Many health professionals are concerned that American teens are particularly at risk for becoming infected with HIV, the virus that causes AIDS (Trepka et al., 2008). Var­ious surveys have shown that most adolescents in the United States are familiar with the basic facts about AIDS and are aware that high-risk activities can lead to transmis­sion of HIV. Unfortunately, even though most teens know the basic facts about HIV/ AIDS, this knowledge has not resulted in behavior changes in many teenagers. Several studies of high-school-age and college-age youths suggest that because most teenagers do not believe that they are at risk for contracting HIV, most do not significantly alter their sexual behavior to avoid infection (Feroli & Burstein, 2003; Trepka et al., 2008).

The notion of the "personal fable" (Elkind, 1967) is relevant to a consideration of adolescent risk taking and sexual behavior. Adolescents are particularly susceptible to a kind of cognitive egocentrism, an illusionary belief pattern in which they view them­selves as somehow invulnerable and immune to the consequences of dangerous and risky behavior (Feroli & Burstein, 2003). Thus many adolescents continue to engage in high-risk sexual behaviors, not because they are ignorant about HIV/AIDS and other STIs but because they falsely view themselves as being at very low (or no) risk of suffer­ing negative consequences (Feroli & Burstein, 2003). Also, research suggests that having a friend who engages in unprotected sexual intercourse increases the likelihood that a teenager will also engage in unprotected intercourse (Kim et al., 2011).

Behaviors that put young people at risk for HIV infection include engaging in inter­course without condoms; using alcohol, cocaine, and other drugs that impair judgment, reduce impulse control, and thus increase the likelihood of hazardous sexual activity; sharing needles with other intravenous drug users; exposing themselves to multiple sex­ual partners; and choosing sexual partners indiscriminately (Dariotis et al., 2011; Gross- bard et al., 2007; Trepka et al., 2008). The continuing trend toward a younger age of first intercourse is disturbing because people who begin sexual activity by age 15 tend to have significantly more lifetime sexual partners than those who begin having sexual inter­course at an older age (Cheng & Landale, 2011). (Exposure to multiple sexual partners is a high-risk sexual behavior, as discussed in Chapter 15.) Furthermore, young adolescent females who have their initial sexual experiences with older male partners are more likely to engage in unprotected, risky sexual behavior in adulthood (Senn et al., 2011).

With the growing awareness that teenage women are at risk for HIV infection (and other STIs), most family clinic counselors now encourage clients, even those on birth control pills, to regularly use condoms to protect themselves against STIs. Unfortunately, this advice is often unheeded, for a variety of reasons. Many young women and their part­ners are unwilling to deal with the minor inconvenience of condoms when they believe that they are already adequately protected from an unwanted pregnancy (Ott et al., 2002;

U. S. Congress Considering Measures to Reduce Teen Pregnancy Prevention Programs

Zimmerman et al., 2007). A study of 436 sexually active adolescents found that con­dom use among teenagers who used birth control pills was much lower than condom use among adolescents who did not use oral contraceptives (Ott et al., 2002).