The stress of modern living is taking a toll on people's sex lives, a psychosexual therapist has said.
A BBC Radio 5 Live online survey questioned 2,066 UK adults about their attitudes to sex and relationships.
Stress was rated as a problem in the bedroom by more people than any other factor (45%).
Relate therapist Ellen Brady said: "We're seeing an awful lot of clients with anxiety issues - anxiety and sex just doesn't sit together at all."
Other factors highlighted by respondents as having a negative impact on sex included physical health problems, mental health issues, and having children.
Only 10% of respondents highlighted social media as a problem.
However, Ms Brady said it probably had a bigger impact than most realised.
"There's not the basic connection happening in couples, they're not even making eye contact or talking to each other, so it's no wonder when they get to bed that sex is difficult."
Overall, half of those questioned said they were satisfied with their sex lives (50% of men and 53% of women).
However, 38% of men and a quarter of women said they were not satisfied with their sex lives.
The survey suggested 58% of people are generally confident about their sexual performance.
Is it cheating?
The survey suggested men and women take a different view on cheating.
Three-quarters of women said they considered a partner paying for an online experience (such as cyber sex) and kissing someone other than their partner to be cheating. But only half of men said the same.
Nine in 10 UK adults (91%) said that having sex with someone other than their partner was cheating, but only two in five (40%) said browsing on a dating app was being unfaithful.
So how can you improve your sex life?
Ms Brady from Relate suggests putting a temporary ban on sex, and starting again: "Ban sex, because whatever you've been doing sexually it's gone wrong, so you want to wipe it out and start again, and just reconnect emotionally and in terms of intimacy."
"There's a big gender divide on that one, because women very often want to buy into emotional intimacy and kisses and cuddles and quite often men don't see that as a priority, they see sex as the priority.
"However in my experience it doesn't take very long for men to actually realise that that's what they want too... and of course it leads them on to sex anyway because that creates the right conditions for sex to happen."
BBC Radio 5 Live is hosting a Sex Takeover, a day of programming focused on our sexual behaviour, relationships and attitudes, on 20 November 2018.