This chapter should be cited as follows:
Update due

Adolescent Contraception

Authors

INTRODUCTION

There are 25 million teenagers in the United States, 4 million of whom are sexually active. More than 1 million females aged 15 to 19 years become pregnant each year, and the vast majority of these pregnancies are unintended.1 Fifty percent of young women have sex by age 17.4 years, and 50% of male teens report having intercourse by age 16.6 years.2 By their 18th birthday, 56% of female adolescents and 73% of male adolescents have made their sexual debut (“coitarche”). Factors that increase the likelihood of early sexual activity in female teens include lower socioeconomic status, living in a single parent home, engaging in other risky behaviors such as alcohol or drug consumption, and having peers that are already sexually active. In young men and African-American women, the pace and timing of pubertal development is also a strong predictor (Table 1).3

TABLE 1. Factors That Increase the Risk of Early Sexual Activity in Adolescents

  Low socioeconomic status
  Living in a single-parent home
  Engaging in risk-taking behavior (e.g. cigarette, alcohol, drug use)
  Having sexually active peers
  In some cases, early or rapid pubertal development

The younger the teen at the time of coitarche, the more likely it is that the sexual episode was not voluntary. In one study, 74% of young women who had intercourse before age 14 years and 60% of those who had sex before age 15 years report being forced to have sex.4

The same factors that influence the likelihood that a teen will engage in sexual intercourse at an early age are also associated with contraceptive use. Risk-taking behaviors such as substance abuse and unprotected sex tend to be linked. Teens who engage in risky behavior are more likely to be depressed or less able to handle the stresses of adolescence. Lower socioeconomic status and living in a single parentage are often the sequelae of similar sexual behavior in the parent, and thus may be perceived as condoned by the teen. Teenagers who live in poor urban neighborhoods where violence and child neglect are everyday occurrences may also feel doomed to a lifestyle in which taking risks is common.

The consequences of early sexual activity without contraception are well known. These youngsters are more likely to experience an unwanted pregnancy at an earlier age, thus increasing the chances that they will drop out of and never return to school, limiting them to lower-paying job opportunities and a future as low-income, single parents themselves. Thus, the cycle often perpetuates itself.

The goals of the health care practitioner in the 21st century should be to increase awareness and education in younger teens regarding the sequelae of early sexual activity, particularly if undertaken without contraceptive protection. Low-cost, confidential contraceptive services and information and treatment regarding sexually transmitted diseases (STDs) must be provided in a private, reassuring, and confidential setting. Health care providers should also review the benefits unique to various types of contraception with each adolescent to mutually select the best method for her and her partner.5,6,7

In the area of sexuality, ignorance and denial remain dominant traits in the United States. Despite advances in scientific technology and research, the topic of sexual intercourse is taboo in most American households, and few schools have adequate sex education programs.8 As a result, most U.S. youths first learn about sex outside the home, and as such, their attitudes toward birth control are less influenced by parental standards then by those of their misinformed, misguided peer group. This unwillingness on the part of elders to confront the issue of sex education persists despite the fact that numerous studies have demonstrated that teenagers armed with basic knowledge of reproductive biology and contraceptive methods are less likely to become sexually promiscuous, become pregnant, or contract STDs.3 The home in which sexual behavior is discussed openly and honestly, with parents who are receptive to the special needs of the adolescent, is much less likely to have to endure the heartbreak of a teen's undesired, out-of-wedlock pregnancy, dropping out of school, or running away.

The following factors should be considered when helping an adolescent choose a contraceptive method.

  Acceptability: Is it a method the patient will continue to use consistently?
  Effectiveness of method and frequency of intercourse: Does the method lend itself to the unplanned coital episode often seen in this age group?
  Number of partners and STD concerns: Is the patient adequately protected?
  Cost of and access to medical care: Can the patient afford the method on a long-term basis?
  Motivation and self-discipline of patient and male partner: Will a need to interrupt foreplay result in nonuse of the method?
  Safety and risk: Will short-term convenience result in long-term drawbacks?
  Personal religious and/or parental philosophy: Will it influence usage?

The health care professional's pragmatic approach to the individual adolescent and her lifestyle will result in a choice that is optimal in effectiveness and use. It is essential to foster a supportive attitude of trust and confidentiality; encouraging follow-up ensures patient satisfaction with her chosen method, early detection of side-effects or complications, and opportunity to switch to another type of contraception as appropriate.

COMBINED ORAL CONTRACEPTIVE PILLS

Oral contraceptives are the method of choice for many U.S. teenagers.9 Advantages include its high effectiveness rate (92%–97%), even with an occasional missed or late pill, and the lack of requirement for interruption of foreplay or cooperation of the male partner. Multiple other noncontraceptive benefits of the pill have been well cited but are generally unappreciated by younger women (Table 2).10,11 Most notable is the recent approval by the U.S. Food and Drug Administration (FDA) of one oral contraceptive pill, Ortho Tri-Cyclen (35 μg ethinyl estradiol with triphasic norgestimate), for the treatment of acne, even when contraception is not the primary goal.12 Because acne and hirsutism are prevalent during the teenage years, this may prove to be the pill of choice in adolescents with these attendant problems. In general, pills containing a low androgenic progestin, such as norgestimate or desogestrel, are preferred in this age group.

TABLE 2. Noncontraceptive Health Benefits of Oral Contraceptives

  Increased menstrual cycle regularity
  Decreased incidence of

  Dysmenorrhea
  Menorrhagia
  Iron-deficiency anemia
  Dysfunctional bleeding
  Premenstrual syndrome


  Decreased incidence of benign breast disease
  Decreased incidence of pelvic inflammatory disease and sequelae, including ectopic pregnancy
  Decreased incidence of functional ovarian cysts
  Decreased occurrence acne and severity
  Decreased risk of ovarian cancer
  Decreased risk of endometrial cancer
  Decreased risk of colon cancer
  Improved bone density
  Decreased incidence of rheumatoid arthritis

Furthermore, the common usage of lower-dose pills (i.e. those that contain 35 μg or less of ethinyl estradiol) has made former contraindications no longer relevant. Compliant teens with homozygous sickle cell disease, mitral valve prolapse without regurgitation, and controlled hypertension and/or diabetes mellitus (without renal complications or retinopathy) who have no other risk factors such as smoking may safely use low-dose combined oral contraceptive pills.13,14

All adolescents should be thoroughly counselled during the first visit to encourage acceptance and reduce doubts inherent in the selection of any birth control method. Positive presensitization such as this is best accomplished by addressing questions before they are asked, such as those regarding weight gain and breakthrough bleeding. Teens who are reassured that a low-dose oral contraceptive pill will not cause weight gain and in fact will provide multiple other noncontraceptive benefits are much more likely to continue to take their pills on a long-term basis.7,11,15 For example, young women who experience relief of severe dysmenorrhea while on the pill are eight times more likely to be consistent oral contraceptive users.16

The major drawback to oral contraceptives is the motivation required to take a pill on a daily basis. However, even without perfect adherence, the pill is somewhat “forgiving”; the highest accidental pregnancy rates in less-than-perfect users in the United States are reported at 8% (i.e. 92% effectiveness).17 Better-than-average users are cited as having a 4% mean pregnancy rate, whereas perfect-use pregnancy rates are less than 1%, even with low-dose pills (i.e. those containing 35 μg or less of ethinyl estradiol).18

As always, oral contraceptive users should be counselled regarding a “belt and suspenders” approach to sexual activity: using oral contraceptives to prevent pregnancy and a latex condom with spermicide to protect against STDs.15,19

There are a few conditions in which the use of an oral contraceptive containing 50-μg of estrogen should be considered: namely, the long-term use of drugs that induce hepatic enzymes and thus speed up estrogen metabolism, thereby lowering the oral contraceptive's efficacy. These medications include the antiepileptic agents phenytoin, phenobarbital, primidone, ethosuximide, and carbamazepine; the antitubercular agent rifampin; and the antifungal agent griseofulvin.20,21

PROGESTIN-ONLY PILL

The progestin-only pill, also known as the mini-pill, available in the United States today contains either 0.35 mg norethindrone or 0.75 mg norgestrel. Each pack contains 28 active tablets which, unlike other oral contraceptives, are taken continuously on a daily basis. The contraceptive mechanism of the mini-pill is similar to that of combined oral contraceptives in some respects: altered, thickened cervical mucus is produced, and a progestational effect on the endometrium prevents implantation. However, ovulation is suppressed only 60% of the time, resulting in a higher failure rate than that seen with combined oral contraceptives (about 3 pregnancies/100 woman-years in younger women, compared with 0.3/100 woman-years in women over 40 years of age). It is estimated that one half of these pregnancies are due to user failure. Patients must be counselled to take the pill at the same time every day, and if a delay of 3 hours or more is encountered, a back-up method of contraception is advised for 48 hours.20 Irregular pill taking may also give rise to a higher than usual incidence of breakthrough bleeding.21

Despite these inconveniences, the progestin-only pill is the contraceptive method of choice for young breastfeeding mothers, in whom higher prolactin levels during lactation enhance the anti-ovulatory effect with resultant lower failure rates.20 These young women often begin coital activity prior to the first postpartum visit, when contraceptive counselling is traditionally begun. The progestin-only pill is approved for initiating at 6 weeks postpartum in patients who are only breastfeeding, and at 3 weeks after delivery in mothers who are nursing part-time or supplementing breastfeeding. These new FDA and package labeling indications are designed to reduce the unintended pregnancy rate in young women who may ovulate as early as 3 to 4 weeks after delivery, at a time when most either assume they are unable to conceive or before they have had a chance to resume their “usual” contraceptive methods.

The progestin-only pill is also useful persons who have medical conditions in which estrogen is either absolutely or theoretically contraindicated. In contrast with older age groups, these conditions are rare in adolescents but may include active thrombophlebitis or thromboembolic disease (unless on anticoagulation therapy) and severe systemic lupus erythematosus (due to the hypothetical increased risk of exacerbation of vascular disease). Additional contraindications to estrogen administration include uncontrolled diabetes mellitus with vascular complications (i.e. retinal changes and/or proteinuria) and active liver disease (due to the theoretical risk of an injured liver's inability to metabolize estrogen, leading to hypercoagulability).22 There may also be an advantage to minimizing or eliminating estrogen altogether when prescribing contraceptives for young women with classic migraine accompanied by focal neurologic complaints, to theoretically minimize the chance of microvascular thrombi forming in vulnerable areas.23

EMERGENCY POSTCOITAL CONTRACEPTION

Better known as the morning-after pill, the birth control pill as used for emergency postcoital contraception is the single most underutilized form of birth control in the United States today. It is not intended for routine use; rather, it is designed for use by a patient who has had unprotected sexual intercourse in the prior 72 hours. These women generally fall into two categories: those who have been victims of sexual assault (including date rape) and those whose usual method failed while attempting to practice responsible contraception (i.e. broken or leaking condom).

The original Yuzpe method consists of two 50-μg ethinyl estradiol/norgestrel pills taken as soon as possible within the 72-hour time frame, followed by two additional pills taken 12 hours later.24 Thirty- or thirty-five-microgram ethinyl estradiol pills combined with norgestrel or levonorgestrel may be used, but four must be ingested at each dose, for a total of eight pills.20 The principal mechanism of action appears to be prevention of nidation of a fertilized ovum; additional mechanisms may be inhibition of ovulation, detrimental effect on the corpus luteum with shortening of the luteal phase, or change in tubal transport time.25 No increase in ectopic pregnancy with use of the morning-after pill has been reported.26

Nausea occurs in 30% to 66% of patients26 but should not deter either clinician or user. An over-the-counter or prescription antiemetic is best taken prophylactically 1 hour prior to or simultaneous with dosing. Some experts recommend repeat dosing if emesis occurs less than 2 hours after ingestion of the oral contraceptive pills. Transient menstrual irregularities occur less frequently than do other side effects such as nausea and are not a major difficulty. Overall success rates average 75% and may be higher if the oral contraceptive pills are taken exactly as prescribed within the 72-hour window and if emesis does not occur. Patients must understand that the quoted 75% success rate does not imply a pregnancy rate of 25%, because other factors are in play (e.g. natural fecundity, timing in the cycle). Multiple recent reports suggest that the window of opportunity can be extended to 120 hours with reasonable success.25,27

Emergency postcoital contraception may be prescribed over the phone if time constraints exist. However, whenever possible the patient should present to her health care provider's office for a baseline pregnancy test and STD screening, especially in the case of sexual assault.

There is little basis for concerns over teratogenicity in cases in which an actual pregnancy results after pill ingestion. The major hindrance to prescribing the morning-after pill seems to be lack of awareness among the nongynecologic physician population and patients.28 All adolescents should be counselled regarding the widespread availability and safety profile of this underutilized method of pregnancy prevention.

LONG-ACTING HORMONAL METHODS

Depo-Provera

Depo-Provera, or 150 mg of depot medroxyprogesterone acetate (DMPA) administered intramuscularly, is becoming increasingly popular in the adolescent population. Advantages include lack of a need for daily compliance, interruption of foreplay, or cooperation of the male partner. However, it is still user-dependent in that it requires the patient to return to a health care professional's clinic for repeat injections every 12 weeks to ensure contraceptive efficacy. Although recommended dosing is every 3 months, its mechanism of action is suppression of ovulation, which does not occur for at least 14 weeks after the standard 150-mg injection.9

Menstrual cycle irregularities provoke the most concern regarding DMPA and may be the most common reason for premature discontinuation. Irregular bleeding and/or spotting occurs in as many as 25% to 50% of users in the first 6 to 12 months after initiation. Over time, however, this excessive vaginal bleeding may be circumvented by the administration of the usual 150-mg dose on a monthly basis during the first 3 months after initiation; by decreasing menometrorrhagia, compliance is increased. Alternatively, when persistent bleeding or spotting threaten to cause DMPA discontinuation, estrogen supplementation (e.g. 1.25 mg conjugated estrogen daily or its equivalent) usually reduces or eliminates any bleeding.

Most DMPA users become amenorrheic. Most teenagers find this to be a positive aspect of the drug, and the sooner oligomenorrhea or amenorrhea can be achieved, continuation rates improve by more than 50%.29 In patients with amenorrhea who present for reinjection more than 14 weeks after their previous dose, pregnancy should be excluded before the next dose is administered.

DMPA offers a unique advantage in certain handicapped adolescent patients, particularly those with seizure disorders. In addition to the advantages of oligomenorrhea or amenorrhea that a disadvantaged patient or their caretaker would appreciate, injectable medroxyprogesterone acetate has been shown to effect an increase in seizure threshold, thus resulting in a lowered seizure frequency. DMPA also provides improved contraceptive efficacy compared with estrogen-containing oral contraceptives in patients also taking antiseizure medications that induce hepatic enzymes, notably phenobarbital, phenytoin, and carbamazepine. Increased hepatic metabolism of the estrogen in oral contraceptives in these cases can lead to an increased failure rate.21 Reliable contraception is also particularly important in sociologically disadvantaged patients such as these, who may be partially or wholly institutionalized and hence at risk for sexual assault (molestation). Thus, the use of a method such as DMPA in these patients may have multiple benefits.

Norplant

Norplant is a sustained-release, subdermally placed progestin (levonorgestrel) contraceptive device consisting of six thin flexible capsules made of silastic rubber designed to remain in place for up to 5 years. Advantages include ease of continuance and lack of need for daily compliance, interruption of foreplay, or cooperation of the male partner.

Side-effects associated with use of Norplant include irregular bleeding or spotting, headaches, and acne.9,19 Various methods have been attempted to address irregular bleeding; the most successful of these has been short-term administration of oral low-dose estrogen (e.g. 1.25 mg of conjugated estrogen or 2 mg estradiol for 7 to 10 days).20

Due to its extremely efficient contraceptive effect (99%), most adolescents decide to continue with the Norplant method, particularly if counselled appropriately preinsertion.15,30 Continuation rates as high as 91% have been reported, with mean duration of use among adolescents of 26.5 months.31 However, if irregular menses, acne, hirsutism, or other signs of ovulatory dysfunction or androgen excess cause distress in Norplant users, another method such as a combined oral contraceptive pill may be a better choice. Removal of a Norplant device is best accomplished by a health care professional who is well trained in this procedure.

BARRIER METHODS

Male Condom

One-third of women age 18 to 19 years (and one half of all males this age) report having multiple partners in a 1-year period.32 This percentage decreases as women get older, and fortunately, condom use has increased in the United States among all women.33 Condoms and spermicides are the most commonly used nonhormonal contraceptive methods in teens aged 15 to 19 years.9 When used properly and correctly, they provide excellent, although not perfect, protection against pregnancy and STDs, including human immunodeficiency virus (HIV). Disadvantages include the need to interrupt foreplay and the requirement of the cooperation of the male partner; it is largely the male partner's unwillingness to consent to this method that results in its underutilization (Table 3).

TABLE 3. Reasons Given for Not Using Condoms

  Need to interrupt foreplay to apply
  Decreased penile and vaginal sensation during coitus
  Lack of availability if coitus unplanned or takes place in unusual location
  Ignorance regarding potential for pregnancy or transmission of sexually transmitted diseases
  Female partner's misplaced trust in promise of coitus interruptus
  Female partner's fear that request to use condom may result in male's rescindment of interest or affection
  Latex allergy

Susceptible individuals may experience symptoms of latex allergy with condom use. Fortunately, a polyurethane male condom is now available that is FDA approved for protection against pregnancy and should soon be approved for STD protection as well. Additionally, the polyurethane female condom (discussed later) is another useful alternative.

All adolescents using other forms of birth control should be reminded to also use condoms to prevent the risk of STD infection. It is worth reminding patients that a negative blood test for acquired immunodeficiency syndrome (AIDS) does not preclude the possibility of another STD being present, such as herpesvirus or human papillomavirus. Some health care providers recommend that condom-using women who become oral contraceptive users do not divulge their oral contraceptive use to their boyfriend so as to be less likely to be persuaded to stop using condoms. All condom users should also be made aware of the availability and safety of the morning-after pill (discussed previously) in case of a broken condom or a condom that leaks or slips off during withdrawal.

Female Condom

The female condom (Reality) is the only women-controlled device that protects against both unintended pregnancy and STDs, including HIV. It is a polyurethane sheath that is inserted into the vagina, with a flexible internal plastic ring that holds the top of the sheath near the apex of the vaginal vault. The sheath extends to partially cover the external genitalia. Effectiveness rates approach 97%.34 Disadvantages include its somewhat unusual appearance and the slight crackling sounds heard during coitus when used without a lubricant (now included in the packaging), both of which may be more discouraging to the adolescent than to the older patient. However, to highly motivated female adolescents, particularly those with a latex allergy or a less-than-fully-cooperative partner, it remains a viable alternative.

Diaphragm

As a relatively inexpensive form of birth control that affords some STD protection, the diaphragm can be a suitable option for a well-motivated teen in a stable relationship. It may disrupt foreplay to a lesser extent than condoms, although patients should be reminded that insertion of additional spermicide prior to each coital episode is required for optimal effectiveness (81%–98%), and the diaphragm must remain in place for 6 hours after sexual contact. However, the requirement for an initial fitting by a health care professional and the attendant cost may be a hindrance, and the bulky packaging makes it difficult to camouflage the device discreetly. Additionally, some teens may choose to ignore the recommendation for yearly replacement, which is another potential failure factor.

Cervical Cap

The cervical cap is similar to the diaphragm except that it covers only the cervix. For this reason, it is slightly more difficult to insert; many young patients are not dexterous enough or comfortable enough with their own anatomy to check high in the vagina for proper cervical coverage or cap dislodgement. Forgetting to fill the cap one-third full of spermicide or removing the cap less than 8 hours after coitus are other possible causes of user failure. Effectiveness varies from 88% to 94%7; thus, a back-up method of contraception is recommended for the first one to two cycles. The cervical cap is also associated with a theoretical risk of accelerated cervical dysplasia, and the cap is contraindicated in the presence of an abnormal Papanicolaou smear or lower genital tract infection. Although no cases have been reported, the cap carries the same potential risk of toxic shock syndrome as the diaphragm35 and should not be used during menstruation. All of these variables make the cervical cap a less than optimal choice for most teenagers.

Intra-uterine Device (IUD)

There are two IUDs currently available in the United States. The Progestasert is a progesterone-containing device approved for 1 year of use. The annual removal and reinsertion requirement limits the popularity of the Progestasert.

The Paragard is a copper-containing IUD approved for 10 years of use, a feature which greatly enhances its attractiveness. It is highly effective at preventing pregnancy, with success rates of 98% to 99%.36 Prior concerns about the IUD's mechanism of action being as an abortifacient have been put to rest; it is now known to work by interfering with viable sperm transport to the fallopian tube, thus preventing fertilization.37

Limiting IUD use to women at low risk for STDs has minimized or even eliminated the increased risk of pelvic inflammatory disease previously noted to accompany IUD insertion.38 Additionally, IUD use has not been found to compromise fertility.39

Despite these encouraging realizations, the recommended patient profile for the IUD precludes its use by most adolescents. Patients should be in a mutually monogamous relationship and have no history of pelvic inflammatory disease. Although many teenagers have no history of pelvic inflammatory disease and believe themselves to be in a mutually monogamous relationship, the inability to guarantee monogamy in a male partner of any age may present an obstacle to IUD use. The IUD may be appropriate for an adolescent mother who has been unsuccessful with other methods of contraception, but the decision to use it must be a mutual one made by the patient and her clinician on a highly individualized basis.

ENHANCING COMPLIANCE

All reversible methods of contraception must be used correctly and consistently if their contraceptive effect is to be maximized. Spending extra time for patient education on the first visit increases the likelihood that a return visit for continued services will follow. Patients should be encouraged to bring their parents or friends for moral support, and whenever possible, the male partner should be involved in the discussion of contraceptive options and benefits to enhance the couple's sense of mutual responsibility and maturity (Table 4).

TABLE 4. Enhancing Adolescent Contraceptive Compliance

  Remind patients that all interactions and records are confidential
  Educate patients about additional benefits of their method (e.g. less dysmenorrhea with oral contraceptives)
  Reassure patients regarding perceived side-effects of their chosen method (e.g. weight gain with oral contraceptives) even if patient does not inquire
  Encourage patients to call with questions or when needing prescription refills rather than discontinuing their method
  Provide samples of oral contraceptives, condoms, spermicide, and so on whenever possible
  Encourage concomitant condom use (latex type, with spermicide) to teens using other methods, on each visit
  Make teens aware of the availability and safety of the “morning-after pill” in cases of sexual assault, date rape, or contraceptive failure (e.g. broken condom)
  Encourage patients to bring along their male partner to office visits to increase their degree of involvement and sense of mutual responsibility

STERILIZATION

In certain cases of mentally retarded or severely physically handicapped young people, sterilization may be the best contraceptive option. This category would include drastic chronic disability without hope for significant improvement, in which the individual's capacity for self-care, learning, independent living, and economic self-sufficiency are limited.40 These patients are often partially or wholly institutionalized and consequently are at higher risk for sexual victimization than the average teenager. They lack the emotional maturity and cognitive ability to distinguish between appropriate and inappropriate physical contact and usually have been inadequately counselled regarding sexual intimacy. Accompanying physical disabilities add to their dependency on their caretakers, psychosocial isolation, and lack of access to preventive health care.

Many of these young girls also suffer from menometrorrhagia due to the oligo-ovulation that accompanies their chronic disease states, with subsequent difficulties with menstrual hygiene. Menses may also bring on an increased sense of frustration, especially in patients mentally incapable of understanding their physical condition. At times, this may be compounded by inappropriate behavior, combativeness, catamenial seizures, and other variations of premenstrual syndrome in the face of hormone fluctuations.

If it can be unequivocally decided that the patient suffers from a devastating mental and/or physical handicap that is irremediable and renders them forever incapable of successfully raising a child, sterilization is appropriate.

In most such cases, tubal ligation is the procedure of choice. If menstrual hygiene is an associated concern, endometrial ablation or hysterectomy (by laparoscopic approach whenever feasible) may be considered. When catamenial seizures or other premenstrual syndrome-type symptoms are unusually difficult to control, concomitant bilateral salpingo-oophorectomy with postoperative estrogen replacement has been recommended.

The tragic consequences of an undesired pregnancy in this special class of patients cannot be overstated and include inadequate prenatal care, potential inheritance of genetic or physical defects, possible congenital anomalies caused by medications, risks of maternal morbidity and mortality, and lack of serviceable child-rearing capabilities. By performing sterilization procedures in carefully considered circumstances, the rights of the individual are not being ignored; rather, they are being protected.

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