Everyone knows about the seven-year itch. But what about the 17 (or 27) year itch...? After decades together, it's easy for sex to become an occasional chore, rather than the exciting, intimate experience it once was.
Luckily, you don't need a trunk full of props to get your mojo back. In fact, 'orgasm is easier when we feel secure, which is more likely with our regular partner,' says Harley Street Psychotherapist Diana Parkinson. 'It's all about feeling that familiar comfort along with desire.'
Here's how to revamp your sex life. (No feather boas required.)
1. Get out of bed
While sex in bed can be cosy, it's no wonder you end up going through the same old motions. Breaking a habit together means seeing each other afresh, so surprise him with the offer of a quickie in the kitchen, or turn your Saturday night on the sofa into something more interesting than 'pass the Pringles'.
It can feel awkward at first, but once you're kissing, you may as well carry on. 'Even getting out of the house can help,' says Alix Fox, sex and relationships expert for Durex. 'Go for a walk, and find a quiet spot somewhere to kiss. The small act of going out and coming back refreshed can help change the mood.'
2. Learn something lovely
Doing something different is usually a solo enterprise, whether it's book group, choir or running.
But doing it together gives you a different perspective on each other's skills and talents. It's easy to take each other for granted and find one another predictable when you know each other inside out.
So sign up for a course in pottery, tango or languages (try sexy Italian or French) and you'll see a different side of each other - which can easily translate into renewed attraction. 'Once we settle into a partnership, it shouldn't be the end of our personal development – just the beginning,' says Diana.
3. Focus on feeling
It's easy to let worries about your middle-aged spread put you off making love. But in a long-term partnership, looks may fade, but sensation doesn't have to.
'Lots of us have a tendency to get too hung up on how we look during sex, and forget to be truly mindful of how we feel, in ourselves and to our partners,' says Alix. Focus on the feeling of being together, rather than fretting about your flabby bits.
If you feel more comfortable with the lights off, that's fine. Just holding each other and seeing what happens is much more likely to lead to great sex than panicking because you can't squeeze into your best lacy knickers.
4. Keep quiet
Often, when you haven't seen your partner all day it's tempting to offload your worries. But a list of money problems, topped off with carping about how much weight your partners' put on is not going to get you both in the mood for anything beyond a mild sulk.
'NEVER comment on flabby bits!' agrees Diana, 'Real sex is happy to accommodate our bodies in all their hairy, wobbly wonder." And don't criticise your own body, either, adds Alix: 'Your partner is sure to find an upbeat, self-respecting attitude more alluring than moans about your thighs.'
5. Make one small change
If you're in a rut, your sex life won't change until you do. But you don't have to move to Canada and train for a marathon. Just one small change in behaviour can be enough to reboot your lagging libido.
And there's one other thing you can do, says Alix:'Durex recently commissioned a study into the impact that technology is having on romantic relationships, and 40% of people interviewed had delayed sex because they were preoccupied by smartphones.' High time to ban it from the boudoir.