MONDAY, March 24 (HealthDay News) -- Comprehensive sex education may help reduce teen pregnancies without increasing levels of sexual intercourse or sexually transmitted diseases.

So find U.S. researchers who reviewed data from a 2002 national survey of more than 1,700 heterosexual teens, ages 15 to 19.

There is ongoing debate about whether abstinence-only education or comprehensive sex education (including instruction in birth control) is best for students.

Study lead author Pamela Kohler, a program manager at the University of Washington in Seattle, and colleagues found that about 25 percent of teens received abstinence-only education and about two-thirds received comprehensive sex education. About 9 percent -- particularly teens from poor families and those in rural areas -- received no sex education at all.

The researchers found that teens who received comprehensive sex education were 60 percent less likely to get pregnant or to get someone pregnant than those who received no sex education.

Other results -- not statistically significant, however -- suggested that comprehensive sex education, but not abstinence-based sex education, slightly reduced the likelihood of teens having vaginal intercourse. Neither approach seemed to reduce the likelihood of reported cases of sexually transmitted diseases.

The findings, published in the April issue of the Journal of Adolescent Health, support comprehensive sex education, Kohler concluded.

"There was no evidence to suggest that abstinence-only education decreased the likelihood of ever having sex or getting pregnant," she said in a prepared statement.

This study offers "further compelling evidence" about the value of comprehensive sex education and the "ineffectiveness" of the abstinence-only approach, said Don Operario, a sex education expert and professor at Oxford University in England.