Sexual Risk Behaviors Can Lead to HIV, STDs, & Teen Pregnancy

  • Half of all new STDs reported each year are among young people 15 to 24.3
  • Nearly 46% of sexually active high school students did not use a condom the last time they had sex.1

Many Young People Engage in Sexual Risk Behaviors

diverse group of teens in school hallway

Many young people engage in sexual risk behaviors and experiences that can result in unintended health outcomes.

CDC data show that lesbian, gay, and bisexual high school students are at substantial risk for serious health outcomes pdf icon[PDF – 31 MB] related to sexual behaviors, violence, substance use, and poor mental health as compared to their peers.

Among U.S. high school students surveyed in 20191

  • 38% had ever had sexual intercourse.
  • 9% had four or more sexual partners.
  • 7% had been physically forced to have sexual intercourse when they did not want to.
  • 27% had had sexual intercourse during the previous 3 months, and, of these
    • 46% did not use a condom the last time they had sex.
    • 12% did not use any method to prevent pregnancy.
    • 21% had drunk alcohol or used drugs before last sexual intercourse.
  • Less than 10% of all students have ever been tested for HIV.
  • Less than 10% of all students have been tested for sexually transmitted diseases during the past year.

Source: National Youth Risk Behavior Survey, 2019

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CDC recommends everyone aged 13-64 get tested for HIV at least once as part of routine medical care.5,6

HIV, STDs, and Teen Pregnancy are Health Consequences

Sexual risk behaviors place youth at risk for HIV infection, other STDs, and unintended pregnancy:


21% of all new HIV diagnoses were among young people (aged 13-24) in 2018; 88% were young men and 12% were young women.2



Half of the 20 million new STDs reported each year were among young people (aged 15 to 24)3

Teen Pregnancy

Nearly 180,000 babies were born to teen girls (aged 15–19 years) in 2018.4


Abstinence from vaginal, anal, and oral intercourse is the only 100% effective way to prevent HIV, other STDs, and pregnancy. The correct and consistent use of male latex condoms can reduce the risk of STD transmission, including HIV infection. However, no protective method is 100% effective, and condom use cannot guarantee absolute protection against any STD or pregnancy.

Schools and Youth Serving Organizations Can Help

School health programs can help young people adopt lifelong attitudes and behaviors that support their health and well-being—including behaviors that can reduce their risk for HIV and other STDs.

HIV, STD, and teen pregnancy prevention programs in schools should

  • Provide health information that is basic, accurate, and directly contributes to health-promoting decisions and behaviors.
  • Address the needs of youth who are not having sex as well as youth who are currently sexually active.
  • Ensure that all youth are provided with effective education and skills to protect themselves and others from HIV infection, other STDs, and pregnancy.
  • Be developed with the active involvement of students and parents.
  • Be locally determined and consistent with community values and relevant policies.
National Strategic Plans
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  • The HIV National Strategic Planexternal icon calls for all Americans to be educated about HIV. This includes knowing how HIV is transmitted and prevented, and knowing which behaviors place individuals at greatest risk for infection. HIV awareness and educationpdf icon should be universally integrated into all educational environments.
  • The Sexually Transmitted Infections National Strategic Planpdf iconexternal icon aims to reverse the recent dramatic rise in STIs in the United States. Using health education to prevent STIs, schools, other professionals, and families can help adolescents make informed, positive, and safe choices about healthy relationships, responsible sexual activity, and their reproductive health.

CDC Programs & Initiatives

The prevalence of some health behaviors remains high and puts youth at higher risk for negative health outcomes and poor academic performance. CDC’s Division of Adolescent and School Health addresses HIV, other STDs, and unintended pregnancy prevention through

  1. CDC. Youth Risk Behavior Surveillance—United States, 2019. MMWR Suppl 2020;69(1):1-83.
  2. CDC. Diagnoses of HIV infection in the United States and dependent areas, 2018 (Updated). HIV Surveillance Report 2020;31.
  3. CDC. Sexually Transmitted Disease Surveillance 2018. Atlanta: U.S. Department of Health and Human Services; 2019.
  4. Martin JA, Hamilton BE, Osterman MJK, Driscoll AK. Births: Final data for 2018. National Vital Statistics Reports; vol 68, no 13.pdf icon Hyattsville, MD: National Center for Health Statistics. 2019.
  5. Final Update Summary: Human Immunodeficiency Virus (HIV) Infection: Screening.external icon U.S. Preventive Services Task Force. November 2018.
  6. CDC.  Revised recommendations for HIV testing of adults, adolescents, and pregnant women in health-care settings. MMWR 2006;55:1-17.