Young people fear that e-mail and mobile phones make it too easy for their partners to cheat on them, according to new research.
Young people think technology makes it easier to be unfaithful
More than 60% of 18 to 24-year-olds said they were scared technology increased opportunities for infidelity with people able to flirt secretly.
Over 90% thought both sexes should share responsibility for contraception.
ICM interviewed 1,008 people for the Family Planning Association to coincide with Contraceptive Awareness Week.
More than a third of young people believed that racy TV shows such as Sex and the City encouraged people to be less responsible about their sexual health.
And over 90% said their relationship with their family was the most important in their life.
Some 69% thought sex was more fun now than in times gone by.
But only 61% thought the pill had liberated women compared to 82% of 55 to 64-year-olds asked.
While 77% of over-75s thought emergency contraception was a real benefit to women, 63% of young people thought the same.
Association chief executive Anne Weyman said the study showed that young people thought carefully about sex and relationships.