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Sex, condoms, and STDs: CDC warns about teen risk behaviors
The CDC's latest youth risk survey houses some scary numbers but shows that evidence-based sex education is working.

It's a well-worn truism that teenagers take risks—whether its drugs, drinking, shoplifting, or drag racing down the L.A. River against their 30-year-old gang rivals. On the flip side of that truism, parents worry endlessly that those risks will result in life-altering consequences. And there's perhaps no risk more fraught with worry than when and how teenagers will become sexually active.
Boys and girls begin puberty early in their teens, an age established during our 200,000-year evolutionary history. Yet, this time frame is horribly mismatched with modern cultures and societies. Today's teenagers reach psychosocial maturity much later and build life plans centered on long-term education and career goals. Thankfully, in the 20th century we developed safe, effective contraceptives and prophylactics, granting us a chance to find harmony between our modern realities and evolutionary drives.
But do teenagers engage in safe sex, or are they taking unnecessary risks during their first sexual escapades? That's the question the CDC hopes to answer with its Youth Risk Behavior Surveillance System. This biennial, nationwide survey aims to monitor health-related risk behaviors among high school students. And when it comes to sex, the survey's findings are both promising and a tad terrifying.
Are the kids alright?
A graph showing the prevalence of condom and primary contraceptive use among high school students during their last sex act.
First some good news: About 90 percent of sexually active high school students report using either a condom or other primary contraceptive method. Condoms were the most used form of contraceptive, with about half of that cohort claiming to have used one during their previous act of intercourse. Sexually active students made up about a quarter of all respondents, meaning more adolescents are choosing to wait until at least their late teens to have sex.
Looking at long-term data, today's teenagers make better decisions than their '90s peers. When the survey began in 1991, more than 50 percent of respondents claimed to have engaged in sex at least once. Of those, 16 percent said they used no method of birth control while 10 percent said they had sex before the age of thirteen. In 2019, 38 percent of respondents claimed to have had sex at least once. Of those, only 12 said they used no birth control while 3 percent said they had sex before thirteen.
Overall, the CDC reports adolescence to be a healthy stage in people's lives.
Now for some bad news: Condom use among sexually active teens has decreased. While 2019's 54 percent represents an uptick from the 1990's, it is a headlong drop from 2003's high of 63 percent. Granted, condom use may be underestimated due to survey limitations. For example, respondents could only select one birth control method for their latest sexual act. This means they could have considered another method as their primary birth control while leaving condom use unaccounted for. Even so, 2019's tally still suggests too many teenagers take unnecessary risks with pregnancy and STD transmission.
Other troubling figures also emerged. About a fifth of sexually active teens report using either no contraception or using a highly ineffective method, such as withdrawal. Only 9 percent report pairing an effective birth control with a condom. That figure may also be underestimated as half of the respondents were teenage boys, who—let's face it—may not have the most reliable grasp on female contraception use.
Teenagers and people in their early 20s represent about half of the 20 million new cases of STDs each year in the U.S. So, while 90 percent of sexually active teenagers may be protecting themselves from unintended pregnancies, many still risk their health in other ways. This is why experts recommend teens pair a condom with an effective birth control. It provides extra protection from unintended pregnancy while adding a prophylactic element to hinder the spread of STDs.
Having the talk
What can be done to bolster positive trends and reverse negative ones? Continue advancing sex education and outreach programs. In the survey, the CDC notes the proven effectiveness of risk reduction education—that is, not fearmongering but comprehensive, evidence-based teaching.
Unfortunately for adults hoping to avoid awkward conversations with banana stand-ins, this means doing away with abstinence-only programs. A review of the scientific literature found that these programs contain "scientifically inaccurate information, distort[ed] data on topics such as condom efficacy, and [promotion] of gender stereotypes." It concluded that abstinence-only programs put teens at greater risk of unintended pregnancies and STDs. With the gap between sexual maturity and marriage ever-widening, such programs, no matter how well-intended, are simply unrealistic.
As Laura Grubb, author of the American Academy of Pediatrics guidelines on adolescent barrier protection, told CNN:
It does not have to be a controversial position. There is no evidence that providing contraception to adolescents makes them more sexually active or promotes risky behavior. […] In fact, comprehensive evidence-based sexuality education results in adolescents delaying sexual behavior, using contraception at first intercourse, and having less sexual partners at a young age."
The CDC also recommends strong partnerships between communities and clinics. Teens should have access to well-trained care providers to provide the information and services they need.
Sex comes with risks, and it is impossible to reduce a teen's risk factor to zero. That's not necessarily a bad thing. Risk-taking is how teenagers develop their independence and form the identities that will carry over into their adult lives. It helps them experience qualities of the world that were hidden to them as children. But without comprehensive education, the consequences of those risks may stay hidden until it's too late. And without access to proper outreach and resources, they may not have the means to mitigate those risks.
As for drugs, drinking, shoplifting, and drag racing down the L.A. river for pinks, those are topics for other surveys and articles.
- How Tribalism Overrules Reason, and Makes Risky Times More ... ›
- Risky Business: The Effect of Peer Pressure on Virginity Loss - Big ... ›
- Poor Memory May Predict Sexual Risk-Taking in Teens - Big Think ›
How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTA0Njk2OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyMzM2NDQzOH0.rid9regiDaKczCCKBsu7wrHkNQ64Vz_XcOEZIzAhzgM/img.jpg?width=980" id="2bb93" class="rm-shortcode" data-rm-shortcode-id="31345afbdf2bd408fd3e9f31520c445a" data-rm-shortcode-name="rebelmouse-image" data-width="1546" data-height="1056" />Northwell emergency departments use the dashboard to monitor in real time.
Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
World's oldest work of art found in a hidden Indonesian valley
Archaeologists discover a cave painting of a wild pig that is now the world's oldest dated work of representational art.
Pig painting at Leang Tedongnge in Indonesia, made at 45,500 years ago.
- Archaeologists find a cave painting of a wild pig that is at least 45,500 years old.
- The painting is the earliest known work of representational art.
- The discovery was made in a remote valley on the Indonesian island of Sulawesi.
Oldest Cave Art Found in Sulawesi
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a9734e306f0914bfdcbe79a1e317a7f0"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/b-wAYtBxn7E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
