Copyright 1998 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.1998
To determine whether gender-specific patterns of risk behaviors are associated with a self-reported history of ever having been forced or pressured to have sexual intercourse among sexually active adolescents.
Subjects and Methods
In 1995, 21297 eighth- through 12th-grade students in 79 public and private schools in Vermont were anonymously surveyed. Data were analyzed for 7884 sexually active students (3931 girls and 3953 boys). Demographic variables and indicators of violence, suicide, recent substance use, sexual behavior, pregnancy, and weight control behavior were assessed. Data were analyzed with multiple logistic regression.
Of the sexually active students, 30.3% of the girls and 9.9% of the boys reported ever being forced or pressured to have sexual intercourse. Among sexually active girls, being in 1 or more physical fights in the past year (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.40-1.94), seriously considering suicide (OR, 1.97; CI, 1.69-2.31), more years of sexual activity (OR, 1.52; CI, 1.43-1.61), not using a condom at last sexual intercourse (OR, 1.28; CI, 1.09-1.49), and having been pregnant more often (OR, 1.40; CI, 1.16-1.69) were associated with having been forced or pressured to have sex. For sexually active boys, seriously considering suicide (OR, 1.64; CI, 1.23-2.20), more years of sexual activity (OR, 1.21; CI, 1.12-1.31), more male partners in the past 3 months (OR, 1.30; CI, 1.14-1.48), more female partners in the past 3 months (OR, 1.09; CI, 1.01-1.18), not using a condom at last sexual intercourse (OR, 1.37; CI, 1.03-1.82), having been involved in more pregnancies (OR, 1.64; CI, 1.29-2.08), and having vomited or used laxatives (OR, 3.44; CI, 2.18-5.43) were associated with having been forced or pressured to have sex.
Patterns of risk behaviors differed among sexually active male and female adolescents reporting being forced or pressured to have sex. Having been forced or pressured to have sex was associated with externalizing behavior, such as fighting, among girls and with internalizing behavior, such as bulimia, among boys. These unexpected associations have notable implications for screening adolescents for a history of having been forced or pressured to have sex.
NONVOLUNTARY or coercive sexual intercourse has been reported by 7% to 17% of adolescents and young adults in studies in the United States.1- 9 Approximately 20% of adult women and 5% to 10% of adult men report sexual abuse at some time during their childhood and adolescence.10 Date rape has been reported by 5% to 28% of college women2,11,12; one study has suggested that 22% of a sample of men at one college had experienced coercive sexual experiences since the age of 16 years.13
Unwanted sexual activity during childhood and adolescence has been associated with several psychological symptoms, including low self-esteem,14,15 depressed mood,3,16,17 and suicidal ideation or attempts.3- 8,18 Adolescents who report unwanted sexual experiences are more likely to report frequent alcohol and other drug use.3,5,7,19 In addition to substance abuse, the desire to avoid memories and feelings associated with the abuse may lead to suicidal ideation, dissociation, and tension-relieving activities like self-mutilation and bingeing or purging.20 While some studies suggest a relationship between sexual abuse and eating disorders,21- 23 others have found no association.24- 26 A history of sexual abuse or rape has been associated with current unsafe sexual practices and human immunodeficiency virus risk-taking behaviors among urban youths.27 Girls who have been sexually abused are more likely to engage in early voluntary intercourse and have sexual intercourse more frequently than nonabused girls.28
Childhood sexual experience among girls involving intercourse, occurring more than once, beginning after puberty, and involving a family member is associated with particularly notable psychological symptoms.9,29 In addition, sexual abuse that is accompanied by force, involves a male perpetrator who is an adult (particularly the father or stepfather), and is not followed by a supportive familial response when disclosed is associated with a worse prognosis for the victim.29 Men who experienced multiple episodes of sexual abuse in childhood are more likely than those who had a single episode to report suicidal ideation and to have sexual contact with a minor as adults.30
Previous studies have suggested that patterns of psychological disturbances are different for boys and girls.10,31- 33 Boys typically demonstrate more externalizing behavior than girls, including aggression, cruelty, delinquency, and hyperactivity. Girls tend to exhibit more internalizing behavior, such as depression, anxiety, and somatic concerns. However, studies that have examined the role of gender in psychological responses to childhood sexual abuse have been limited to primarily clinical samples with small numbers of patients. Few studies have looked specifically at adolescents,34,35 and still fewer have reported large numbers of males with a history of forced or pressured sexual experiences.9,10
This study examined whether gender-specific relationships between having been forced or pressured to have sexual intercourse and patterns of current risk behavior exist among sexually active middle and high school students in Vermont. We hypothesized the following: (1) that students who reported risk behaviors would be more likely to report having been forced or pressured to have sex; and (2) that gender differences would exist, with male students who reported externalizing behavior such as violence and female students who reported internalizing behavior such as bulimia and suicidal ideation more likely to report a history of having been forced or pressured to have sex. Sexually active adolescents engage in more risk behaviors than their nonsexually active counterparts.36 Analyses, therefore, need to take into account sexual activity when comparing sexually abused samples with nonabused samples to avoid confounding of associations of forced or pressured intercourse with risk behaviors.6 For this reason, we analyzed data specifically from sexually active adolescents.
The Centers for Disease Control and Prevention, Atlanta, Ga, developed the Youth Risk Behavior Survey (YRBS) to assess the prevalence of health risk behaviors among youth in the United States. Based on the national YRBS instrument, the 1995 Vermont YRBS was administered to 21297 eighth- through 12th-grade students attending 79 public and private schools in the state. All schools in the state were invited to take part in the survey; 53% (79/150) of the schools volunteered to participate. Each school that participated had a survey coordinator who arranged to obtain informed consent according to the individual school policy. Participation by students was voluntary and anonymous; 85% of the students in participating schools completed the survey, representing 60% of all eighth- through 12th-grade students in Vermont in 1995. The self-administered questionnaire consisted of 91 multiple choice questions and was available in English and Spanish. Demographic information collected included age, gender, and grade. In addition, information was acquired from the State of Vermont Agency of Human Services, Burlington, for each county on the average annual wage, the percentage of the county that is rural, and the percentage of children living in poverty. As Vermont middle and high school students are 97.5% white, information on race was not included in the survey to protect the confidentiality of students from minority racial and ethnic groups.
To select students who had been sexually active for data analysis, students had to answer consistently to 5 questions on sexual intercourse. Thirty-seven percent of the students (7884 students, 3931 girls and 3953 boys) consistently reported having had sexual intercourse on the 5 questions; data from these questions were included in the analyses of this article. The questions were as follows: "Have you ever had sexual intercourse?," "How old were you when you had sexual intercourse for the first time?," "Did you drink alcohol or use drugs before you had sexual intercourse the last time?," "The last time you had sexual intercourse, did you or your partner use a condom?," and "The last time you had sexual intercourse, what one method did you or your partner use to prevent pregnancy?" Response choices to each of the last 4 questions included "I have never had sexual intercourse." Of the total students surveyed, 51.3% (10919) reported never having sexual intercourse; 11.7% (2494) were inconsistent responders and were excluded from these analyses. The students in the nonsexually active group were younger, were in lower grades, and lived in more rural counties, with a lower average annual wage and a higher percentage of children living in poverty, than the students in the sexually active sample (P<.001).
Youth Risk Behavior Survey questions on ever having sexual intercourse, age at first sexual intercourse, and ever having been pregnant, as well as most questions on drug use, have been shown to have adequate reliability on test-retest analysis.37 More than 100 consistency checks were conducted on the Vermont YRBS data to exclude careless, invalid, or logically inconsistent responses.38 In addition, analyses were limited to students who responded consistently to questions on having sexual intercourse.
The dependent variable was addressed by the question, "Have you ever been forced or pressured to have sexual intercourse?" Responses included yes and no. Violent behavior was assessed by the questions, "During the past 12 months, how many times were you in a physical fight?" (0 or ≥1 time) and "During the past 30 days, on how many days did you carry a weapon such as a gun, knife, or club?" (0, 1, 2 or 3, 4 or 5, or ≥6 days). Suicidal ideation was assessed by the question, "During the past 12 months, did you ever seriously consider attempting suicide?" Recent drug use indicators included the following questions on tobacco use, "During the past 30 days, on how many days did you smoke cigarettes?" (0 or ≥1 day) and "During the past 30 days, on how many days did you use chewing tobacco or snuff, such as Redman, Levi Garrett, Beechnut, Skoal, Skoal Bandits, or Copenhagen?" (0, 1 or 2, 3-5, 6-9, 10-19, 20-29, or all 30 days). Recent alcohol use was assessed by the questions, "During the past 30 days, on how many days did you have at least one drink of alcohol?" and "During the past 30 days, on how many days did you have 5 or more drinks of alcohol in a row, that is, within a couple of hours?" (binge drinking). Response categories included 0 and 1 or more days. The number of times a student used marijuana (0 or ≥1 time) and the number of times a student used cocaine (0, 1 or 2, 3-9, 10-19, 20-39, or ≥40 times) were assessed by similar questions. Questions on age at first sexual intercourse, alcohol or drug use before last sexual intercourse, condom use at last sexual intercourse, number of male and female sexual partners in the past 3 months (0, 1, 2, 3, 4, 5, 6, or more), and number of times pregnant or gotten someone pregnant (0, 1, 2, or more) were also analyzed. Number of years sexually active was determined from age at the time of the survey and age at first sexual intercourse. Unhealthy weight control behavior was assessed by the questions, "During the past 30 days, did you vomit or take laxatives to lose weight or to keep from gaining weight?" (yes or no) and "During the past 30 days, did you take diet pills to lose weight or to keep from gaining weight?" (yes or no).
Pearson χ2 tests were used to compare differences in categorical results and a Kruskal-Wallis analysis of variance was used for ordinal variables. Multiple logistic regressions using the backward elimination method were calculated for the dichotomous dependent variable. For the independent variables, we report the unadjusted odds ratios (ORs) from the bivariate analyses and the adjusted ORs for those variables that remained significant during the multivariate analyses. For each independent variable measured on an ordinal or continuous scale, the OR represents the change in the risk of a history of having been forced or pressured to have sex for each increase or decrease in the unit of the scale. Results were considered significant at P≤.05. In contrast to the national YRBS, the Vermont YRBS does not use a complex survey design; all students in the selected schools were surveyed. Consequently, all analyses were performed using computer software (SPSS for Windows, version 6.0, SPSS Inc, Chicago, Ill).39 The numbers reported in the tables vary slightly because of missing data.
The demographic characteristics for the sexually active subsamples are given in Table 1. The sample was 50% male. Data on the counties in which the students attended school were also analyzed. The counties were, on average, 69% rural. The mean average annual wage was $21252. The mean percentage of children living in poverty was 16.1%. Data on male and female students were analyzed separately.
Reported risk behaviors among sexually active girls and boys are given in Table 2. For the sexually active girls, fighting was common and suicidal ideation was remarkably high. Alcohol use was the most prevalent drug use behavior. Tobacco use was also prevalent. Almost half of the girls reported using marijuana in the past month. Diet pill use and vomiting or laxative use were common.
The mean (±SD) age of onset of sexual intercourse was 14.3±1.5 years, and the mean (±SD) number of years sexually active was 1.8±1.4 years. Half of the girls did not use a condom at last sexual intercourse. Almost 30% used drugs or alcohol before last sexual intercourse.
More than 30% of sexually active girls (n=1192) reported a history of having been forced or pressured to have sexual intercourse. On bivariate analysis, almost all of the risk variables were significantly associated with having been forced or pressured to have sexual intercourse and these variables were entered into a logistic regression analysis (Table 3). Sexually active girls who reported more years of sexual activity, having been in 1 or more physical fights in the past 12 months, having seriously considered suicide, having not used a condom at last sexual intercourse, and having been pregnant more times were more likely than other girls to report a history of having been forced or pressured to have sex.
More than half of the sexually active boys had been in a physical fight in the past year (Table 2). Almost one third had seriously considered suicide in the past year. As expected, unhealthy weight control behaviors were less common among boys than girls. Drug use was prevalent and similar to the results found among girls. Boys reported the onset of sexual activity at an early age and multiple sexual partners. In addition, 5.1% of the boys reported at least 1 male sexual partner in the past 3 months. Compared with girls, boys more frequently reported using a condom at last sexual intercourse; however, one third used drugs or alcohol at last sexual intercourse and almost 10% had been involved in a pregnancy.
A history of having been forced or pressured to have sexual intercourse was reported by almost 10% (n=392) of sexually active boys. On bivariate analysis, all of the risk variables were significantly associated with a history of having been forced or pressured to have sexual intercourse and these variables were entered into a logistic regression analysis (Table 4). Similar to the girls, boys who reported having seriously considered suicide, more years of sexual activity, having not used a condom at last sexual intercourse, and being involved in more pregnancies were more likely to report a history of having been forced or pressured to have sex. In addition, boys who reported having more male partners in the past 3 months, having more female partners in the past 3 months, and having recently vomited or used laxatives were more likely to report a history of having been forced or pressured to have sex.
This study explored gender differences in patterns of risk behaviors associated with a positive response to a question about having been forced or pressured to have sexual intercourse by sexually active students who completed the Vermont 1995 YRBS. To our knowledge, it is the largest study of one state's population of middle and high school students. Boys and girls who reported seriously considering suicide, more years of sexual activity, engaging in sexual risk behaviors, and being involved in pregnancy were more likely to report having been forced or pressured to have sex. However, contrary to our hypothesis, sexually active girls who had been in physical fights were more likely to report a history of having been forced or pressured to have sex. Sexually active boys who were engaging in unhealthy weight control behaviors were more likely to report a history of having been forced or pressured to have sex.
There is limited literature on male victims of sexual assault and abuse, particularly in nonclinical samples. Previous research has suggested that male victims are more likely to exhibit externalizing behavior, such as aggression, while female victims demonstrate more internalizing behavior, such as depression and somatic concerns.10,31 However, at least 1 study of young adult men notes internalizing behavior among men who experienced long-term abuse as children.30 One fifth of victims reported depression, and one third reported a suicide gesture or attempt. Our results indicate that boys and girls who report suicidal ideation have an increased likelihood of a history of having been forced or pressured to have sex. Boys and girls who had been involved in pregnancy and were not using condoms were also significantly more likely to report having been forced or pressured to have sex. The sexually active boys in our sample who reported recently engaging in purging behaviors were 3.44 times more likely than other sexually active boys to report a history of having been forced or pressured to have sex. In contrast, while girls with bulimic behavior were not found to have an increased likelihood of a history of having been forced or pressured to have sex, girls who had been in at least 1 physical fight in the past year were 1.65 times more likely than other sexually active girls to report a history of having been forced or pressured to have sex.
Previous studies have found a strong association between forced or pressured sex and risk behaviors among adolescents.4- 7 However, these studies were performed in younger samples, in different regions of the United States, or in samples with a varied racial composition; these studies did not find major differences in patterns of risk behaviors between boys and girls. In addition, all but one of these studies did not distinguish between sexually active and nonsexually active students who reported a forced or pressured sexual experience.
As reported in previous studies,36 sexually active students in our study were engaging in notable sexual risk and drug use behaviors. Several studies and reviews suggest that drug and alcohol abuse is common in adults who experienced childhood sexual abuse,29,40 in psychiatrically hospitalized adolescents,19 and in sexually active eighth- and 10th-grade students.5,6 However, recent drug use was not strongly associated with having been forced or pressured to have sex in this nonclinical school-based sample, which agrees with at least 1 previous study of high school students.7 As drug use is associated with sexual activity,36 by restricting our analysis to only sexually active students the association between drug use and a history of having been forced or pressured to have sex may no longer be significant.
It is unlikely that there was overreporting of nonvoluntary or coercive sexual intercourse. However, because of the sensitive nature of the question, the reported incidence in this sample may underestimate the true incidence of having ever been forced or pressured to have sexual intercourse. Those students who had been forced to have sexual intercourse at a young age or under violent circumstances may consider questions on having had sexual intercourse to refer only to voluntary sexual experiences. Such misclassification would bias the results toward the null hypothesis. Other studies of female adolescents and young adults have shown a prevalence of a self-reported history of forced sexual intercourse of 12.9% to 17.0%.4- 6,8,9 In this study, 17.1% of female students reported having been forced or pressured to have sex. Among sexually active female students, the prevalence of having been forced or pressured to have sex was 30.3%. The question used in the YRBS did not distinguish among the range of nonvoluntary or coercive sexual experiences, which can include date rape, rape, and childhood sexual abuse. If data among college women are any indication,2,11,12 date rape alone may make up a substantial proportion of reported forced or pressured sexual experience among sexually active adolescent girls. The 9.9% prevalence of forced sex among sexually active boys in this study is consistent with previous research, which has indicated a prevalence of 3.5% to 15.6% among boys and young men.3- 5,8,30
This study had several limitations. Causality cannot be inferred from a cross-sectional study. Sampling was restricted to adolescents who were eighth- through 12th-grade students and who were present on the day of the survey. This study probably underestimates the true prevalence of the sexual risk and drug use behaviors among this age group as these behaviors are associated with poor school attendance and dropping out of school.41 Risk-taking behavior, such as agreeing to go into a car, house, or apartment with a male known for less than 24 hours, using alcohol or other drugs, or hitchhiking, has been associated with episodes of sexual assault among female adolescents.42 We were unable to control for such behavior in this study. Having ever been forced or pressured to have sexual intercourse was assessed by only a single question. There has not been adequate research done to assess the measurement issues involved in how adolescents view prior experiences when responding to a question on having been forced or pressured to have sexual intercourse in self-administered surveys and whether completion of intercourse at that time has to have occurred. Information was also not available on the gender of the offender, relationship to the offender, type of sexual act, age at onset or duration of the nonvoluntary sexual activity, or factors that have been shown to be related to subsequent psychological symptoms.9,29,40
Having ever been forced or pressured to have sex should be an essential part of the medical history for every young person. Youth who report nonvoluntary sexual experiences should receive risk counseling and be screened regularly for the development of sexual risk behaviors, drug use, and suicidal ideation. Adolescents engaging in risk behaviors should be carefully screened for suicidal ideation and a history of nonvoluntary or coercive sex. In particular, girls reporting violent behavior should be examined for a forced or pressured sex experience. Boys reporting unhealthy weight control behaviors should be screened carefully for a history of forced or pressured sex. Increased awareness and future study of the associations between forced or pressured sex and gender-specific risk behaviors will facilitate risk prevention, early detection, and appropriate referral for these at-risk youth.
Accepted for publication August 11, 1997.
This study was supported by the Maternal-Child Health Bureau, Health Resources and Services Administration, US Department of Health and Human Resources (Project MCJ-MA259195), Rockville, Md.
Presented in part at the Society for Adolescent Medicine Annual Meeting, San Francisco, Calif, March 7, 1997.
We thank the Vermont Department of Public Health, Burlington, for providing data and informational support; Steven L. Gortmaker, PhD, for his initial guidance and helpful comments; and Ralph J. DiClemente, PhD, for his review of the manuscript.
Editor's Note: The gender reversal behaviors associated with having been forced or pressured into sexual intercourse are fascinating. The high incidence of such pressure in the general population of adolescents is depressing.—Catherine D. DeAngelis, MD
Corresponding author: Lydia A. Shrier, MD, MPH, Division of Adolescent/Young Adult Medicine, Children's Hospital, 300 Longwood Ave, Boston, MA 02115 (e-mail: email@example.com).
Shrier LA, Pierce JD, Emans SJ, DuRant RH. Gender Differences in Risk Behaviors Associated With Forced or Pressured Sex. Arch Pediatr Adolesc Med. 1998;152(1):57-63. doi:10.1001/archpedi.152.1.57