More girls in the U.S. are remaining virgins until their late teens and into their 20s, with the biggest rates of decline in sexual activity seen among African-Americans and Hispanics, the CDC says.

More than half of girls between the ages of 15 and 19 -- 57% -- reported that they had never had vaginal intercourse in the latest CDC survey covering 2006-2010, up from 49% in 1995.

More Teens Using Birth Control

For the first time since the CDC began gathering data on teen sex practices, the percentage of teen girls who reported having never had sex was the roughly the same for African-Americans, whites, and Hispanics.

Racial disparities persist, however, in the number of teen girls using the most effective forms of birth control, including hormonal pills, patches, rings, implants, injections, and IUDs with or without condoms.

Roughly 60% of sexually active teens reported using these forms of birth control between 2006 and 2010, up from 47% in 1995.

In the latest survey, 2 out of 3 (66%) sexually active white teens said they used highly effective birth control, compared to 46% of African-American teens and 54% of Hispanic teens.

The delay of sexual activity and the increased use of birth control are largely responsible for a sharp decline in teen births in the U.S., says CDC epidemiologist Crystal Pirtle Tyler, PhD.

"Many teens still believe most of their peers are having sex, even though the data show that the majority aren't," she tells WebMD. "That is why it is so important to get the message out that the majority of teens are not having sex."

Teen Pregnancy at 30-Year Low

Teen pregnancy rates have dropped more than 40% since their peak in 1990, and they remain at a 30-year low.

In 2010, the birth rate among 15- to 19-year-olds was 34 births per 1,000 teen females, a 44% decline in just two decades.

Tyler says it is clear from the declining birth rate and the latest survey that comprehensive sexual education and abstinence-based programs aimed at delaying teen sexual activity have had an impact.

She adds that organizations like the CDC, the American Academy of Pediatrics, and other groups are increasingly using social media to reach teens.

The new report was based on a nationally representative survey of 2,300 teen girls ages 15 to 19. Survey findings are published in the CDC's Morbidity and Mortality Weekly Report.

Among the other key findings:

• Only about half of sexually active teen girls who said their partners used condoms reported consistent condom use.
• Between the first and most recent surveys, the percentage of teen girls who reported never having had sex increased by 34% among African-Americans, 29% among Hispanics, and 15% among whites.
• Even with the decline in teen pregnancies, the birth rate among teens in the U.S. is still among the highest of any industrialized nation.

SOURCES:Morbidity and Mortality Weekly Report, May 4, 2012.Crystal Pirtle Tyler, PhD, epidemiologist, CDC.

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