Initial sexual intercourse
The average age of first sexual intercourse in the United States is 17.0 for males and 17.3 for females. Most American teenagers are virgins, and the percentage of teens who are virgins has been increasing. 43% of unmarried teenage girls and 42% of unmarried teenage boys have ever had sexual intercourse, according to a 2011 study. In 2002, the last year such a report was published, 46% of girls and 46% percent of boys had had sex by 19. Among younger teens, the majority claim to be virgins, and this percentage has risen over time. Most non-virgins (78% of girls and 85% of boys) used contraception the first time they had sex.
Sixteen percent of adults first had sex before age 15, while 15 percent abstained from sex until at least age 21. The proportion of adults who first had sex before age 15 was highest for non-Hispanic blacks (28 percent) compared to 14 percent for both Mexican-Americans and non-Hispanic whites. Six percent of blacks abstained from sex until age 21 or older, fewer than Mexican-Americans (17 percent) or non-Hispanic whites (15 percent).
Girls will most likely lose their virginity to a boy who is 1 to 3 years older than they are. According to one study, almost 14 percent of teens lose their virginity in June, the most common month. The teen's home, their partner's home or a friend's house is the most common place for virginity to be lost, with 68% of teens losing their virginity in one of those three places. The same study found that "the likelihood of a first sexual experience happening will increase with the number of hours a day teens spend unsupervised." Other research has found that teens from non-intact homes are more than 50% more likely to have had sexual intercourse.
Factors that correlate with teen sexual activity include:
"Individual—having a history of sexual abuse, depression, heavy alcohol or drug use.
Family—living in a single parent or stepparent household, living in a poor household, having parents with permissive values about sexual activity, having little supervision from parents, having siblings who are sexually active, feeling unloved, unwanted, or not respected by parents.
Community—having friends who are sexually active, having few positive experiences at school, living in a neighborhood with poor neighborhood monitoring."
Unwanted initial sexual intercourse
Surveys indicate that the majority of American teens who have had sex wish they had waited. Among sexually active girls, two-thirds say they didn't want to lose their virginity when they did or that they had mixed feelings about it.
1% chose to have sex when they were 13 or younger, 5% at 14 or 15 years old, and 10% at 16 or 17 years old. Another 42% reported that losing their virginity before age 18 was not completely wanted, while the remaining portion of the sample waited until age 18 or older to have sex (wanted, 22%; unwanted, 21%).
A first sexual experience that was unwanted or not completely wanted was strongly associated with future divorce. "If the sex was not completely wanted or occurred in a traumatic context, it's easy to imagine how that could have a negative impact on how women might feel about relationships, or on relationship skills," Anthony Paik, associate professor of sociology at the University of Iowa, said. "The experience could point people on a path toward less stable relationships."
Current sexual activity
The percentage of teenagers who report they are currently sexually active has also been dropping since 1991. In 1997, only 37% of females and 33% of males who reported ever having had sexual intercourse said that they had sex in the past 3 months. 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 is "quite positive in terms of their health and their well-being," said Edward Sondik, director of the National Center for Health Statistics.
Oral sex
The National Center for Health Statistics has reported that half of all 15- to 19-year-olds have had oral sex, with the percentage rising to 70% by the time they turn 19, and equal numbers of boys and girls participating. A 2007 Guttmacher Institute study found that slightly more than half (55%) of 15– to 19-year-olds have had heterosexual oral sex, 50% have had vaginal sex and 11% have had anal sex, and that the prevalence of both vaginal and oral sex among adolescents has remained steady over the past decade.
This data indicates that many teens, particularly those from middle- and upper-income white families, don't consider oral sex to be as significant or meaningful as older generations do. Almost half of boys (47%) and fewer girls (38%) believe that oral sex is "not as big of a deal as intercourse", and 55% of teens believe that it is "very important" to be in love before engaging in oral sex. Despite this, "there is discrepancy when it comes to willingness to perform oral sex with 22% of sexually active girls saying their partner never performs oral sex on them, while only 5% of boys say their partner never does."
Researchers at the University of California, San Francisco believe that some teens, and particularly girls, engage in oral sex as a way to avoid vaginal intercourse. A study released in 2008 by the Guttmacher Institute supported this substitution theory. "There is a widespread belief that teens engage in nonvaginal forms of sex, especially oral sex, as a way to be sexually active while still claiming that technically, they are virgins," says study author Laura Lindberg. However, the study drew the contradictory conclusion that "research shows that this supposed substitution of oral sex for vaginal sex is largely a myth."
New York Times columnist David Brooks has written, "Reports of an epidemic of teenage oral sex are .. greatly exaggerated" Researchers believe that oral sex may have become more popular than intercourse for adolescents because teens believe it carries fewer physical and emotional risks, a claim one study supports.
Contraceptive use
Among sexually active 15- to 19-year-olds, 83% of females and 91% of males reported using at least one method of birth control during last intercourse. Thus, sexually active adolescent women wishing to avoid pregnancy are less likely than those of other ages to use contraceptives (18% of 15- to 19-year-olds used no contraceptives, versus 10.7% average for women ages 15 to 44), according to an analysis of periodic survey data from the National Center for Health Statistics.
Among adolescents, the most common methods of contraception are birth control pills (used by 43.5% of 15- to 19-year-old women at risk for unintended pregnancy) and condoms (used by 22% of adolescent women). In 2007, 61.5% of high school students reported using a condom the last time they had sexual intercourse, up from 46% in 1991. Adolescent women are more likely to use Depo Provera (11% of teens versus 4.8% for women ages 15 to 44) but less likely to use IUDs (0.2% versus 1.9% overall), which require little user action and are thus among the most effective in typical use.
While 90% of teens surveyed in a poll commissioned by NBC News and People magazine knew they could get an STI from having sexual intercourse, only 67% said that they use protection every time they have sex. Boys who have received sex education are three times more likely to use contraception than their peers who have not, but for girls there is no difference. Before the 1980s, 57% of 15- and 16-year-old girls did not use contraception the first time they had intercourse. By 2007, that number fell to 25%.
Girls who stop using contraception after the first time they have intercourse have been found less likely than those who continue to use it to be able and willing to plan for sexual intercourse, less apt to believe that pregnancy was likely to occur and less apt to want to remain non-pregnant. They were also more likely to be older and to have been sexually active for at least 6 months. Girls who stopped using contraception were also less likely to have career goals and had more positive expectations themselves about the effects of childbearing on their lives.
Abstinence
For the last 20 years abstinence rates among American adolescents have risen. The percentage of high school students in the U.S. who reported that they have ever had sexual intercourse dropped from 54.1% in 1991 to 47.8% in 2007 and to 43% in 2011. A cross-sectional survey 73,464 of adolescents in Minnesota conducted 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, along with a fear of sexually transmitted infections. Other reasons included a lack of desire, being afraid of getting caught, and the belief that sex was not appropriate for someone of their age.
Adolescents who have received sex education in school or church settings are less likely to be sexually active. For girls, they were 59% less likely and boys were 71% less likely. Epidemiologists at the Center for Disease Control emphasize that for sex education to be effective, it should take place before teens become sexually active.