About 7.4 percent of teenagers in Washington, D.C.’s public and public charter high schools has exchanged sex for money, drugs, or something else of value.

The finding comes from a Centers for Disease Control and Prevention (CDC) study co-authored by Sara Head, an epidemiologist with the D.C. Department of Health. She presented her findings at a conference in Atlanta earlier this month.

It’s the first study to quantify exchange sex rates among young people in D.C., according to the authors.

Head noted that certain groups were more likely to have exchanged sex than others. In particular, students who had been kicked out of their homes, run away, or been abandoned in the past 30 days were 11 times more likely to have exchanged sex. The practice puts teenagers and adults at higher risk for HIV and sexually transmitted diseases.

Odds of exchange sex were also higher among boys than girls and among students who were sexually active with partners of both sexes. Students who had gone hungry in the past 30 days or who had ever used synthetic marijuana, cocaine, heroin, methamphetamines, or ecstasy also had higher odds.

The study concludes that D.C. programs that provide services to youth with unstable housing, food insecurity, or who use drugs “should consider incorporating sexual health services to address exchange sex practices.”

That conclusion was “a bit of a no-brainer moment to me,” said Cyndee Clay, the executive director of HIPS in Northeast D.C. Her organization supports people impacted by sex exchange and drug use, and she said her team has always been particularly focused on the resources and care they give to young people.

“When youth have breakdowns in support systems, that’s often when they turn to exchanging sex to survive,” Clay said. “The question is, do these youth have the education to protect themselves?”

Clay said she has seen improvements in how the D.C. public school system addresses at-risk youth. City schools teach a comprehensive sex education curriculum and educate staff on how to help LGBTQ youth feel accepted and safe.

“The District takes the safety and well being of our youth extremely seriously,” said Paul Kihn, the D.C. Deputy Mayor for Education, in a written statement. “Mayor Bowser and our whole administration have made it a priority to expand preventative safety measures to protect students and vulnerable populations.”

The D.C. Department of Health also has a number of programs in place to address HIV risk among young people, including school-based STD screenings and free condoms in nurses’ offices.

But Clay says the city’s number one concern should be getting kids in stable housing.

“Housing is a big deal,” she said. “While we’ve made strides in the city in improving housing access for young people, we have much farther we could go.”

The population of homeless children has been increasing in D.C., according to attorney Amber Harding of the Washington Legal Clinic for the Homeless.

“The number of homeless children in D.C.’s schools has increased 26 percent since 2015, doubled since 2014,” Harding testified at a D.C. Department of Human Services performance oversight hearing on March 1, according to the Washington City Paper.

“Students turning to trading sex for survival needs is a stunning failure of the District of Columbia to aid the youth who need our support most,” said At-large D.C Councilmember David Grosso in a statement on Thursday. He added that the inclusion of additional funds in the FY20 budget “to support homeless youth and provide greater access to food” was a start.

Kihn also noted that D.C. Mayor Muriel Bowser’s proposed budget includes a number of increases for wraparound services for vulnerable populations, including a $6 million increase over FY19 for school mental health services and $130 million (a $30 million increase over FY19) for the Housing Production Trust Fund, which creates and supports affordable housing in the District.

The study data comes from the 2017 Youth Risk Behavior Survey, which included 8,578 students in grades 9 through 12. The D.C. government administers the anonymous survey to middle and high school students every two years.

Students were asked if they had ever been given money, a place to stay, food, or something else of value in exchange for sex.

“It’s not a question that’s frequently asked in surveys,” Head said. She noted that approximately 5 percent of people aged 11 to 27 years in the United States have exchanged sex, but she is unaware of similar research from other comparable cities or jurisdictions on exchange sex rates among youth.

“We really don’t know how D.C. might compare to other places, or how it might compare nationally,” she said.

This story originally appeared on WAMU.