs.19
It is recommended that serum ferritin levels be monitored to check for IUD-associated anemia.20 Prostaglandin-inhibitor medications, such as naproxen sodium, may relieve dysmenorrhea associated with IUDs, since the mechanism for this increased pain may be increased endometrial prostaglandin synthesis.21 A progesterone- type IUD may be useful in patients with dysmenorrhea, as the progesterone may reduce endometrial prostaglandin levels.
One of the common problems associated with IUDs is the inability to locate the IUD strings after the device has been inserted.22 Usually this means that the strings have retracted into the uterus, but sometimes it indicates that the IUD has been expelled or has perforated the uterus. Fortunately, a uterine perforation is rare, but it may be more dangerous with the copper IUD because of the irritating effect of copper within the peritoneal cavity.23 Patients at high risk for bacterial endocarditis should not be given an IUD.
Adolescents who use the IUD have a three-toninefold increase in pelvic inflammatory disease.17 The IUD user at highest risk for infection seems to be the young promiscuous nullipara from a low socioeconomic background. Patients with IUDs also seem at higher risk for ovarian abscesses, septic abortions, and pelvic actinomycosis. Septic arthritis and tenosynovitis related to an IUD have also been reported.
The literature thus indicates that IUD wearers are at real risk for the development of pelvic infection. The teenager who is sexually active and who has many partners or one promiscuous partner is particularly at risk. Consequences of IUD complications, which include pelvic inflammatory disease, can be chronic abdominal pain and infertility.
Summary on the IUD. The copper device seems to have an important place both now and in the near future as a contraceptive device for some young women. Many physicians, however, do not recommend the IUD for adolescent patients because of the complications. If the IUD is selected as the best contraceptive method for a particular teenager, the physician should provide careful medical followup.2,5,15,23
The diaphragm, the condom, and various vaginal contraceptives are the barrier methods of preventing conception. All have been in use for many years - some for centuries.
The diaphragm. The diaphragm is a rubber cap with a metal spring in the rim. It is placed in the vagina with contraceptive cream or jelly before coitus. Its contraceptive effect is due to the spermicidal action of the cream or jelly, as well as to the mechanical blocking of the sperm by the closing off of the external cervical os. The diaphragm was developed by the German physician Hasse in 1882 but did not become widely used in this country until Margaret Sanger introduced it, in the 1920s.
Its effectiveness varies greatly. Pregnancy rates of users have been reported to range from 2.4 to 29 per 1 OO woman-years.24 Women can use this method and can very effectively prevent conception if they are properly motivated. Many women do not like to use the diaphragm, however, because of the necessity that it be inserted in advance of each anticipated act of coitus, because some skill is required for its effective insertion, because insertion requires intimate touching of one's own genitals, because of their concern that diaphragm use makes them more sensually oriented than their partners, and for other reasons.1
I believe that the diaphragm is a contraceptive method that should be encouraged for adolescent use, since its use is accompanied by few side effects. s·24"26 Occasionally a mild stinging or burning of the vaginal walls or penis is reported, but allergic reaction to the latex rubber or cream is rare. A foreign-body vaginitis will occur if the diaphragm is left in place for a few days or longer. Dyspareunia may occur if too large a diaphragm is prescribed.
Realization of its safety (compared with the oral contraceptive or IUD) and potential efficacy may be the reasons for the reported increase in its use by older teenagers and young adult women noted since 1975. 27 Some find it useful to use a diaphragm while changing contraceptives, such as when stopping the pill and waiting for the next menstrual period for an IUD insertion.28 An added benefit of diaphragm usage may be increased protection from cervical carcinoma, as lower rates are noted in women using this form of contraception.25
TYPES OF DIAPHRAGMS
Four types of diaphragms (Table 2) are available, ranging from 50 mm. to 105 mm. in diameter. The coil-spring or flat-spring diaphragms are used by most women. They are held in place by the spring tension of the rim, the vaginal muscle tone, and the pubic symphysis.
Fitting the diaphragm. When a teenage patient chooses the diaphragm as a contraceptive method, a careful fitting should be done by the physician. The largest size possible should be selected that will fit comfortably with the posterior rim behind (covering) the cervix and the anterior rim in a groove behind the symphysis pubis.26 The patient should not feel it in place, though occasionally the male partner will feel it during coitus. Since the vagina swells during sexual excitement, a diaphragm that is too small will not accomplish its purpose.
The physician should check the diaphragm within a short time after its initial fitting during a subsequent office visit, to ensure proper fit. Tensing of the vaginal muscles during the original fitting can result in prescription of a functional diaphragm that is too small to be effective. A weight gain or loss of 1 0-1 5 pounds or more will necessitate a second fitting, as another-size diaphragm may be needed.
The patient must receive careful instructions about the use of the diaphragm so that she understands the contraceptive mechanism of the diaphragm and its insertion and removal. She should practice putting it in place before its actual use for contraception. She should add the contraceptive cream or jelly and then insert the diaphragm before coitus. If more than six hours passes before coitus or if another coital act occurs, additional cream should be applied. The diaphragm should not be removed, nor should the patient bathe or douche until six to eight hours after coitus. The diaphragm is then removed and cleaned with warm water and mild soap. It is dried and stored with cornstarch or unscented talcum powder. Many agents can erode the latex, including petrolatum, heat, hot water, newsprint,- and scented soaps.
Contraindications. Contraindications to use of the diaphragm are indicated in the box. If your patient wishes to have an ìntravaginal-barrier method of contraception and the diaphragm is contraindicated, you may be able to provide her with a smaller rubber cap that fits only over the cervix. Such cervical caps have been in use in Europe for several years, but only infrequently in this country. Other devices have been described as well, including the vault cap and the vimule.29 These cover beyond the cervix and, like the cervical cap, are held in place by suction,
Condom. The first condom is attributed to Gabriele Fallopius (1523-80), the Italian anatomist, who in 1564 recommended a damp linen cloth be wrapped around the penis during intercourse to protect one from acquiring syphilis. The term condom is believed to be derived from Edward Conton (1600-49), the physician in Charles II's court who devised a sheath to protect the promiscuous king from venerai disease. Probably the most famous description of the condom comes from the letter written by Madame de Sévigne'( 1 626-96) to her daughter: "Armor against enjoyment and spiderweb against danger."
REASONS GIVEN FOR NOT USING CONDOMS AS CONTRACEPTIVES
Use of the condom is credited with causing the decline in births in Europe during the 19th century. Today, however, the condom is the most popular contraceptive device in the world, and since serious research into male contraception began only in 1971 , it will probably remain the major male contraceptive for teenagers in the near future,30
The condom, or prophylactic, is potentially a very effective method of contraception.31 Although reported pregnancy failure rates vary widely (from 2.6 to 30 pregnancies per 100 womanyears), it should be observed that proper technique and motivation can transfer the simple condom into a contraceptive method as effective as the modern IUD. It has been demonstrated that some adults and teenagers can accept and utilize this method. However, for many reasons (Table 3), it remains underutilized in the United States, as many males do not choose to use it.
I believe that the pediatrician should stress the advantages of the condom for adolescent patients over some other methods of birth control (Table 4). When used properly, it does protect against sexually transmitted diseases,32 despite Madame de Sévigné's skeptical statement. Partial protection from gonorrhea in particular is reported, but not from nongonococcal u ret h riti s , which often is due to Chlamydia trachomatis.33 An advantage to the girl is that she is at reduced risk for acquiring such venereal organisms as Neisseria gonorrhoeae^ Trichomonas vaginalis. Candida albicans, and herpes simplex if her infected partner uses a condom.
Another potential advantage to the adolescent girl is that the boy's willingness to accept responsibility for using a condom may reflect his willingness to accept other responsibilities stemming from their sexual relationship, such as pregnancy, should it occur, or the avoidance of venereal disease or the obligation of having it treated promptly if it is acquired. Reduced incidence of cervical carcinoma in women whose sexual partners have used condoms has been reported.34 A more recent study35 suggests that young women may place themselves at increased risk for developing breast cancer later in life if they have sexual relations consistently with partners who use condoms. These data need clarification.
ADVANTAGES OF THE CONDOM AS A CONTRACEPTIVE
I believe that the pediatrician should encourage the use of the condom as a safe, practical, and effective method for preventing conception in teenage patients. To allow for a more useful discussion, the pediatrician, if possible, should see the teenage girl with her male partner in his office. It is important for them to know that there are many styles of latex-rubber condoms of high quality that are available, both plain and reservoir-tipped. Lubricated latex condoms with reservoir tips are best for teenagers to use; those made from sheep cecum are generally too expensive.
ADVANTAGES OF VAGINAL CONTRACEPTIVES
The boy should be instructed to place the condom over his penis before coitus and to hold the rubber rim when withdrawing his penis. If uncircumcised, he should withdraw his foreskin before unrolling the prophylactic the full length of the erect penis. Male compliance may be increased if the girl places the condom on the penis. Teenage patients should be told that condoms can be damaged and rendered ineffective by improper storage (such as several months inside a wallet), by high temperature, or by being coated with petroleum jelly.
Vaginal contraceptives. A third type of barrier contraceptive is the spermicidal vaginal suppository. Various types of vaginal contraceptives have been in use for centuries. Significant advances were not made, however, until after World War II, following the reports by Baker et al.36 and Eastman and Seidelo.37
Surface- active agents such as nonoxynol-9) were developed in the 1950s; these chemicals attached to the sperm directly, broke down its cell wall by reducing the surface tension, and thus killed the sperm. A commercially available vaginal aerosol foam was first described in 1960, and by the mid- to late 1960s, many vehicles for vaginal contraceptives were available: jellies, creams, pastes, powders, suppositories, foaming powders, and tablets. The most recent form is the "C-film" (contraceptive film),38 introduced in 1973. This is a water-soluble plastic film that is inserted into the vagina before coitus.
All of the vaginal contraceptives consist of an inner carrier base or vehicle containing an active spermicidal agent, such as nonoxynol-9. Bactericidal chemicals, such as phenylmercuric acetate and ricinoleic acids, may also be present.
Effectiveness of the vaginal contraceptives varies considerably, with pregnancy rates (i.e., failure rates) ranging from 1.3 to 38 per 100 womanyears.24 Several studies suggest, however, that low pregnancy rates are possible with proper technique and motivation.39·40
Many adolescents dislike using these agents, finding them "too messy" or inconvenient. Many, as in the case of the diaphragm, dislike touching their genitals in this way or having to anticipate and plan in advance for each act of sexual intercourse. A few report mild burning or irritation with the use of spermicides, Yet, as Table 5 indicates, there are many advantages to vaginal contraceptives.
A number of types of vaginal contraceptives are now on the market.* Foam products seem to be the best vehicle, and cream the second best, because of the better spermicidal distribution in the vagina. Allergic reactions, rarely reported, usually disappear if the person switches to a different brand,
As with the use of other contraceptives, it is important for the physician to teach the teenage patient proper technique. The agent should be placed high in the vagina up to one hour before coitus. One should allow 1 5 to 30 minutes for the suppositories, jellies, or creams to melt through the action of body heat. Suppositories should be placed close to the external cervical os, and so the patient should be taught where the external cervical os is located. If there is further intercourse, additional amounts of the agent should be added. Douching or bathing should not be attempted for at least six hours. Teenagers using vaginal contraceptives as a barrier to pregnancy should be urged to combine them with other barrier methods.
A new vaginal suppository (Encare Oval) recently has been introduced with claims that it is more effective than previous methods. There are no substantial studies that I am aware of to indicate that it is any better than other available vaginal contraceptives,41 and its side effects (burning, irritation of the vagina or penis, mild vaginal discharge) are similar.
POSTCOlTAL CONTRACEPTIVES (MORNING-AFTER PILL)
Diethylstilbestrol (DES) has been approved by the Food and Drug Administration for use as a postcoital contraceptive method in emergency situations, such as after rape.42·43 The drug is given orally at a dose of 25 mg. twice daily for five days; administration should start within 72 hours of coitus.
The main immediate side effect of this high-dose estrogen therapy is nausea and emesis (in as many as 50 percent of those who receive the treatment). Pediatricians should also be aware of the prolonged latency in the expression of the drug's effect and obtain signed consent before prescribing the drug to a pediatrie patient. This drug should not, of course, be prescribed to pediatrie patients who plan on pregnancy in the near future, because of the high incidence of genitourinary anomalies in male offspring and clear-cell vaginal carcinoma or adenosis in female offspring of women who have taken DES during gestation.*
Depo-medroxyprogesterone acetate has not been approved by the Food and Drug Administration for use as a contraceptive. It has been reported44 to be as effective a contraceptive as the combined birth-control pill, both having pregnancy (i.e., failure) rates of less than 1 per 100 womanyears.
MISCELLANEOUS CONTRACEPTIVE MEASURES
Abstinence, rhythm, coitus interruptus, use of the douche immediately after intercourse, and noncoital sex are some of the other contraceptive measures sometimes advocated.
Abstinence. Approximately 45 percent or more of teenagers at age 1 9 are not sexually active45 and yet may feel under peer pressure to engage in coital activity. The physician may relieve an adolescent patient's anxiety considerably by reassuring him or her that there is no physiologic or psychologic reason to engage in sexual activity until a person feels ready to do so. Some teenagers find such advice reassuring and helpful.
Rhythm (periodic abstinence). Though a popular method among teenagers,46·47 periodic abstinence is a very poor contraceptive technique indeed during the adolescent years, because menstrual cycles are frequently irregular and youth are frequently ignorant about which times are actually "safe." Even when the girl faithfully records basal body temperatures, notes type of vaginal discharge, and pays close attention to the calendar, she should be told that use of the rhythm method places her at considerable risk of becoming pregnant.48
Lactation. Breast-feeding does provide some protection against becoming pregnant but should not be totally relied on as the contraceptive method for the couple.49 Nearly all lactating women ovulate within one year of delivery. The average onset of ovulation after delivery for breast-feeding mothers is approximately seven months.50 Early supplementation will hasten the time of ovulation.51
Both menstruation and ovulation can occur in a lactating mother, so lactation should serve as a stimulus and not as a substitute for other methods of birth control. Lactation, of course, does not occur after an abortion or stillbirth.
Coitus interruptus (withdrawal, "the French method," onanism). This method, mentioned in the Bible,52 has been attributed by some to be responsible for a decline in the number of births in England and France during the 17th and 18th centuries.53 It is a popular contraceptive method among some but should be regarded as an ineffective means of birth control, S3·54 Teenagers in particular should not rely on coitus interruptus, since "it requires a great deal of control. The pediatrician should be aware, of course, that opinion is sometimes expressed in lay teen articles - and even in medical literature - that coitus interruptus can be used since it is better than no method at all. It is still not known with certainty whether there are viable sperm in the pre-ejaculate fluid.
Douching. Douching with warm water is important for perineal hygiene and is not harmful after intercourse. But it is definitely not a method of contraception.46 It takes about five minutes for the sperm to travel from the external cervical os to the fallopian tubes.55 The teenage myth of "cola douche" must be placed in the same category as other, equally false but persistent adolescent rumors about birth control, such as that the girl won't get pregnant if the act of intercourse is performed while standing or that it is necessary to take a birth-control pill only after one has had coitus. Non coital sex. Teenagers engage in various sexual activities in addition to coitus, such as petting, hand holding, and kissing. Masturbation is often proposed as an alternative to premarital sex." Sterilization, abortion.57 These methods of preventing birth are not considered appropriate for teenage patients and will not be treated in this article.
Teenagers sometimes have homosexual experiences - or at least feelings - and may be confused by the message of some: that such a life style is good because it is a form of effective contraception in a crowded world. Frank discussion between patient and physician should reveal that, though some do choose this life style, homosexuality is not a form of contraception per se. In addition, the homosexual youth should be reminded that the condom, though unpopular in gay circles, is an excellent means of preventing the transmission or acquisition of the many venereal diseases associated with this life style among males.58-59
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METHODS OF CONTRACEPTION
TYPES OF DIAPHRAGMS
REASONS GIVEN FOR NOT USING CONDOMS AS CONTRACEPTIVES
ADVANTAGES OF THE CONDOM AS A CONTRACEPTIVE
ADVANTAGES OF VAGINAL CONTRACEPTIVES