The United States has the highest teenage pregnancy rate of any developed nation, with nearly one million teenage pregnancies each year (Jones et al., 1985). Adolescent childbearing has become a prominent social issue because of the broad social and economic consequences. In addition, since the advent of the AIDS epidemic, concern about sexual risk-taking has gone beyond the problem of unintended pregnancy (Hein, 1993). Although the number of AIDS cases diagnosed among teenagers is currently small - one percent of the reported cases - the mean latency of 11 years from HIV infection to AIDS has kept the manifest disease hidden; most people infected as teenagers do not become ill with AIDS-defining illness until their 20s. Adolescent AIDS cases have increased 77% in the past two years (House Select Committee on Children, Youth and Families, 1992) and the proportion of adolescent girls who have become infected with HIV is "worringly high" (Ehrhardt, 1992). Moreover, rates of other sexually transmitted diseases are higher among sexually active teenagers than they are among adults (Cates, 1990).
The well-documented negative health, social, and economic consequences associated with adolescent fertility, have made the prevention of teenage pregnancy a public health priority. In 1987, the National Academy of Sciences (NAS) published a report pointing out that the sexual decision-making process undergone by young women involves a sequence of choices. The first stage in the sequence of options is the decision to be sexually active and engage in sexual intercourse. Any sexual activity that brings a person in contact with semen, blood, or vaginal secretions of a person infected with HIV places that person at risk for infection (Goedert, 1987). Because early initiation of sexual intercourse lengthens the period of risk for teenage pregnancy as well as STD and HIV infection, there is a need to more clearly understand the factors associated with an adolescent's likelihood of engaging in sexual intercourse. The identification of such factors could contribute to the development of programs to prevent or modify risky sexual behaviors.
It is not surprising, therefore, that numerous studies have examined antecedents of early sexual intercourse (for a summary see Dryfoos, 1990). These studies have identified a number of categories of variables associated with sexual intercourse among adolescents including demographic, personal, interpersonal or normative influences, and problem behaviors. There is growing evidence that adolescent problem behaviors are intercorrelated (Donovan & Jessor, 1985; Mott & Haurin, 1988; Osgood, Johnston, O'Malley, & Backman, 1988). While some studies have shown that the frequency of sexual intercourse is associated with other behaviors such as delinquent acts and substance use (Biglan et al., 1990; Donovan & Jessor, 1985; Mott & Haurin, 1988), in a longitudinal study Chewning (1988) found that high-risk health practices and problem behaviors were associated with early onset of sexual intercourse.
Many of the previous studies have focused on only one or two categories of variables; fewer studies have investigated the simultaneous relationship of different categories of variables to engaging in sexual intercourse. A major limitation of this narrow focus is that the relative predictive power of different categories of variables cannot be determined. In addition, because the burden of unwanted pregnancy falls disproportionately on women, the majority of research has focused on attributes of females rather than of males. However, sexual behavior occurs in the context of dyadic interaction.
The purpose of this study was, therefore, to examine the multiple factors associated with engaging in sexual intercourse among a sample of female and male adolescents. Based on previous research findings and theoretical models, three broad categories of variables were hypothesized to be associated with sexual behavior: (1) demographic characteristics; (2) personal variables; and (3) problem and/or risk-taking behaviors. …