Teens are seldom honest about serious sexual-health matters

A physician who specializes in adolescents used to joke about teens' honesty when asked about sex. "How do you tell if a teen is lying?" he would ask. "Their lips are moving."

A novel national study published last year in the journal Pediatrics demonstrated the disconnect between the sexual behaviors teens report and their test results showing STDs. Among more than 14,000 young adults, 10 percent had STDs even though they insisted they hadn't had sex in the previous 12 months. More than 6 percent who tested positive reported never having sex at all.

What's going on?

Many STDs if caught early can be treated without serious aftereffects, such as infertility and pelvic inflammatory disease. Interventions for lifelong diseases such as HIV and herpes can be addressed much earlier, before the body's immune system is irrevocably damaged. The problem is that many STDs are asymptomatic, easily transmitted, and go unrecognized.

The most recent National Youth Risk Behavior Survey, in 2009, supplied us with some disturbing facts. More than 25 percent of teen females older than 14 have been diagnosed with an STD; 39 percent of teens did not use condoms the last time they had sex; and nearly half of the 19 million newly diagnosed STDs are among people ages 15 to 24.

In Philadelphia, the rates are much worse. Among the city's high school teenagers, 63.5 percent have had sexual intercourse; an astonishing 14.5 percent had their first sexual encounter before age 13. A little more than 25 percent have had more than four sexual partners, and 11.1 percent drank alcohol or used drugs before their last sexual encounter.

It's no wonder Philadelphia teens have some of the highest STD rates in the country. More than 19,000 cases of chlamydia were reported in 2010, 45 percent of which were in people ages 10 to 19. Those numbers include only cases reported by health-care providers or laboratories. Many more go undiagnosed.

So why are teens not candid about their experiences? Consider the teen brain.

An important concept behind teen risk-taking is the internal struggle behind teenagers' furrowed brows.

Deep within the core of the brain is the limbic system, which matures earlier and plays a central role in emotional responses. The prefrontal cortex, the "control center" of the brain, matures later. This development explains why teens often choose emotions and instant gratification (limbic system) over logic and self-control (prefrontal cortex). They tend to be as logical as adults until they are around peers or become emotionally aroused. Then they can lose their ability to regulate their cognitive control network and can succumb to their emotions. This is why many teens make poor decisions when in groups, under the influence of their peers or flush with emotion.

Parents and caregivers should be teens' most important sexual educators. Parents need to start early (no evidence exists showing that talking about sex with a child will encourage experimentation), and talk about sexuality when an opportune moment arrives. A good resource for advice is the Kidshealth website (www.kidshealth.org).

For health-care providers, counseling should emphasize the most reliable and realistic ways to reduce infection, including abstinence, the use of condoms and dams during each sexual encounter, and the promotion of mutually monogamous relationships with uninfected partners.

Clinicians also need to emphasize the concept of cumulative risk: Even if patients do not use protection during one sexual encounter, they can still reduce their overall risk by using protection during future encounters.

Also, in November 2011, the American Academy of Pediatrics adopted the 2006 CDC recommendations for universal and routine HIV testing for all patients 13 to 64. This advice springs from the increasing HIV/AIDs prevalence in the United States and the missed opportunities for HIV testing. In 2006, an estimated 48 percent of HIV-infected adolescents and young adults were unaware of their infection. In the zip code of St. Christopher's Hospital for Children - 19134 - there were 405 cases of HIV, second only to the cases in 19136, which includes Holmesburg Prison.

Nonjudgmental behavioral counseling helps prevent STDs, along with routine screening for STDs and HIV. Teens and their families can access resources such as Take Control Philly (www.takecontrolphilly.org), the CHOICE Hotline (www.choice-phila.org), and Cap4Kids (www.cap4kids.org/philadelphia).

Teens have incredible talents, strengths, and potential. Those who care for them just need to watch their moving lips a little more closely.