The poster features an abstract characters catching sperm with a condom net, like butterfly catchers, alongside the line "Make sure sperm is the only thing you catch. Use a condom".
The illustrations were by Polish artist Ziemowit Maj.
The activity is an extension of the "It's your choice strategy" and was researched with young people before launch.
The campaign will roll out on 48-sheet posters nationwide, with support from postcards and a , throughout 2008.
Simon Blake, chief executive of Brook, said: "Brook is committed to campaigning around young people's sexual health in an innovative way and I'm delighted to be working with Feel on this campaign. It's a bright and humorous way to encourage young people to think about safer sex."
Chris Arnold, creative partner at Feel, said: "Taking a fun graphic approach has proven to be a more effective way to communicate serious issues to youth.
"The campaign is designed to inform and remind, not lecture. Before young people can take responsibility they need to have an informed choice. "
Chlamydia is the commonest sexually transmitted infection in the UK and is on the increase. It rose by 252% between 1995 and 2006 to 113,585 cases reported.