It's not clear why some of the sexually active teens don't use contraceptives since the survey didn't ask that question, Martinez said, although future research will ask about that.
The surveys did ask the teens who didn't have sex why they avoided it. The most common reason was that it was against their religion or morals; 41 percent of the females in that group said that was their most important reason, compared with 31 percent of males.
There wasn't much difference compared to 2002 in the percentage of teens who said they'd be at least somewhat pleased if a sexual encounter resulted in a pregnancy: 13 percent of females and 19 percent of males said they'd be a "little pleased" or "very pleased."
The findings suggest that the dip in sexual activity that began in the 1990s hasn't reversed itself, said Jennifer Manlove, a senior research scientist with Child Trends, a non-profit research organization that focuses on children and families. On the other hand, she said, "we're no longer seeing the big declines in sexual activity that we saw in the 1990s."
Researchers speculate that the big dip in sexual activity that occurred in that decade may have had something to do with the AIDS epidemic or an increased focus on abstinence in sex education, she said.
She said that while the new numbers about contraceptive use are promising, "there's still room to improve," especially when it comes to consistent use of birth control. Considering the role of the Pill and other medical devices, she said, "doctors need to focus on finding the right method that works for females, and keep them on the more effective methods [once] they are sexually active."
For details about teen sexual health, try the U.S. National Library of Medicine.
SOURCES: Gladys Martinez, statistician, U.S. National Cent
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