(AP) -- Almost all U.S. teens have had formal sex education, but only about two-thirds have been taught about birth control methods, according to a new government report released Wednesday.
Many teens apparently are not absorbing those lessons - other recent data shows that after years of steady decline, the teen birth rate rose from 2005 to 2007. It dipped again in 2008, to about 10 percent of all births.
The report from the Centers for Disease Control and Prevention is based on face-to-face interviews with nearly 2,800 teenagers in their homes from 2006 through 2008. Female interviewers from the University of Michigan asked the questions for the CDC.
About 97 percent of teens said they received formal sex education by the time they were 18. Formal sex education was defined in the report as instruction at a school, church, community center or other setting teaching them how to say no to sex or about birth control and sexually transmitted diseases.
Lessons about saying no and STDs were more common than instruction on how to use a condom or other birth control, the study found.
Overall, about two-thirds of teens got birth control instruction by the end of high school - about 62 percent of boys and 70 percent of girls.
In contrast, about 92 percent of boys and girls reported being taught about sexually transmitted diseases, and almost that many learned about preventing infection with the AIDS virus. And about 87 percent of girls and 81 percent of boys were taught how to say no to sex.
The study also found that younger teen girls were more likely than boys to have talked to their parents about sex and birth control, and how to say no to sex.
The report does not address trends in sex education. But many of the findings were similar to some CDC research conducted in 2002.
Other research suggests that comprehensive sex education declined from 1995 to 2002, and this report seems to indicate that it hasn't changed since then, said John Santelli, a Columbia University professor of population and family health.
Government policies stressing abstinence-only sex education were a large reason for that initial decline. Programs noted the threat of sexually transmitted diseases but not how to use birth control. Those policies were still in place when the CDC study was done, Santelli said.
But in the last two years, most of federal funding for sex education has been redirected to programs that discuss birth control as well as the importance of delaying sex, said Bill Albert, chief program officer for the Washington, D.C.-based National Campaign to Prevent Teen and Unplanned Pregnancy.
Another CDC study, released earlier this year, found that teenage use of birth control and teen attitudes toward pregnancy have remained about the same since 2002.
Previous CDC research found that that about 85 percent of high schools and 72 percent of middle schools teach human sexuality and sex education.
Explore further: Popular media influences choice of childbirth
More information: CDC report: http://www.cdc.gov/nchs