1 Time to explore

This may come as a surprise but it takes years to get really good at sex. In fact, the award-winning, much-celebrated sex guide Enduring Desire (by marital and sex therapists Michael Metz and Barry McCarthy) points to research that found that the best sex occurs in couples who have been together for 15 years or longer!

“In a one-night stand, in short-term relationships, sex can be more of a ‘performance,’” says Mike Lousada, a psychosexual therapist. “You show the ‘edited highlights’ and you go away at the end not knowing for sure what your partner experienced. ‘I’m here for a few hours, I’ve got five good moves and here they are!’”

2 There’s no pressure

STIs. Does she really like me? Is he weird? When was my last wax? Which pants am I wearing ? Sex outside committed relationships can come with a heap of anxieties and there is no greater turn-off than anxiety. “For women especially, if you’re distracted, if you can’t relax, it’s hard to enjoy sexual pleasure and experience orgasm,” says the clinical sexologist and relationship coach Uta Demontis. In a marriage or a long-term, committed relationship, those pressures lift and hopefully you’ve got your contraception sorted out too. “When you can finally put all those worries aside, you’re free to focus on enjoying yourself,” says Demontis.

3 You can experiment

“Trust is so important when it comes to sex,” says the psychotherapist Simon Jacobs. “The more you trust your partner, the more able you are to be fully yourself. The sexual act is one of the few moments where you let go of your inhibitions so it’s a vulnerable place to put yourself.” Kink. Taboos. If you feel safe, you’re less inhibited. “Good sex is about being able to play again, be silly, get messy,” says Jacobs. “Transgressing boundaries when you are Mr and Mrs Normal living a structured, routine kind of life – that’s where the contrast can get really interesting.”

3 You can experiment

“Trust is so important when it comes to sex,” says the psychotherapist Simon Jacobs. “The more you trust your partner, the more able you are to be fully yourself. The sexual act is one of the few moments where you let go of your inhibitions so it’s a vulnerable place to put yourself.” Kink. Taboos. If you feel safe, you’re less inhibited. “Good sex is about being able to play again, be silly, get messy,” says Jacobs. “Transgressing boundaries when you are Mr and Mrs Normal living a structured, routine kind of life – that’s where the contrast can get really interesting.”

5 You can have quickies

Every encounter isn’t charged with expectation – sex doesn’t have to be an event every time. You know each other’s shortcuts and each other’s bodies. You can do it fast, then move swiftly on to discuss the broken dishwasher or what is for tea. “You can have ‘great sex’ and ‘good enough’ sex and sex that doesn’t really leave you physically satisfied – but all of it nurtures intimacy,” says Waring. “Not taking sex really seriously and being playful is important in a marriage. I think it’s fantastic when a couple can say, ‘I fancy one.’ ‘Well, OK, but Match of the Day is on in 15 minutes.’”

6 … and sneaky ones

As life moves on, if children arrive, you are grown-up, respectable – and rarely alone. You may have to seize the moment and take your chances – and that’s fun, says the psychotherapist Christine Webber. “If you know your children are out every Saturday morning, you wave them off, close the door and make the most of it before they get back. Or you have a teenager awake upstairs who would be horrified to know what you’re up to, so you have to be quieter – all that can be pretty powerful! It’s the same as being a teenager and taking a chance when your parents are out of the room. It feels illicit – and it’s also often funny. My husband (the author and media doctor Dr David Delvin) once wrote ‘Laughter is worth 1,000 orgasms.’ I’m not sure I’d go that far but it’s certainly up there!”

7 Sex is on tap

“Sex serves all kinds of purposes,” says Webber. “It can be very restorative. You can have consoling sex after a disappointment or healing sex after a horrible row. You might have sex to comfort your partner after a really bad day or distract yourself at a difficult time.”

The point is, when you’re married, it’s always possible. “I imagine, in times like these, sex is helping a lot of couples,” says Webber. “As the world seems to be unravelling before our eyes, it’s the best way of de-stressing, and of bringing that sense of safety, of belonging somewhere and having someone when times are frightening.”

8 You remember each other’s bodies at their best

“There’s something about someone making love to your body when it’s not the body it once was,” says the psychotherapist Wendy Bristow. “I’m not just talking about ‘oldies’ – you can be 35 and have just had a baby. Even if your confidence and self-esteem are fine, we all have certain bits of our bodies we’re not happy about. You may not be consciously turning a blind eye to your partner’s extra bumps and lumps and wobbly bits, but when you marry someone and the years pass, there’s still a sense that you’re making love to the person you first made love to. You hear it when an elderly man says of his wife, ‘She’s still the girl I fell in love with.’ Carrying that sense of who you both were can be wonderful.”

9 Postcoital moments mean much more

In one-night stands and short-term relationships, it can be awkward, icy or absent. In a loving marriage, it’s the icing on the cake. Christine Webber has just written a novel, Who’d Have Thought It?, about a middle-aged woman who finds herself single again after a long marriage. She finds exquisite sex and excruciating sex, but what she wants is love and marriage.

10 Celebratory sex

It’s the kind of sex that means so much more in a long marriage. An anniversary. Your son’s graduation. Your daughter’s wedding. A brilliant family holiday. “It’s really more than sex, it’s celebrating your whole story together, your appreciation of one another and what you’ve both built,” says Wendy Bristow.