The sexuality of US adolescents includes their feelings, behaviors and development, and the place adolescent sexuality has in American society, including the response of the government, educators, parents, and other interested groups.

Teenage pregnancy is four times as prevalent in the US as in the European Union, but has been steadily declining since 1991, reaching a record low in 2012, according to the US Centers for Disease Control and Prevention (CDC), and continuing to decline through 2017. The CDC said in 2007, 35% of US high school students were currently sexually active and 47.8% of US high school students reported having had sexual intercourse. In 2017, the percentage sexually active was down to 28.7%, and the percentage who had ever had intercourse was 39.5%. According to a 1994 study, every year an estimated one in four sexually active teens contracts a sexually transmitted infection (STI).

In 1999, a Kaiser Family Foundation study found that 95% of public secondary schools offered sex education programs. More than half of the schools in the study followed a comprehensive approach that included information about both abstinence and contraception, while approximately one third of schools provided students with abstinence-only sex education. In 2002, most Americans favored the comprehensive approach. A 2000 study found that almost all schools included information about HIV, the virus that causes AIDS, in their curricula. There have been efforts among social conservatives in the US government to limit sex education in public schools to abstinence-only sex education curricula. The effectiveness of abstinence-only programs has been an issue of controversy.

Sexual practices

Self-report surveys suggest that half of those 15 to 19 have had oral sex. That percentage rises to 70% by the time they turn 19, and equal numbers of boys and girls participate. Research indicating that oral sex is less risky to teens' emotional and physical well-being than vaginal sex has been advanced; researchers at the University of California, San Francisco, do not believe that conclusion is warranted. They found that oral sex, as well as vaginal sex, was associated with negative consequences. Of adolescents engaging in oral sex only, girls were twice as likely as boys to report feeling bad about themselves, and nearly three times as likely to feel used. Despite their behaviors, 90% of adolescents "agree that most young people have sex before they are really ready."

The average age of first sexual intercourse in the United States is around 16.8 for males and around 17.2 for females, and that has been rising in recent years. For teens who have had sex, 70% of girls and 56% of boys said that their first sexual experience was with a steady partner, and 16% of girls and 28% of boys report losing their virginity to someone they had just met or who was just a friend.

Teens are using birth control (contraceptives) more today when they lose their virginity than they did in the past, and partly because of the AIDS epidemic. Of sexually experienced adolescents, 78% of girls and 85% of males used at least one contraceptive when they lost their virginity. In successive surveys of young adults conducted over a 30-year period, a majority of respondents reported that they felt they had sex for the first time at "the right age." However, women were more than twice as likely as men (45.8% vs. 21.6%) to express that they wished they had waited longer.

Before age 15, "a majority of first intercourse experiences among females are reported to be non-voluntary." A detailed qualitative study of girls' loss of virginity found that their experiences "were almost all quite negative (and, in some cases, horrific)."

Adolescents who are better students generally initiate sexual activity later than those who are poor students. In addition, among those seventh- and eighth-graders, those with personal and perceived peer norms that encourage adolescents to refrain from sex are less likely to engage in it.

The percentage of teenagers who report that they are currently sexually active has been dropping since 1991. By 2005, the overall percentage of teenagers reporting that they were currently sexually active was down to 33.9%. A lower number of sexually active teens are "quite positive in terms of their health and their well-being."

The condom is the most popular form of contraception used by teenagers. Among sexually-active 15-to-19-year-olds, from 2002 to 2010 more than 80% of females and more than 90% of males reported using at least one method of birth control during their last intercourse. In 1995, only 71% of girls and 82% of boys reported using contraception the last time that they had sex. In 2006 to 2010, one in five sexually-active female teens (20%) and one third of sexually active male teens (34%) reported having used both the condom and a hormonal method the last time that they had sex. Less than 20% of girls at risk for unintended pregnancy were not using any contraceptive method the last time they had sex. Calendar abstinence, or the rhythm method, was used by 17% of female teens in 2006 to 2008.

Sexual abstinence

Sexual abstinence is the practice of refraining from some or all aspects of sexual activity for medical, psychological, legal, social, financial, philosophical, moral, or religious reasons. For the last twenty years, abstinence rates among American adolescents have risen. The percentage of high school students in the US who reported that they have ever had sexual intercourse dropped from 54.1% in 1991 to 47.8% in 2007, 43% in 2011 and 39.5% in 2017. A cross-sectional survey in 1998 found that fear of pregnancy was the most commonly cited reason for choosing abstinence, especially among girls, as well as boys who had caused a pregnancy in the past. Other reasons included a fear of sexually transmitted infections, a lack of desire, being afraid of getting caught, and the belief that sex was not appropriate for someone of their age.

Epidemiologists at the Centers for Disease Control emphasize that for sex education to be effective, it should take place before teens become sexually active.

+Most common reasons virgins cite for remaining abstinent Reason Percent of 9th grade males Percent of 12th grade males Percent of 9th grade females Percent of 12th grade females Fear of pregnancy 15% 20% 82% 77% Fear of STDs 57% 46% 75% 61% Decision to wait until marriage 43% 47% 56% 58% Belief that sex was not right for a person their age 50% 33% 70% 51% Parents would object 56% 43% 64% 50% Both adolescents who have never had sex and those who have chosen to become abstinent after engaging in sexual behaviors cite the negative consequences of sex as reasons for choosing not to have sex. Girls of all ages and experience levels were more likely than boys to cite the fear of pregnancy and sexually transmitted diseases, while virgin boys were more likely than girls to say that they believed most students did not have sex.

Boys who caused a pregnancy in the past were more than twice as likely to become abstinent after that episode than other boys. However, for girls, a past pregnancy had little correlation with secondary abstinence. Fear of pregnancy, wanting to wait until marriage, and not wanting to have sex were cited more often by virgins in the 12th grade than in the 9th grade. Of the sexually experienced who are now practicing abstinence, girls were more likely than boys to say a lack of desire, fear of STDs, being afraid of getting caught, the belief that sex was not appropriate for someone their age, and their parents having taught them the advantages of waiting as reasons for making their decision.

Definitions of virginity Among young people engaging in some form of sexual activity, definitions of virginity differ. Virginity is usually defined as the state of a person who has never engaged in sexual intercourse, but there are some gray areas. For example, teenagers that engage in oral sex but not penile-vaginal sex may still identify themselves as virgins, which is sometimes termed technical virginity. Of those polled, 70% of adolescents 11–16 believed oral sex did not disqualify someone from virginity, and 30% believed they were still abstinent.

Of adolescents 11–16, 83% believe a person is still a virgin after engaging in genital touching, and 70% said they believed one retained their virginity after having oral sex. Additionally, 16% considered themselves virgins after anal sex. However, 44% believed that one was abstinent after genital touching, and 33% believed one could have oral sex and still remain abstinent. Of anal and vaginal sex, 14% believed one could engage in the former, and 12% said one could participate in the latter and still remain abstinent.

Among those 15–19 years old, those who remain a "technical virgin" are motivated more by the fear of pregnancy or STIs than by religion and morality.

Physical effects The American Academy of Pediatrics has identified the sexual behaviors of American adolescents as a major public health problem. It is concerned about the prevalence of sexually transmitted diseases in sexually-active teenagers and about the very high rate of teenage pregnancy in the United States compared to other developed countries.

Research into adolescents' sexual behavior in situations outside traditional dating situations, commonly referred to as "hooking up", shows that a large number of adolescents underestimate the risk involved in such situations.

Pregnancy

Teen pregnancies, defined as pregnancies in females under the age of 20, regardless of marital status, in the United States decreased 28% between 1990 and 2000 from 117 pregnancies per every 1,000 teens to 83. The 2008 rate was a record low and represented a 42% decline from the peak rate, which had occurred in 1990. From 2009 to 2010, the teen pregnancy rate dropped another 9%, the biggest one-year drop since the 1940s.

Each year, almost 750,000 girls 15–19 become pregnant. Two thirds of all teen pregnancies occur among the oldest teens (18–19). Of them, 82% are unplanned, which accounted for about 20% of all unintended pregnancies annually. Of pregnancies among girls aged 15–19 girls in 2008, 59% ended in birth, 26% in abortion, and the rest in miscarriage. Overall, 68 pregnancies occurred per 1,000 girls aged 15–19 in 2008. Nearly 7% of 15–19-year-old girls become pregnant each year. Pregnancies are much less common among girls younger than 15. In 2008, 6.6 pregnancies occurred per 1,000 teens aged 14 or younger. In other words, fewer than 1% of teens younger than 15 become pregnant each year. Stillborn and newborn deaths are 50% higher for teen moms than women aged 20–29 and are more likely to have a low birth weight.

Teenage birth rates, as opposed to pregnancies, peaked in 1991, when there were 61.8 births per 1,000 teens, and the rate dropped in 17 of the 19 years that followed. One in four American women who had sex during their teenage years will have a baby before they are married, compared to only one in ten of those who wait until they are older. Even more will experience a pregnancy. Of women who have sex in their teens, nearly 30% will conceive a child before they are married. Conversely, only 15% of women who do not have sex in their teens will become pregnant before they are married. Of all women, 16% will be teen mothers.