Sexual activity among younger teens is rare, and those having sex at 10 or younger are usually victims of coercion, according to the Guttmacher Institute.

Among those born in the years from 1984 to 1993, only 1% of girls reported having sexual intercourse when they were 11 years old or younger, according to the research published online in Pediatrics. Only 2% of 12-year-olds and 5% of 13-year-olds reported having sexual intercourse.

If children younger than 10 reported having sexual intercourse, it typically was coerced or nonconsensual, according to Lawrence B. Finer, PhD, and Jesse M. Philbin, BA, of the Guttmacher Institute, a reproductive rights organization based in New York City.

“Concerns about substantial levels of sexual activity among young adolescents are unfounded, and the pregnancy rate (indeed, the absolute number of pregnancies) among these girls is vanishingly small,” the authors wrote.

Sexual activity and pregnancy are rare among 10-, 11-, and 12-year-olds, and sex is more likely to be nonconsensual, the authors said. “This arguably represents a different public health issue than sex among older teens, who have a greater need for contraception,” they wrote.

Younger Teens Rarely Studied

Although rates of teen pregnancy have declined in recent decades, “teen sex remains a prominent bogeyman, as there is a broad public perception that a substantial proportion of young adolescents are sexually active,” the authors noted in their introduction. Previous studies have looked at reproductive activity among teens 14 and younger, but those studies date from the late 1990s and “none of them presented information on the youngest adolescents (those 12 and younger),” they wrote.

To clarify the issue further, the authors looked at data from the National Survey of Family Growth. The survey is “a nationally representative survey of women and men aged 15–44, conducted by the National Center for Health Statistics, that is arguably the best source of information on sexual activity, partnership patterns, contraceptive use, and childbearing in the United States,” they explained.

The investigators initially evaluated data from 3,242 females and 3,104 males born during the years 1984 to 1993, who responded to the survey in the years 2006 to 2010. But to further examine long-term trends related to first sexual intercourse, they also separated certain groups of female respondents from that survey and earlier surveys into birth cohorts from 1939 to 1991 and assessed the ages by which 10%, 25%, 50%, 75%, and 90% of each cohort had had sex.

Using that data, the authors determined that the median age for first-time sex in the U.S. over the past 50 years has not fallen beneath age 17.

Most Older Teens Not Sexually Active

Looking at the data from the 2006-2010 respondents, the authors found that at age 15, the incidence of first-time sexual intercourse increased, but sexually active teens remained in the minority: 19% of 15-year-old girls and 32% of 16-year-old girls reported having sexual intercourse. In general, younger generations put off having sex later in life than their elders born in the 1970s, they said.

By age 20, some 26% of all women had not had sex, they wrote.

Figures for young males were also low, although slightly higher than for females:

  About 2% of boys had had sex by age 12
  About 5% and 10% of boys by age 13 and 14, respectively, had had sex
  In older teens, 22% of 15-year-old boys, and 35% of 16-year-old males had had sex, just a few percent higher than girls
  By age 20, the proportion of men who had not had sex was the same as it was for women

For 10-year-old girls, 62% reported sexual initiation was nonconsensual or coerced; for 11-year-olds, it was 50%; and for 12-year-olds, it was 23%. The numbers dropped considerably at age 13 and 14, when 7% reported that first sex was not consensual. By age 17 or older, fewer than 5% reported sexual initiation was forced.

Rates of sexual coercion were limited to females, as the male data did not include the necessary variable, the authors said.