SIMPSONVILLE, S.C. -- Teens who take a pledge to abstain from sex until marriage are no less likely than their peers to actually refrain from sexual activity, according to a study published Monday.

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Also, those teens are more likely to engage in sex without protection from disease or pregnancy, the research by Johns Hopkins University indicates.

The study by Johns Hopkins researcher Dr. Janet Elise Rosenbaum was released in the January edition of the Journal of the American Academy of Pediatrics.

The findings come as no surprise to Mandy Black, founder of the Little Steps mentoring program in Simpsonville, S.C.

Little Steps was developed as a place where pregnant teens and young parents can find a sympathetic ear and advice from someone who's been there.

"We have a big belief here in being real about these kinds of things," Black told WYFF-TV.

Black said she was unmarried when she had her first child at 18 -- after taking the pledge.

"I was heavily involved in an abstinence program through our church -- right before I got pregnant," Black said.

The Johns Hopkins study compared the attitudes and behavior of about 1,000 high school students who had taken a virginity pledge to those who hadn't.

Researchers said that they found no significant difference in sexual activity, including the number of partners or the age at which the teen lost his or her virginity.

The study also found that teens who had taken a virginity pledge were less likely to use condoms or other birth control.

Black said that she understands the appeal of abstinence programs and that many parents fear sending a mixed message by encouraging abstinence but still talking about birth control.

"We'd like to think the morality of it and that sort of thing is enough," Black said. "I think if we are not being real about the fact that teens are tempted with this, then we are missing the boat."

Lauren Kramer, a teen mother and visitor to Little Steps, said that peer pressure is stronger than ever.

Kramer said she adores her 11-month-old son but still preaches the virtues of abstinence to anyone who will listen.

"Once you lose your virginity, you've lost it, you can't gain it back," Kramer said. "Once you have a child, it changes everything. No more going to the mall, having fun."

Both Kramer and Black said that they believe morality taught at home is the most powerful lesson, but that just making a pledge isn't enough.

Previous studies have shown some success among abstinence programs.

Attempts to contact the pro-abstinence organization True Love Waits were not successful on Monday.