Many students are "completely clueless" about condoms and birth control, according to a poll released yesterday.

More than one in 10 cannot put a condom on properly and 16% believe two condoms are safer than one. More than a third of students believe condoms have holes in them big enough for HIV to get through.

The survey of more than 2,200 university students, carried out for the Terrence Higgins Trust and the National Union of Students, involved 20 questions about condoms. Lisa Power, the charity's head of policy, said: "University students are no smarter than many other young people when it comes to sexual health.

"They are just as likely to believe myths about condoms and to have got more of their sex education in the playground than the classroom.

"We spend a fortune educating students, but leave them ignorant about key issues in their adult lives. It's hardly surprising that rates of sexually transmitted infections are soaring."

The charity wants sex and relationships education to be made compulsory in schools, rather than the present situation where students may only be taught the biology of conception. It has gathered more than 5,000 signatures on the issue.

Veronica King, the NUS vice president of welfare, said: "These results are a timely reminder of the value of good sex education and clearly many more resources are needed to improve awareness."

A Department for Education and Skills spokeswoman said: "The elements of sex education as set out in the national curriculum for the teaching of science are compulsory in all maintained schools."