Updated

Sexual activity is on the rise among U.S. teens while their use of contraceptives is sliding in the other direction, according to a study released on Wednesday by the Centers for Disease Control and Prevention.

Click here to view the study.

Approximately 48 percent of 14,041 high school students said they have had sex, representing a 2 percent hike since 2005; however, teens still are having less sex today than their counterparts did in the 1990s.

The 2007 Youth Risk Behavior Surveillance System study showed a 2 percent drop-off in the percentage of teens who said they used condoms while having sex.

The CDC questioned the students on a range of risky behaviors including sexual activity and drug and alcohol use. Ninth- through 12th-graders from 39 states participated in the study in spring 2007.

In 1991, 54 percent of the high school students said they had had sexual intercourse, compared with 48 percent in 2007. In 1991, 19 percent said they had at least four sexual partners, compared with 15 percent last year, the survey showed, Reuters reported.

For the students overall, just under half have had sex, 75 percent have tried alcohol and 20 percent said they smoke.

The study is given to high school students every two years. The new report noted that black and white students are reporting less sexual activity than in years past, but there was no decline among Hispanics.

Whites, however, reported the highest rates of smoking and heavy drinking, while blacks reported the highest rates of obesity and violence.

Hispanic students were more likely than either blacks or whites to use cocaine, heroin or ecstasy, attempt suicide or ride with a driver who had been drinking alcohol.

The survey did not collect information on the parents' income or education levels. Some experts say those factors can be a strong indicator of a youth's health behavior and academic achievement.

Adolescents cannot always be counted on to tell the truth about their sexual exploits, drug use or other risky behaviors, but CDC officials said they take many steps to secure accurate responses: Participation is confidential, kids are spaced apart when answering the questions and teachers do not hover.

The Associated Press contributed to this report.

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