Anita L. Nelson
Lawrence S. Neinstein
Today, adolescence can last for up to a decade—the longest period in human history. Onset of puberty occurs much earlier in life and the assumption of adult roles is delayed until the 20s. During this decade, teens undergo tremendous physical and intellectual changes, and transfer from adult to peer group identification on their way to developing their own individual moral values and mature personal identities. An important element in this process is the emergence of sexual identity, behaviors, and attributes. Teens are profoundly affected by social conditions, peer pressures, and the media images, which when combined with their proclivity for experimentation and their sense of invulnerability, has resulted in risk-taking behaviors in all arenas, including reproductive health. Sexual activity, abortion, and birth rates among teens increased in the 1960s and 1970s, but those rates started to decline early in the 1990s, partially in response to the acquired immunodeficiency syndrome (AIDS) epidemic. Between 2001 and 2004, those rates were stable. Contraceptive use has increased dramatically to decrease adolescent pregnancy rates.
Despite this progress, significant adolescent sexual activity and risk-taking behaviors remain. The 2005 Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Survey found that 46.8% of high school students had had sexual intercourse during their lifetimes and 33.9% of students had sexual intercourse during the 3 months preceding the survey (Centers for Disease Control and Prevention, 2006). These rates are about the same as in 2003 and slightly higher than the ones reported in their 2001 survey. Prevalence of sexual activity was higher among male students than female students. Sexual debut can occur at an early age; 6.2% of students had sexual intercourse before age 13, although this percentage has declined since 1999. Quite naturally, sexual experience increases with age. Almost one third (29.3%) of 9th grade female adolescents had had intercourse; this rate rose to 62.4% for 12th grade female adolescents. Adolescents also tend to have multiple partners over time, generally in a series of monogamous relationships, 14.3% of high school students reported having had four or more partners in their lifetime (Centers for Disease Control and Prevention, 2006).
As concerning as these estimates are, it must be remembered that they underestimate adolescent sexual activity for several reasons. They exclude the sexual activity of teens who are not enrolled in school. To capture information about a broader sample of adolescents, data for 15- to 19-year olds is available from the 2002 National Survey of Family Growth (NSFG) (Mosher et al., 2005). In that survey, 26% of 15-year-old female adolescents had had sexual intercourse as had 77% of 18-year olds. Male adolescents reported lower rates (25% of 15 year olds; 62% of 18 year olds), which reflects the influence of older men having sex with adolescent females (Abma et al., 2004). Most 15- to 19-year olds (54.9% of men and 57.1% of women) had had at least one partner in the last year; more than 20% had had two or more partners.
In addition, many of the surveys do not ask about noncoital sexual practices, such as same-sex practices, heterosexual anal intercourse, or oral-genital sexual pleasuring. Although these practices do not result in pregnancy, they may expose the young person to sexually transmitted diseases (STDs) (see Chapters 60,61,62,63,64,65,66,67). Oral sex among teens aged 15 to 19 is more common than vaginal intercourse. Of the male and female adolescents aged 15 to 19 in the NSFG, 49% reported having vaginal intercourse, 55.1% reported heterosexual oral sex. More than one in five teens aged 15 to 19, who have not had vaginal intercourse, report that they have had oral sex. Fewer than 10% of teens report using a condom the last time they had oral sex. Interestingly, both males and females aged 15 to 17 reported receiving oral sex at higher rates (40.3% and 38%) than giving it (Mosher et al., 2005). Halpern-Felsher et al. (2005) demonstrated that oral sex is a reality among young adolescents, and that most of them do not believe that it is either dangerous to their health or inconsistent with their moral values. Heterosexual anal intercourse was reported by approximately 11% of teens. Same-sex sexual contact was reported by 4.5% of male teens and 10.6% of female teens (Mosher et al., 2005).
Additional insights into teen sexual activity are available from other surveys. The National Campaign to Prevent Teen Pregnancy reported that more than 1 in 10 young women who first had sexual intercourse before age 15 described it as nonvoluntary and many more described it as unwanted (Albert et al., 2003). A Kaiser Foundation survey of 15- to 17-year olds who had “had sex,” 51% said that
when they had sex for the first time, it was because they “met the right person,” 45% said it was because “the other person wanted to,” 32% said it was because they were “just curious,” 28% said it was because they “hoped it would make the relationship closer,” and 16% said it was because “many of their friends already had” (Sex Smarts, 2000). Cohen et al. (2002) reported that more than 70% of high school students said they had had sex in their parents' home or the home of their partner; more than half of acts occurred during week days. Pittman et al. (2005) reported that “doing nothing” was the immediate antecedent activity for sexual intercourse.
There was a 28% reduction in U.S. adolescent pregnancy rates between 1991 and 2004. Adolescent pregnancy rates are now the lowest they have been in the last 30 years. The elective abortion rate peaked in 1983 at 30.7/1,000 and steadily declined by more than half to 14.5/1,000 by 2000 (QuickStats, 2005). The birth rate in 15 to 19 old females declined 33% from its peak of 61.8/1,000 women in 1991 to 41.2/1,000 in 2004. Birth rates among younger teens 15 to 17 years of age declined the most and were 22.1/1,000, down by 42.7% from 1991 to 2004 (Hamilton et al., 2005). The NSFG data shows that the probability of a U.S. woman giving birth by age 20 is 13%. There are some other disturbing factors behind those numbers. Half of births to teen mothers involve men aged 20 to 24 and an additional one sixth of those fathers are older than 25 years (Males, 2004). The National Center for Health Statistics (NCHS) found that >80% of new adolescent mothers were unmarried in 2004 (Hamilton et al., 2005).
Despite the recent reduction in pregnancy-related rates, teen pregnancy rates in the United States are still much higher than those rates in other developed countries whose teens are generally as sexually active as their American counterparts (Darroch et al., 2001). Only the Russian Federation and Bulgaria have comparable pregnancy rates, but their teen birth rates are lower than in the United States. The primary difference in pregnancy rates is attributable to lack of contraceptive use by U.S. teens. Decreases in pregnancy rates are vitally important to the long-term well-being of teens. The impact of pregnancy on the teen can be ascertained by her actions and her attitudes. Estimates are that 78% of teen pregnancies are unintended (Abma et al., 2004), and 28% are electively terminated (Henshaw, 2004). Of those pregnancies that are continued to delivery, 57% are categorized by the young mother herself as mistakes, whereas only 22% of births are intended.
The recent decline in adolescent pregnancies is due both to decrease in sexual experience of adolescents (53% of decline) and to more effective contraception use (47% of decline) (Santelli et al., 2004). Between 1991 and 2001, the percentage of young women in high school who had ever had sexual intercourse declined from 51% to 43%, but it rose to 45.3% by 2003. Sexual activity among those who were sexually experienced did not change, but effective contraceptive use did. This is reflected in the fact that from 1991 to 2001, there was a notable decrease on the weight-average contraceptive failure rates (WACFRs) for teens. This decrease was due to a decline in the use of less effective methods such as withdrawal (which decreased from 20% to 13%) and no method (which decreased from 17% to 13%) and an increase in the use of condoms (from 40% to 51%) (Santelli et al., 2004). Other important changes are notable. Ever use of birth control pills increased from 52% to 61% between 1995 and 2002. Of women who had intercourse in the last 3 months, 83% reported using a method with their most recent episode (Abma et al. 2004). Injectable contraception use increased among sexually experienced women from 10% to 21% between 1995 and 2002. Importantly, dual method use (condom and hormonal method) more than doubled from 1995 to 2002 (8% to 20%) (Abma et al., 2004). However, these changes were not seen in every group. Among whites, there was no decrease in the WACFR, but the WACFR did decline from 1991 to 2001, by 20% among blacks, and by 24% among Hispanics (Santelli et al., 2004).
Condoms are the most popular method at first intercourse. Approximately 67% of women and 71% of men reported using this method with first coitus. However, 26% of 15- to 19-year olds still report not using any method with first coitus. Women who are older at sexual debut are more likely to report condom use at first intercourse than are younger women (Abma et al., 2004).
Contraceptive use patterns are complex. Analysis has shown that contraceptive use was more likely in female teens who had waited a longer time between the start of a relationship and first sex with that partner, had discussed contraception before first having sex, or used dual contraceptive methods. On the other hand, contraception was less likely to be used (or used consistently) if the women had taken a virginity pledge, had an older partner, had a number of close friends who knew her partner, or reportedly had a relationship that was not romantic but had those trappings (Manlove et al., 2003). Studies have shown that women who use contraception at first intercourse have significantly lower birth rates as teens, suggesting more consistent long-term teen use of contraception (Abma et al., 2004).
One interesting study asked public high school students where they would like to obtain information about contraception. Men were more likely than women to prefer receiving information from parents (23% versus 18%) and health education classes (16% versus 7.5%), whereas women were more likely than men to prefer a clinical setting (51% versus 27%) (Hacker et al., 2000). Understanding the differences in teen preferences can help providers meet the educational needs of adolescents. Also, appreciating the adverse impact that prior sexual abuse can have on the survivor's future use of contraception highlights the need to identify these women and provide special counseling (Saewyc et al., 2004).
One opportunity that is often overlooked in teaching adolescents is teaching their parents. Studies have shown that parent–teenager discussions where the parent was open, skilled, and comfortable with the discussion were associated with better teen-partner communications and ultimately better teen condom use. On the other hand, poor teen-parent discussions were negatively associated with condom use (Whitaker et al., 1999). This may be particularly important in one-parent households (Oman et al., 2005).
Since 1996, the Federal government has invested more than a billion dollars in abstinence-only, school-based programs, which has decreased access to comprehensive contraceptive information and services. Analysis of prototype abstinence-only programs developed in the earlier 1990s demonstrated no long-term beneficial impact (Kirby et al., 1997; Cagampang et al., 1997). Currently, no official analysis of the current federally funded programs has been reported, although the quality of these programs has been found to vary considerably (Wilson et al., 2005). According to the report “Abstinence Education Evaluation Phase 5 Technical Report” from the Texas Health Department, the number of adolescents who had had sexual intercourse did not change or actually increased after they had received abstinence-only education (Tanne, 2005).
A preliminary analysis of virginity pledge programs has been published. Despite the obvious influence on outcomes of selection bias (those who choose to pledge versus those who do not pledge), it has been reported that those who took pledges delayed their sexual debut by 12 to 18 months and married earlier. However, STD rates for virginity pledge-takers did not differ from nonpledgers, in part because pledge-takers were less likely to use condoms at sexual debut. In addition, pledgers were more likely to say that they had had oral or anal intercourse but not vaginal intercourse (Bruckner and Bearman, 2005). The all-or-nothing approach required by the abstinence-only programs may create barriers to knowledge and loss of protection for teens.
The list of contraceptive options available in the United States has both expanded and retracted over the last decade. Table 42.1 lists the currently available methods and those expected to be approved shortly. Oral contraceptive (OC) pills and condoms are still the most frequently used methods, but new hormonal delivery systems such as transdermal patches and vaginal rings have been
introduced to add convenience in use and, hopefully, to increase efficacy. The once-a-month combined hormonal injection was introduced but then removed from the market due to production problems and low sales.
Oral Contraceptive Pills
New pill formulations with lower doses of estrogen, different progestins, different pill utilization patterns, and new noncontraceptive benefits have been introduced. The first nonandrogenic progestin (drospirenone) is now available in two different formulations. More pills with lower doses of ethinyl estradiol (20 and 25 µg) are available. New patterns of utilization are also available. Three low-dose pill formulations reduce the number of placebo pills in their 28-day packet to minimize estrogen-withdrawal symptoms. Extended cycle use of pills with U.S. Food and Drug Administration (FDA)-approved products and off-label use of other pill formations, patches, and rings reduces the number of episodes of withdrawal bleeding women have each year. Although eliminating withdrawal bleeds offers significant health and quality-of-life benefits to female adolescents, careful counseling of teens is needed so that they can understand the safety of not bleeding with use of hormonal contraception use compared with the concerns that amenorrhea raises without hormone use. Each of these issues is discussed at greater length in Chapter 43.
Implants and Injectable Contraceptives
During the late 1990s, the implantable contraceptive system (Norplant-6) was withdrawn from the market. However, Implanon was approved by the FDA in July 2006. This is a single rod system, which greatly simplifies insertion and removal procedures. The injectable progestin-only method (depot medroxyprogesterone acetate [DMPA], Depo-Provera) made a significant contribution to teen contraception in the 1990s and early 2000s. A new formulation of DMPA with different buffers has been introduced with the name depo-subQ provera 104. This formulation reduces the injection dose from 150 mg to 104 mg while maintaining an intermediate term (12–14 weeks) efficacy and replacing intramuscular injections with subcutaneous shots. Subcutaneous injections offer the potential for self injection to streamline access. It is also approved for the treatment of symptomatic endometriosis. Concerns about the possible adverse effects that DMPA induced hypoestrogenemia may have on adolescent bone mineralization have prompted a new black box warning on both formulations. This is discussed at greater length in Chapter 47.
Changes in labeling for the copper intrauterine device (IUD) have made it a more attractive option for female adolescents. There is no longer a recommendation that the copper IUD candidate be parous or be in a stable, mutually monogamous relationship with no history of pelvic inflammatory disease (PID). The levonorgestrel IUD retains the more restrictive labeling, but offers candidates significant reduction in menstrual blood loss.
Male condoms have been greatly improved to encourage more consistent and successful utilization. The quality of condoms as a whole has increased in the last decade. Two polyurethane condoms are available for couples with latex allergy. New condom features such as ribs, scents, vibrating rings, different sizes, and different shapes have attempted to appeal to potential users. The snugger fit condom addresses the needs of younger men who have not completed all their secondary sexual growth. Extra large condoms with additional room at the tip have answered the needs of men who are well endowed. Simplified packaging, which eliminates the chance that the condom will be incorrectly unrolled, increases the chance that every use will be more successful. Spermicide coating has been removed from many condoms because the spermicide added no benefit for contraception or STD risk reduction, but it did increase cost. Condoms are now being marketed directly to women, which it is hoped will increase access. Adolescents should be told that condoms reduce the transmission of human immunodeficiency virus (HIV) and that correct and consistent use of condoms is a key component of safer sex practices.
Female Barrier Methods
Female barrier methods have also changed. Diaphragms may reemerge in the near future as a delivery system for microbicides. The female condom is available, but not as frequently utilized as the male condom because it is more expensive, more complicated to use, and less effective than the male condom. The latex cervical cap (Prentif Cervical Cap) is no longer available in the United States. However, the vaginal contraceptive sponge (Today), a cervical “shield” (Lea's Shield), and a silicone cervical cap (FemCap) have been introduced to be used with spermicide. See Chapter 45 on barrier methods.
Fertility Awareness Methods
Fertility awareness methods such as periodic abstinence and periodic use of contraception are less reliable for adolescents because of their irregular cycles. However, for women with well-established cycles lasting 26 to 32 days, the Standard Days Method with a ring of color-coded beads (“CycleBeads”) to help the couple identify at-risk days has greatly simplified the introduction and use of these methods. Other sexual practices, such as withdrawal, are quite prevalent with adolescents. If patients are going to rely on withdrawal, they should be carefully counseled on correct coital positioning and other techniques to make the method more effective as a contraceptive method.
One of the most important new products to be introduced in recent years is emergency contraceptives (ECs). The first FDA-approved EC, with estrogen and progestin (Preven), is no longer available. It has been replaced by the only other FDA-approved product (Plan B), a levonorgestrel only EC. Plan B is safe and can be used by virtually every adolescent female in need. There are only three contraindications—pregnancy, because there is no benefit (EC is not
an abortifacient); unexplained abnormal uterine bleeding (until pregnancy is ruled out); and allergies to any of the ingredients. EC provides a back-up in case the couple's primary method did not function or was not correctly used. Because EC works most effectively if taken as soon as possible after unprotected coitus, the optimal strategy is to provide EC by advance prescription. Advise the patient to fill the prescription and keep the product readily available (see Chapter 46). Plan B has been approved for behind-the-counter availability for people age 18 and over with government identification.
Selecting a Contraceptive Method
Age alone should not limit contraceptive choices for young individuals (Faculty of Family Planning and Reproductive Health Care Clinical Effectiveness Unit, 2004). Female adolescents need to be provided an overview of all methods of contraception. A brief description of how each method is used, how well it works to prevent pregnancy, what noncontraceptive benefits may accrue, and what side effects and health risks are possible with its use are necessary for informed consent and for long-term contraceptive continuation.
To help clinicians effectively counsel women and help them work with their patients to select optimal methods, the concept of “contraceptive fit” has been developed (Farrington, 2001). This approach recognizes that the best method for any one woman is the method with the greatest pregnancy protection that she will use consistently. There are four dimensions to the contraceptive fit model:
A patient's medical conditions may exclude some methods. For example, clinicians should not prescribe estrogen-containing methods to an adolescent woman with severe hypertension or breast cancer. Similarly, women taking medications that have significant drug–drug interactions with some contraceptives may not be offered those methods. Women with Chlamydia cervicitis are not IUD candidates.
This question helps providers establish the concept that pregnancy should be planned and prepared for and also helps highlight or diminish the attractiveness of long-acting methods. The typical use failure rates are helpful in identifying methods that best meet the patient's needs in this dimension.
Adolescent lifestyle can be quite hectic and certainly are the most variable of any age-group.
Episodic sexual activity patterns may discourage a woman from using methods that require daily administration, especially during weeks or months when she is not having coitus.
A young adolescent female may not be able to negotiate with her partner about sexual activities or the use of condoms (Stone and Ingham, 2002).
Although modifiable with education, this element may be the most critical one in the equation to ensure an adolescent's commitment to using her contraceptive method. Women who are concerned about using “synthetic hormones” or those who believe that pills make them gain weight will be far less likely to be successful OC users. Those women who recognize that the pills are responsible for the fact that their menses are less painful and more predictable are apt to be more consistent pill users. For female adolescents who rely strongly on their peers for advice, it is helpful to have teen success stories with which they can relate.
Important Properties of Contraceptives for Female Adolescents
Although female adolescents differ in their understanding of, commitment to, and need for contraception, there are some important features of different contraceptives that are particularly important for teen women.
It may be quite challenging for teens to use contraceptive methods correctly and consistently. Not only is sexual activity often unplanned and “spontaneous,” but it is also often episodic. Methods that require little forethought and/or preparation are most likely to be more successfully utilized. Injections, implants, and intrauterine contraceptives all share this property. Among the combined hormonal methods, the once-a-month contraceptive vaginal ring is most convenient, followed by the once-a-week patch. Teens, generally, more successfully utilize these longer acting methods than OC pills, which require daily dosing (Audet et al., 2001).
Adolescent utilization of contraceptives is generally less consistent than that of older women, but because adult utilization is so suboptimal, typical use failure rates for female adolescents are very similar to that of adults (Trussell, 2004) (Table 42.2). The discrepancies seen between the failure rate with correct and consistent use and the failure rates with typical use are greatest with methods that require action at the time of coitus (condoms) or regular administration (OCs). Since pregnancy prevention is very critical in this age-group, it is important to select methods with higher effective rates (IUDs, implants, and injections) and/or methods that may not be as inherently effective but are appealing to the teen (see following text). Mistakes do happen and passion does occasionally overwhelm good
judgment, so emergency contraception should be provided by advance prescription to every sexually active female adolescent and to each of those who may be contemplating sexual activity.
Sexually Transmitted Disease Risk Reduction
Adolescents are more likely to acquire STDs than other age-groups because of both their intrinsic biological vulnerability and their more risky sexual practices. Careful counseling about the risks attendant with the decision to become sexually active is an important element in providing contraceptive education. For adolescents who are sexually active, pregnancy protection should not be sacrificed for the sake of STD risk reduction. Adolescents who are at risk for pregnancy and for STDs should be offered methods to minimize each risk. The most effective method of contraception that she will use should be combined with male condoms (or to some extent, female condoms) to reduce the risk of many STDs, especially those transmitted by body fluids. Reassuring information has been presented indicating that none of the hormonal methods of contraception increases the risk of HIV infection (Morrison et al., 2005).
Maximize Noncontraceptive Benefits
Hormonal contraceptives can provide important health benefits and improve a young woman's quality of life in addition to providing birth control. Some birth control pills can be used to treat acne, reduce hirsutism, regulate menses (for those who want predictable bleeding), or
eliminate or minimize menses (for women who suffer from dysmenorrhea, catamenial seizures, menstrual migraine, premenstrual syndrome [PMS], or premenstrual dysphoric disorder [PMDD]). Hormonal contraceptives can also reduce menstrual blood loss, which may be particularly important to women with anemia or clotting disorders. Women with active lifestyles (athletes) and those with other hypoestrogenemic conditions (eating disorders) may benefit from both menstrual control and restoration of normal estrogen levels with potential beneficial effects on the skeleton. Women who have polycystic ovary syndrome (PCOS) benefit from the progestin in hormonal contraceptives to offset the unopposed estrogen exposure induced by their condition. All women benefit from long-term health improvement, such as the reduction in the risk of ovarian and endometrial cancers. New designs of condoms may enhance sexual pleasure as well as reduce the risk of acquiring and transmitting STDs.
Minimize Side Effects
The importance of side effects cannot be overstated. Foster et al. (2004) found that 9% of women in California who were at risk for unintended pregnancy used no method of contraception, mostly for method-related reasons, such as a concern about side effects. There are two strategies for reducing the impact that side effects have on contraceptive continuation rates. The first is to select a method with few side effects. The second is to counsel intensively about potential side effects before initiation and to respond promptly to any complaints of “nuisance” side effects, if they arise. In order to anticipate what side effects might cause an individual teen to stop using contraceptives, it is often instructive to ask her what problems she has heard about the method and what concerns she herself might have. Teens are very image conscious and generally live in the present. Therefore, if the patient notices any complexion changes or weight gain, she will often blame the contraceptive and discontinue its use. The need for adherence to a daily administration is more challenging for teens than it is for adults. Research has demonstrated the effectiveness targeted counseling can have on continuation rates. Working with a group of low-literacy Mexican women who were very worried about amenorrhea, Canto De Cetina et al. (2001) showed that structured counseling about the impact the injection had on menses decreased the discontinuation rates from 43% to 19%.
Flexibility in Contraceptive Initiation and Use
Beyond selecting a method with the adolescent, clinicians can enhance the young woman's success with the method by being flexible in its use. Each of the following Chapters (Chapters 43–47) gives more detailed examples of these practices, which although relatively new, have been shown to be safe and to reduce barriers to contraceptive use. The following principles and practices are especially important for teens:
Challenges Facing Clinicians
There are few issues in medicine that excite as much controversy as provision of contraceptive and reproductive health services to adolescents. In many jurisdictions, there are legal restrictions on the services that can be provided to the teen patient based only on the teen's request. Only 21 States and the District of Columbia explicitly allow all minors to consent for contraceptive services. Another 25 require prior pregnancy, high school graduation, parental consent, or other conditions (Guttmacher Institute, 2005). Even when there are no legal requirements for parental involvement, there is a challenge in many practices to preserve patient confidentiality in the face of inquiring parents, itemized billing, and indiscrete insurance companies.
The presence of the mother in the examination room may limit the clinician's access to complete information from her daughter. Regardless of whether or not a pelvic exam is needed that day, it is important to have a mother excused from the room for at least a few moments to permit private conversation with the patient.
Teens have short attention spans. A call from them or a request for an appointment requires immediate response. It can be challenging to arrange a busy office practice to accommodate these urgent calls. Having someone on staff who is sensitive to teen issues and capable of effectively communicating with them can be very valuable to a practice. American College of Obstetricians and Gynecologists (ACOG) has produced a script that can be used by staff to answer common adolescent-related
telephone questions (American College of Obstetricians and Gynecologists, 2003). When interacting with teens, reflective, open-ended questioning is more effective than direct, closed questions. Reflective questions, such as “If you had a friend who was thinking about having sex with her boyfriend, what would you want her to know?” can reveal much about your patient's knowledge base and attitude.
Clinicians have even greater challenges reaching young men with important contraceptive and STD risk-reducing messages and methods. Historically, the woman has been used as the proxy to carry condoms to the man. Although providing the young woman with barriers and supplies is unquestionably important (she is the one at risk for pregnancy), young men also need one-on-one education and medical counseling about their risks, responsibilities, and choices. Just more than one third of young men aged 18 to 19 reported that they had talked to a parent about contraception before they turned age 18 (Abma et al., 2004). Because many young men get no information at school or from their parents and may receive inaccurate information from their peers, access to medically accurate information may be only available in the confines of the medical office or as part of community outreach efforts in which medical professionals participate.
Challenges Facing Teens
Adolescent patients are confronted with several challenges in accessing contraceptive services. These barriers can be classified into the following groups of concerns:
Access to Low-Cost, Appropriate Medical Services
Adolescents often have limited financial resources. Even low-cost medical services can be prohibitively expensive for them. Lack of familiarity with large managed care systems can functionally limit access. Once in a system, teens must find providers to address their issues. Adolescents often wish to discuss issues of sexuality and contraception with their providers, but are reluctant to introduce the subjects when they are with their clinicians. This reluctance, together with the provider's hesitancy, results in a wide discrepancy between what teens want to discuss and what they do discuss with their primary health care physicians (Malus et al., 1987).
Access to Confidential Services
A randomized, controlled trial has clearly shown that teens are more willing to communicate with and seek health care from physicians who ensure confidentiality (Ford et al., 1997). Most (60%) teen women seeking sexual health services in one recent study reported that a parent or guardian was aware that they were in a family planning clinic. However, of the 40% of teens whose adult figures were not aware of their attending, more than 70% said they would not use the clinic for prescription contraception if parental notification were mandatory (Jones et al., 2005). The study also showed that lack of access to prescriptions would not reduce teen sexual activity, but would likely increase rates of adolescent pregnancies and STDs. Unfortunately, studies have shown that 17% to 37% of private physicians are unwilling to or do not provide reproductive health services to minors without parental consent (Jones et al., 2005), which may reflect state laws.
Access to Age-Appropriate Teen Services
Modern media profoundly affect adolescents' attitudes toward sex, as well as their communication and learning styles. Estimates are that the average teen witnesses 14,000 instances of sexual behavior on television each year, and that in <10% of those sexual encounters is there any mention of contraception or STDs. These exposures may not increase the accuracy of teens' understanding of sexuality and its risks, but they increase the teen's curiosity and expectations and may significantly influence behavior.
Television and videos have also transformed adolescent learning styles. Attention spans have been constricted to the 40-second sound bite. In the age of MTV, written handouts may have very limited educational benefit. If written materials are used, they must be corrected for age-appropriate literacy and for short reader attention spans. ACOG suggests that written materials be pocket sized. Furthermore, because some adolescents may not have confided to their parents that they are sexually active, written materials found in their possession might be incriminating. Videotapes or DVDs played in the office before the patient–provider interaction are quite helpful, as are individual counseling sessions with office staff trained in dealing with teens. Peer counselors are also effective adjuncts in outreach programs and in practice settings. Web sites can provide the teen more private and conveniently timed access to information.
Most adolescents do not get out of school until late in the afternoon, and they may have difficulty keeping appointments during the office hours of most practices. This may be particularly true if they have limited access to transportation and are trying to maintain privacy. Late afternoon or early evening office hours or weekend availability can enhance adolescent access to services. Privacy needs may also limit the times and ways in which the teen can interact with a health care provider. The adolescent who calls from a pay phone or cell phone to ask about a contraceptive side effect during her lunch break cannot be put on hold or called back later when the provider is between patients. One successful arrangement is to identify someone on the staff to answer such calls and then arrange the staff person's lunch hour around most teens' schedules.
Access to Broader Community-Based Programs
Each of the access issues listed previously is relevant at the individual provider level. To make even more impact on adolescent pregnancy rates and teenage sex activity, political, community, educational, and religious institutions require modification and involvement (Brindis, 1999). Demonstration projects have shown that broader, multicomponent, community-based programs are needed (Paine-Andrews et al., 1999). A comprehensive community-based program in South Carolina that involved media, local clergy, and schools and emphasized on decision making, communication skills, self-esteem enhancement, and human reproduction caused the pregnancy rates for 14- to 17-year-old adolescent females to fall
from 67 to 25 per 1,000 (Koo et al., 1994). After the removal of key providers and support elements of that program, the pregnancy rate rose again.
Other programs using peer counseling in schools and nurse practitioner counselors in off-campus sites have also been successful, but a coordinated effort that focuses on the root causes of teen sexuality and other risk-taking behaviors has even more leverage. Often girls have unprotected sex because of a secret desire to keep a boyfriend (by becoming pregnant), to have someone of her own to love, or to act out against a parent (Dodson, 1996).
The practitioner must be aware of whether his or her own office or clinic hours and setup are conducive to adolescent health care needs. In addition, the practitioner should become familiar with sources of referral for services such as contraception, STD treatment, and elective abortion. Finally, because virtually all studies show that parent–teenager communication is important to improving contraceptive use (Whitaker et al., 1999), clinicians (particularly pediatricians) can advise parents of small children about how to discuss sexuality issues with their children.
Contraceptive Considerations in Adolescents with Common Illnesses or Disabilities
As many as 10% to 20% of all children and adolescents experience illness or disability by age 20. The standard used to evaluate the safety of contraception in any individual situation is that the risks of using the method must be less than the risks presented by pregnancy. For women with serious medical problems, pregnancy may be very hazardous. Therefore, it may be reasonable to accept higher risks with birth control with these women than would be acceptable for healthier women. Some methods may be absolutely contraindicated in women. The appropriateness of use of any method must be evaluated considering how important pregnancy prevention is and what are the woman's other options.
The World Health Organization (WHO) Medical Eligibility Guidelines represent a consensus of contraceptive experts based on current research. The guidelines are not intended to be a basis for individual risk recommendations, but to provide national family planning organizations with recommendations upon which to base their protocols. Their recommendations are rated on a scale of 1 to 4 (Table 42.3).
It should be noted that the WHO rated category 1 (“no restriction on use”) includes all methods of reversible contraception for women with the following medical conditions—gestational diabetes, benign breast conditions, family history of breast cancer, varicose veins, nonmigraine headaches, benign ovarian tumors, past PID with subsequent pregnancy, viral hepatitis carrier, simple thyroid goiter, hypothyroidism, hyperthyroidism, pelvic tuberculosis, epilepsy, schistosomiasis (except with severe fibrosis of the liver), taking antibiotics (except rifampin or griseofulvin), more than 21 days after childbirth, or after first-trimester abortion. WHO rated as category 2 (“advantages generally outweigh theoretical or proven risks”) the use of estrogen-containing hormonal methods in the following situations—smoking at less than age 35, uncomplicated valvular heart disease, superficial thrombophlebitis, major surgery without prolonged immobilization, and breast-feeding 6 months or more after delivery. In these conditions, all other methods can be used without restriction (WHO category 1). Similarly, progestin-only pills carry a unique WHO 2 rating for past ectopic pregnancy and intrauterine contraceptives are uniquely identified as WHO 2 rating for past PID without subsequent pregnancy, vaginitis without cervicitis, uterine fibroids, thalassemia, anemia, nulliparity, severe dysmenorrhea, endometriosis, uterine abnormalities not disturbing cavity, and immediately following second-trimester abortion.
Initiating intrauterine contraceptives carries a WHO category 3 rating (theoretical or proven risks generally outweigh the advantages) for those with ovarian cancer, increased risk for STDs, HIV infection, AIDs, and benign trophoblastic disease. All other methods are rated WHO category 1 for this condition. The use of estrogen-containing hormonal methods is uniquely rated as WHO category 3 for nonbreast-feeding women less than 21 days postpartum or breast-feeding women between 6 weeks and 6 months postpartum, whereas all others are rated WHO category 1.
On the other hand, WHO rates as category 4 (“should not use”) estrogen-containing hormonal contraceptives for women who are having major surgery with prolonged immobility or leg surgery, but has no restriction on the use of all other methods (WHO category 1) in these situations. Use of intrauterine contraceptives is rated WHO category 4 while all other methods are rated as WHO category 1 in the following situations—current STDs or PID, distorted uterine cavity, pelvic tuberculosis, endometrial cancer, malignant trophoblastic disease, and immediately after septic abortion. Lactational amenorrhea was contraindicated (WHO category 4) with mood altering medications or other medications that are contraindicated for use in breast-feeding.
Conditions which involve considerations for more than one method are listed on Table 42.4. Additional conditions, which may be encountered in adolescent patients, are discussed subsequently.
All methods of contraception may be used by women with asthma. Historically, theoretical concern was raised about estrogen increasing mucus production and/or progesterone increasing mucus viscosity. However, clinical studies have failed to find any consistent association between OC use and the severity or frequency of asthma attacks. If theophylline is used in treatment of asthma, there can be notable drug–drug interactions. Both the estrogen and the theophylline levels may decrease and require higher dosing. It should be noted that current labeling of the levonorgestrel intrauterine system (LNG-IUS) recommends against its use in women who are immunosuppressed by chronic steroid use.
In a similar vein, the concern that exists with hormonal methods in individuals with cystic fibrosis involves the effect of progesterone on mucus. Progesterone causes thick cervical mucus, and this same effect could lead to thick bronchial mucus. A preliminary study Fitzpatrick et al. (1984) suggested that OCs containing <50 µg ethinyl estradiol doses may not exacerbate pulmonary disease. Stead et al. (1987) studied the pharmacokinetics
of sex steroids in women with cystic fibrosis using OCs and found that women with cystic fibrosis receive contraceptive protection similar to that achieved by healthy women. However, hormonal contraceptives should be used with extreme caution in teens with cystic fibrosis until further studies indicate that they are safe in such patients. If used, lower dose formulations would be preferred.
Inflammatory Bowel Disease
If disease is active and malabsorption of steroid sex hormone is possible, OC use is not appropriate (Faculty of Family Planning and Reproductive Health Care, Clinical Effectiveness Unit, 2003). Nonoral hormonal delivery systems (implants, injections, patches, and rings) bypass the enteric absorption problems and can, therefore, be used. In teens with stable, quiescent inflammatory bowel disease, OCs can be used with caution with close monitoring for possible impact on disease activity.
Adolescents with diabetes mellitus are a particularly important group. Fennoy (1989) found that they were at higher risk than expected to become pregnant at a time when their glucose control was often at its worst. Adolescents are also less likely to have developed vascular complications than older diabetic patients and may be the best candidates to use low-dose hormonal methods. Implants may be attractive because of their limited impact on glucose and lipid profiles. Progestin injections have more notably deleterious effects on glucose control and lipid profiles, necessitating careful consideration of benefits and risks. All women with diabetes using hormonal methods of birth control require ongoing glucose monitoring. They also need counseling to plan and prepare for any pregnancies, because preconceptional glucose control has profound impact on pregnancy outcomes.
Iron Deficiency Anemia
Hormonal methods of birth control can be helpful for patients with iron deficiency anemia because they tend to limit menstrual flow. Long-term use of progestin injections and LNG-IUS usually results in amenorrhea, which is extremely attractive to patients with anemia. Extended cycle with combined hormone methods reduces menstrual blood loss.
Initiation of copper-bearing IUDs should be discouraged in the face of severe anemia.
Hormonal methods of birth control are excellent choices for patients with hemorrhagic disorders that are intrinsic or medication induced. Hormonal contraceptives tend to diminish the menorrhagia experienced by many women with coagulation disorders by limiting or eliminating menstrual flow (Neinstein, 1994). Combination hormonal contraceptives, as well as progestin injections also suppress ovulation and decrease the ever-present risk of hemorrhage with extrusion of the follicle.
Psychiatric Disease and Mental Retardation
Adolescents with psychiatric conditions frequently have their family planning needs overlooked. Sometimes, their sexuality is seen as acting out or a manifestation of their underlying disease. Once recognized as having contraceptive needs, these patients may have difficulty in providing informed consent or in effectively using a contraceptive method. Many mentally ill patients have dual diagnoses, such as substance abuse and mental illness (often depression) or epilepsy. Barrier methods provide needed reduction in the risk of acquiring an STD, but they may not be consistently used. IUDs are often not appropriate because these patients can be at high risk for PID. Hormonal methods may be preferable with the following caveats:
Mentally retarded adolescents also require special considerations because often they are quite curious and uninhibited. Many are vulnerable to exploitation. Sex education is often neglected in these patients. The provider faces both legal questions and practical problems in trying to assess patients' understanding of methods and their ability to apply the selected method effectively. Mental retardation, by itself, usually does not constitute a medical contraindication to use of hormonal contraceptives, but studies show that long-term compliance with OCs in noncontrolled environments is very low. In one study of mentally retarded female adolescents (Chamberlain et al., 1984), the 1-year continuation rate with OCs was only 32%. Satisfaction was highest with injectable contraception. Implants require patient cooperation for insertion and removal under local anesthesia; severely retarded patients may not be able to comply. Injections offer effective intermediate-term contraception, and the progestin injections usually offer the additional benefit of ultimate amenorrhea. Barrier methods and natural family planning (NFP) have no adverse effects on women who are mentally retarded, but the severely impaired patient may not be capable of understanding how to use the methods.
Connective Tissue Disease
Systemic Lupus Erythematosus
Systemic lupus erythematosus (SLE) has been closely related to hormones. The strong bias in the female-to-male ratio and the relative frequency of flares during pregnancy raise concerns for the use of estrogen-containing hormonal contraceptives. Two recent studies suggested that the incidence of adverse events were similar among women with SLE, irrespective of the type of contraceptive they were using (Sanchez-Guerrero et al., 2005), and that OCs do not increase the risk of flare among women with SLE whose disease was stable (Petri et al., 2005). It would appear reasonable to consider the use of combined OCs for those women with inactive or moderately active, stable disease. Progestin-only methods appear safe in most women with lupus; in studies to date, there have been no significant differences in numbers of episodes of active SLE flares in progestin users versus controls. Labeling for the LNG-IUS indicates that its use is not recommended if the SLE patient is immunocompromised by her condition or by corticosteroid use, but copper-bearing IUDs are allowed. Barrier methods have the least number of side effects and offer STD risk reduction; however, they have high failure rates, and pregnancy can pose serious hazards to the woman with SLE. NFP similarly has no direct adverse effects but is associated with significantly higher failure rates.
Hormonal contraceptive methods are excellent choices for women with rheumatoid arthritis. Some studies have suggested that OCs may reduce the risk of developing this disease, but there is little evidence they reduce the severity of preexisting disease. Copper IUDs may be used by affected women who are able to check monthly for strings, but the LNG-IUS may not be appropriate for those using steroids or other immunosuppressive therapy. Barrier methods are not contraindicated, but female barrier methods may not be appropriate for women with severe disabilities of their hands and hips.
Most adolescents with chronic renal failure are infertile due to hypothalamic-pituitary dysfunction. During dialysis therapy, however, some women resume normal ovulatory function. For sexually active adolescents with menstrual function, contraception is an important issue. The major contraindications to OC use in these adolescents are hypertension and thromboembolic problems. Serum concentrations of progestin from injections in patients undergoing hemodialysis are maintained within therapeutic levels. Intrauterine contraceptive may be contraindicated either because of anemia and/or immunocompromise associated with renal failure. Barrier methods are not contraindicated, but may be associated with unacceptably high failure rates. NFP methods are difficult to use in the face of irregular menstruation.
Ovulation and fertility often return within 6 months of successful renal transplantation. Information regarding OC use in an adolescent with a renal transplant is very limited. In teens with no significant hypertension, low-dose, estrogen-containing methods could be used with extreme caution. Progestin-only methods are good choices, except the LNG-IUS because the women are immunosuppressed to prevent graft rejection. Other methods may be used as outlined earlier.
Comprehensive contraceptive education is the healthiest approach to providing reproductive health care to adolescents. Recognizing that human beings are sexual beings is the starting point for cultivating a long-term commitment to sexual health in adolescents. Encouraging abstinence is one important message, but helping teens assume responsible adult roles in protecting themselves and their partner's current health and well-being as well as their fertility is also important. Parents benefit if they can learn accurate information and skills in order to feel comfortable when discussing this important dimension of human life with their children. Health care providers can work directly with adolescents to provide them all the information they need; they can work through the parents to help families and they can work in their communities to advocate adolescent rights to accurate information and reproductive health services.
For Teenagers and Parents
http://www.engenderhealth.org. Engender Health International site with basic information on contraception.
http://www.itsyoursexlife.com/. Henry J. Kaiser Family Foundation site provides sexual health information for young adults and their parents.
http://www.sxetc.org/. This online teen newsletter examines love, sex, relationships, and health.
http://www.teenwire.com/. This teen site from the Planned Parenthood Federation of America provides information and news about teen sexuality, sexual health, and relationships.
http://www.youngwomenshealth.org/. The Center for Young Women's Health site, sponsored by Children's Hospital in Boston, provides information on health issues that affect teenage girls and young women.
http://www.reproline.jhu.edu/english/1fp/1methods/1methods.htm. Reproductive Health Online: On methods.
http://www.reproline.jhu.edu/english/1fp/1special/1special.htm. Reproductive Health Online: On special circumstances.
For Health Professionals
http://www.acog.org/. Information and resources from the American College of Obstetricians and Gynecologists.
http://www.agi-usa.org/index.html. Information and resources from the Alan Guttmacher Institute, a nonprofit organization focused on reproductive health research, policy analysis, and public education.
http://www.arhp.org/. Information and resources from the Association of Reproductive Health Professionals, an interdisciplinary organization that fosters research and advocacy to promote reproductive health.
http://www.conrad.org/. Contraceptive Research and Development Program site provides general information on birth control methods, updates on ongoing research projects, and provides information on contraceptive technology workshops.
http://www.fhi.org/. Family Health International's site provides information on AIDS/HIV, STDs, family planning, reproductive health, and women's studies.
http://www.kff.org/. Henry J. Kaiser Family Foundation site provides information on Adolescent Sexual Health.
http://www.ncbi.nlm.nih.gov/PubMed/. National Library of Medicine search service to access the 9 million citations in MEDLINE and other related databases, with links to participating online journals.
http://www.reproline.jhu.edu/. The Reproductive Health Online site, which is based at The Johns Hopkins University, provides information on family planning and selected reproductive health issues.
http://www.teenpregnancy.org. The National Campaign to Prevent Teen Pregnancy provides comprehensive information about teen pregnancy rates as well as public policy and programmatic recommendations.
References and Additional Readings
Abma JC, Martinez GM, Mosher WD, et al. Teenagers in the United States: sexual activity, contraceptive use, and childbearing, 2002. Vital Health Stat 23 2004;(24):1.
Albert B, Brown S, Flanigan C, eds. 14 and younger: the sexual behavior of young adolescents. Washington, DC: National Campaign to Prevent Teen Pregnancy, 2003.
American College of Obstetricians and Gynecologists. Tool kit for teen care: suggested responses to common adolescent-related telephone questions. Washington, DC: American College of Obstetricians and Gynecologists, 2003.
Audet MC, Moreau M, Koltun WD, et al. ORTHO EVRA/EVRA 004 Study Group. Evaluation of contraceptive efficacy and cycle control of a transdermal contraceptive patch vs. an oral contraceptive: a randomized controlled trial. JAMA 2001;285(18):2347.
Bermas BL. Oral contraceptives in systemic lupus erythematosus—a tough pill to swallow? N Engl J Med 2005;353:2602.
Brindis C. Building for the future: adolescent pregnancy prevention. J Am Med Womens Assoc 1999;54:129.
Bruckner H, Bearman P. After the promise: the STD consequences of adolescent virginity pledges. J Adolesc Health 2005;36(4):271.
Cagampang HH, Barth RP, Korpi M, et al. Education now and babies later (ENABL): life history of a campaign to postpone sexual involvement. Fam Plann Perspect. 1997;29(3):109.
Canto De Cetina TE, Canto P, Ordonez Luna M. Effect of counseling to improve compliance in Mexican women receiving depot-medroxyprogesterone acetate. Contraception2001;63(3):143.
Centers for Disease Control and Prevention. Youth risk behavior surveillance, United States, 2005. Surveillance Summaries June 9, 2006. MMWR Morb Mortal Wkly Report; 2006;55(SS-5).
Chamberlain A, Rauh J, Passer A, et al. Issues in fertility control for mentally retarded female adolescents. I. Sexual activity, sexual abuse, and contraception. Pediatrics1984;73(4):445.
Cohen DA, Farley TA, Taylor SN, et al. When and where do youths have sex? The potential role of adult supervision. Pediatrics 2002;110(6):e66.
Darroch JE, Singh S, Frost JJ. Differences in teenage pregnancy rates among five developed countries: the roles of sexual activity and contraceptive use. Fam Plann Perspect2001;33(6):244.
Dodson L. We could be your daughters. Cambridge, MA: Radcliffe Public Policy Institute, 1996.
Faculty of Family Planning and Reproductive Health Care, Clinical Effectiveness Unit. FFPRHC guidance (October 2003): first prescription of combined oral contraception. J Fam Plann Reprod Health Care 2003;29(4):209.
Faculty of Family Planning and Reproductive Health Care Clinical Effectiveness Unit. FFPRHC guidance (October 2004) contraceptive choices for young people. J Fam Plann Reprod Health Care 2004;30(4):237; quiz 251.
Farrington A. Today's contraceptive options: finding the right fit. Health Sex 2001;6(3):4. Accessed 11/27/05 at http://www.arhp.org/files/H&Sndic2001.pdf.
Fennoy I. Contraception and the adolescent diabetic. Health Educ. 1989;20:21.
Fitzpatrick SB, Stokes DC, Rosenstein BJ, et al. Use of oral contraceptives in women with cystic fibrosis. Chest 1984;86(6):863.
Ford CA, Millstein SG, Halpern-Felsher BL, et al. Influence of physician confidentiality assurances on adolescents' willingness to disclose information and seek future health care. A randomized controlled trial. JAMA 1997;278(12):1029.
Foster DG, Bley J, Mikanda J, et al. Contraceptive use and risk of unintended pregnancy in California. Contraception 2004;70(1):31.
Grunbaum JA, Kann L, Kinchen S, et al. Youth risk behavior surveillance–United States, 2003. MMWR Surveill Summ 2004;53(2):1.
Guttmacher Institute. Minors' access to contraceptive services as of November 1, 2005. State policies in brief. New York: Guttmacher Institute, Accessed 11/27/05 at http://www.agi-usa.org/statecenter/spibs/spib_MACS.pdf. 2005.
Hacker KA, Amare Y, Strunk N, et al. Listening to youth: teen perspectives on pregnancy prevention. J Adolesc Health 2000;26(4):279.
Halpern-Felsher BL, Cornell JL, Kropp RY, Oral versus vaginal sex among adolescents: perceptions, attitudes, and behavior. Pediatrics 2005;115(4):845.
Hamilton BE, Ventura SJ, Martin JA, et al. Preliminary births for 2004. Health E-Stats. National Center for Health Statistics. Released October 28, 2005. Accessed 11/27/05 at http://www.cdc.gov/nchs/products/pubs/pubd/hestats/prelim_births/prelim_births04.htm. 2005.
Henshaw SK. U.S. teenage pregnancy statistics with comparative statistics for women aged 20–24. New York: Guttmacher Institute, Accessed 11/27/05 at http://www.agi-usa.org/pubs/teen_stats.html. 2004.
Jones RK, Purcell A, Singh S, et al. Adolescents' reports of parental knowledge of adolescents' use of sexual health services and their reactions to mandated parental notification for prescription contraception. JAMA 2005;293(3):340.
Kirby D, Korpi M, Barth RP, et al. The impact of the postponing sexual involvement curriculum among youths in California. Fam Plann Perspect 1997;29(3):100.
Koo HP, Dunterman GH, George C, et al. Reducing adolescent pregnancy through a school- and community-based intervention: Denmore SC, revisited. Fam Plann Perspect1994;26:206.
Males M. Teens and older partners. ReCAPP. 2004 May-June. Accessed 11/27/05 at http://www.etr.org/recapp/research/AuthoredPapOlderPrtnrs0504.htm. 2005.
Malus M, LaChance PA, Lamy L, et al. Priorities in adolescent health care: the teenager's viewpoint. J Fam Pract 1987;25(2):159.
Manlove J, Ryan S, Franzetta K. Patterns of contraceptive use within teenagers' first sexual relationships. Perspect Sex Reprod Health 2003;35(6):246.
Morrison CS, Richardson BA, Celentano DD, et al. Prospective clinical trials designed to assess the use of hormonal contraceptives and risk of HIV acquisition. J Acquir Immune Defic Syndr 2005;38(Suppl 1):S17.
Mosher WD, Chandra A, Jones J. Sexual behavior and selected health measures: men and women 15–44 years of age, United States, 2002. Adv Data 2005;15;(362):1.
Neinstein LS. Issues in reproductive management. New York: Thieme Medical Publishers, 1994.
Oman RF, Vesely SF, Aspy CB. Youth assets and sexual risk behavior: the importance of assets for youth residing in one-parent households. Perspect Sex Reprod Health2005;37(1):25.
Paine-Andrews A, Harris KJ, Fisher JL, et al. Effects of a replication of a multicomponent model for preventing adolescent pregnancy in three Kansas communities. Fam Plann Perspect 1999;31(4):182.
Petri M, Kim MY, Kalunian KC, et al. Combined oral contraceptives in women with systemic lupus erythematosus. N Engl J Med 2005;353:2550.
Pittman S, Tita AT, Barratt MS, et al. Seasonality and immediate antecedents of sexual intercourse in adolescents. J Reprod Med 2005;50(3):193.
QuickStats from the National Center for Health Statistics. Pregnancy, birth and abortion rates for teenagers aged 15–17 years—United States, 1976–2003. JAMA 2005;293:1722.
Saewyc EM, Magee LL, Pettingell SE. Teenage pregnancy and associated risk behaviors among sexually abused adolescents. Perspect Sex Reprod Health 2004;36(3):98.
Sanchez-Guerrero J, Uribe AG, Jimenez-Santana L, et al. A trial of contraceptive methods in women with systemic lupus erythematosus. N Engl J Med 2005;353:2539.
Santelli JS, Abma J, Ventura S, et al. Can changes in sexual behaviors among high school students explain the decline in teen pregnancy rates in the 1990s? J Adolesc Health2004;35(2):80.
Forman G. Sex smarts: decision making. Menlo Park, CA: Henry Kaiser Family Foundation and Seventeen Magazine, September 2000.
Smith BL, Martin JA, Ventura SJ. Births and deaths: preliminary data for July 1997–June 1998. Natl Vital Stat Rep 1999;47:1.
Stead RJ, Grimmer SF, Rogers SM, et al. Pharmacokinetics of contraceptive steroids in patients with cystic fibrosis. Thorax 1987;42(1):59.
Stone N, Ingham R. Factors affecting British teenagers' contraceptive use at first intercourse: the importance of partner communication. Perspect Sex Reprod Health2002;34(4):191.
Tanne JH. Abstinence only programmes do not change sexual behaviour, Texas study shows. Br Med J 2005;330(7487):326.
Trussell J. The essentials of contraception: efficacy, safety and personal considerations. In: Hatcher RA, Trussell J, Stewart F, et al. Contraceptive technology, 18th ed. New York: Ardent Media, 2004:226.
Whitaker DJ, Miller KS, May DC, et al. Teenage partners' communication about sexual risk and condom use: the importance of parent-teenager discussions. Fam Plann Perspect1999;31(3):117.
Wilson KL, Goodson P, Pruitt BE, et al. A review of 21 curricula for abstinence-only-until-marriage programs. J Sch Health 2005;75(3):90.
Zabin LS, Emerson MR, Ringers PA, et al. Adolescents with negative pregnancy test results. An accessible at-risk group. JAMA 1996;275(2):113.