Around two in five never-married female and male teenagers have had sex, a newly released study shows.
The proportion of 15- to 19-year-olds having sexual intercourse has steadily decreased over the past couple of decades, according to the Centers for Disease Control and Prevention report.
In 2006-2008, 42 percent of female teens and 43 percent of male teens said they had sex, down from 51 percent in 1988 among females and 55 percent in 1995 among males.
Among teens that had not yet had sex, the most common reason for not yet having done so was that it was "against religion or morals," the report noted.
Other common reasons listed were "don't want to get pregnant" and "haven't found the right person yet."
Among the sexually experienced, the majority had "first sex" with someone with whom they were "going steady." Meanwhile, 14 percent of female teens and a quarter of male teens had first sex with someone they had just met or with whom they were "just friends."
Among females aged 18-24 whose first sex was before age 20, 10 percent "really didn't want it to happen at the time," 47 percent had mixed feelings, and 43 percent "really wanted it to happen at the time," according to the report.
Teens' attitudes about sexual activity and childbearing are becoming less and less traditional.
Males are more likely, compared to 2002, to say it is OK for an unmarried female to have a child and to agree that any sexual act between two consenting adults is all right.
The majority of females also agree that it is OK for an unmarried female to have a child.
The CDC report is based on data collected through in-person interviews with 2,767 teenagers in the United States, conducted between July 2006 and December 2008.