NASHVILLE (AP) — Spurred by a classroom demonstration involving a sex toy, Tennessee recently enacted a pro-abstinence sex education law that is among the strictest in the nation.

The most debated section of the bill bars educators from promoting "gateway sexual activity." But supporters seemed too squeamish during floor debate to specify what that meant, so critics soon labeled it the "no holding-hands bill."

One thing missing from the debate in the Legislature was a discussion of whether the law signed by Republican Gov. Bill Haslam last month really would help reduce Tennessee's high teenage pregnancy rate. Experts say it won't and warn that it leaves teenagers inadequately educated about sexuality and prevention of pregnancy and disease.

Tennessee's pregnancy rate among girls 15 to 17 has dropped steadily since the first abstinence-focused sex education curriculum was put in place in the 1990s, according to figures from the state Commission on Children and Youth. In 2009, the latest data available, there were 29.6 pregnancies per 1,000 girls, down from a rate of 48.2 in 1998.

Yet the state's teen pregnancy rate remains one of the highest in the nation, according to the New York-based Guttmacher Institute, a reproductive health research organization.

Elizabeth Nash, state issues manager for the institute, said state lawmakers across the country began considering more comprehensive sex education programs that talked about abstinence, but also included contraception, about 10 years ago.

Despite declining pregnancy rates around the country, Nash said, there's been a shift by states over the past two years to promote abstinence-only education. A Utah bill that would have prohibited any discussion of contraception or homosexuality in sex education classes passed the Legislature but was vetoed by the governor.

"Our perspective is that comprehensive sex education is appropriate and necessary for young people," she said.

"What we know ... from the research is that comprehensive sex education works. It delays sexual activity, it reduces the number of partners teens have, and it increases contraceptive use. There is very little in the way of any rigorous research that shows that abstinence education has any of these long-term benefits."

Barry Chase, president of Planned Parenthood Greater Memphis Region, agreed.

"This bill ties the hands of educators in Tennessee and will prevent them from providing the comprehensive education that students want and need and their parents expect," he said.

Rep. Jim Gotto, who sponsored the legislation, disputed the way the bill is being characterized.

"It's not abstinence-only education," said the Nashville Republican. "I'm so sick of people trying to spin it as that ... because they don't like it. The law does specify that the curriculum has to be abstinence-focused, but they can talk about contraception."

Proponents contend abstinence is the most reliable way to prevent pregnancy and sexually transmitted diseases. Tennessee education officials have said abstinence is already defined in the state's statute, and Haslam said he decided to sign the bill after they assured him it changed little.

But Sen. Jack Johnson, a Franklin Republican who sponsored the bill in his chamber, said the old law was too vague.

"We put in tighter definitions, more clearly defined what abstinence-centered and abstinence-based meant," Johnson said.

The sex ed law now uses the criminal statute on sexual assault to specify acts — such as groping or fondling — that fall under "gateway sexual activity." It also says family life curriculum must not "display or conduct demonstrations with devices specifically manufactured for sexual stimulation." If such incidents do occur, then a parent can sue and a fine can be imposed of at least $500.

Before the current law, Nashville parent Rodrick Glover thought about legal action in 2010 when he found out an anti-AIDS group had visited his 17-year-old daughter's class and demonstrated safe oral sex with a sex toy and a condom.

"I teach my child the power of abstinence," said Glover, whose complaint spurred the drafting of the legislation. "When you start bringing sex toys in, at a point you're stimulating the kids to have sex."

The leader of the group whose presentation concerned Glover agrees the material was inappropriate for a high school audience. He said the incident led to new procedures to adhere to school protocols.

"And we've had no problems for two years," said Joseph Interrante, president of Nashville CARES.

Valerie Huber, executive director of the National Abstinence Education Association, said Tennessee is ahead of most other states and has closed a loophole.

"I think that is unique in that rather than this legislation just saying there needs to be an emphasis on abstinence education, it also prohibits too explicit sex education from being either put in schools under the guise of abstinence education, or in opposition to an abstinence education program," she said.

Democratic Rep. John Deberry supported the new limits on what can be covered in sex ed class as a way to help teenagers from going too far.

"When individuals are touching one another's intimate parts ... this is sexual activity that has its ultimate goal of penetration," said the Memphis Democrat and minister.

Student Josiah Pegues, 14, of Nashville said he's already made up his mind about sex — for now, at least.

"It's best to abstain," said the ninth-grader who aspires to be an FBI agent. "You don't want to get anyone pregnant or get an STD. It could mess up your future."