Reported by Dr. Lauren Browne:

Let's face it. Teens have sex. Parents may choose to ignore it, and teens may choose to deny it, but almost 50 percent of American high school students are having sex, according to the U.S. Centers for Disease Control. And each year, millions of those sexually active teens contract sexually transmitted diseases such as chlamydia, gonorrhea, syphilis, herpes and HIV.

Now one doctor hopes to curb the spread of STDs in this tech savvy group with a smartphone app that lets users "bump" their STD status.

It's called 'safe bumping,'" said Dr. Michael Nusbaum, the New Jersey developer of MedXSafe, a feature of the new app called MedXCom. "If you happen to be out at a bar or a fraternity house or wherever, and you meet someone, you can then bump phones and exchange contact information and STD status."

The app's special feature, according to Nussbaum, encourages dating singles to go to the doctor for regular STD checks. Those who screen negative can ask their doctors to document their STD-free status on the app, allowing users to share the information with whomever they choose.

An alarming 19 million new sexually transmitted infections occur each year, and rates of chlamydia and gonorrhea are on the rise, according to a new report released this month by the CDC. More than 1.4 million chlamydia infections were reported in 2011, up 8 percent from the previous year. Cases of gonorrhea were up by 4 percent, marking the second consecutive year of increases.

Nearly half of all infections occur in young people, between the ages of 15 to 24, a group that can be particularly devastated by the associated health effects.

"[Some] undetected and untreated STDs can increase a person's risk for HIV and cause other serious health consequences, such as infertility," said Mary McFarlane, an acting chief in the Division of STD Prevention at the CDC. Harnessing modern social networking technology to prevent these infections may appeal to a younger tech-savvy generation.

MedXSafe is just one of several Internet-based programs devoted to easing confidential STD-status sharing between sexual partners. Services like Qpid.me, whose slogan is Spread the Love, Nothing Else and U Should Know, designed by a former college student and his girlfriend, also allow their users to check on a partner's STD status.

But could these services offer a false sense of security to teens who believe that, with a simple phone bump, they have the green light to have unprotected sex?

"It can take months for HIV to show up on a test," said Renee Williams, executive director of SAFE, a nonprofit organization dedicated to abstinence education. "So you can test negative today, go out on Friday night and have sex, and then get retested later and find out that you had HIV all along."

The app does nothing to prevent unplanned pregnancy, and may even encourage high-risk behaviors that young people might otherwise not have been tempted to try, said Williams.

Nor is the app likely to be completely reliable, said Dr. J. Joseph Speidel, director of communication at the Bixby Center for Global Reproductive Health.

"Does it come with a condom?" asked Dr. Richard Besser, ABC's chief health and medical editor, who's also a pediatrician and former acting director at the CDC.

But the app's creator said it does promote regular STD testing and encourages potential partners to openly discuss safe sex practices.

"We're recognizing that this behavior is going to take place no matter what we do or what we say," said Nusbaum. "I have friends that are nuns and I've run this by them, and they also agree that it's promoting safer behaviors."

Although each program promises to keep health information strictly confidential, none are immune from cyber attacks.

But such attacks would not expose any users who have an STD, according to Nusbaum. MedXSafe does not allow doctors to upload information about any tests that come back positive, including HIV. A user with an infection is simply treated for the STD and then retested. And that user is only confirmed STD-free via the app once subsequent test results come back negative.

Still, it is too early to tell whether these services will become popular with teens. Lingering social stigma surrounding STDs might make potential partners reluctant to mention such an app when out at a party.

"It's a big personal step to bring up using such an app," said Noah Bloom, creator of a smartphone app called Jiber, which uses the same "bump" technology to electronically connect new friends. "Who really wants anything in the way of getting lucky?"