Unlike Nick Clegg – who told an interviewer last week that he’d slept with up to 30 women – most girls know exactly how many men they’ve slept with and can even name many of them. And unlike Nick Clegg we’ll never, ever, go on the record about it.

Never. No, even though I will admit something very different to my girlfriends during an intimate chat, for the record: I’m a virgin.

And as I’ve never slept with anyone, it follows that I’ve never slept with Nick Clegg, but this time last year I should admit that I did have dinner with Piers Morgan – yes, the very same Piers whose questioning of the new Liberal Democrat leader has led to the insertion of the hilarious word “Cleggover” into practically every conversation I had last week.

I could have warned Clegg about Piers. As an interviewer Morgan specialises in rummaging around in his victims’ intimate past, just as you or I might fish into the sink and triumphantly remove a disgusting bolus of hair and gunk from the plughole. He doesn’t just do it for magazines either, but in private too. At our dinner, over steak and Barolo, I was cheerily off guard and in my cups when Piers asked: “So who’ve you shagged then?”

Since I am, of course, a virgin, my reflexes kicked in and I ducked the question like an incoming mortar shell. Why? One, because anything Piers says to me, or I say to him, is assumed to be copy, and I don’t want the details – especially not the boring and blameless details – of my sex life available to all. Two, it’s private, Piers. And, three, no woman, let alone a female political leader, would reply to a “how many?” question, let alone in forensic detail, even when drunk. But a male leader would, and did.

So this is how the conversation went. Piers Morgan: “How many women would actually know for a fact if you’re good in bed?”

Nick Clegg (after some spluttering): “No more than 30.”

What’s interesting here is that Clegg answered the direct question at all – and not what he said, which was not shockingly excessive but boringly average.

In 2005 a survey by a psychologist, Norman Brown of the University of Alberta, found that men reported an average of 31.9 partners. When asked the same question women reported an average of 8.6 partners. To explain this bizarre discrepancy experts resort to the conclusion that men like to present themselves as sexual conquistadors, continental boulevardiers, coureurs or any of the other strange foreign words we English reach for when it comes to men and sex. And women present themselves as restrained and picky when it comes to sexual partners.

The truth is probably somewhere in between. Clegg has been accused of counting notches on the bedpost, but what he said sounded to me not only open and modern and Lib Demish but also . . . rather modest for a man.

After all, if you think that today teenagers start being sexually active at the age of 16 and the marrying age is 29 for women and 31 for men, well then, having 30 or fewer sexual partners (a measure henceforth known as “a Clegg”) is not promiscuous; it’s continent. It’s two a year. It’s one partner for every six months of your unmarried life. Which isn’t that excessive, is it?

Even so, this is clearly not a strike rate that women admit to in surveys. So all the Cleggover saga tells us in the end is that there is a continuing double standard about sex, exactly 45 years after the invention of sexual intercourse in 1963. A male, a party leader and a public figure, and not even a mate of Piers, can dish about his sexual past for a public interview, but a female won’t, not even in a semi-private conversation.

I myself would prefer it if people didn’t, on the whole, talk about their sex lives at all very much, especially public figures, but simply get on with it in private, because it fills the mind with such fruity and unpleasant images. Frankly, I don’t want to go there.

It’s interesting to note, though, that if asked a direct question, men are still tempted to give a direct answer about their sex lives, and to exaggerate, while a woman’s instinct is almost always to lie – as if there were a right or a wrong amount of sex that anyone could have, which is never the case.

There’s rarely too much sex in our lives, as John Betjeman for one was brave enough to admit – there’s generally not enough. So why are we women so wary about admitting what we get up to?

***********************************

Once every few years I get up on a big horse. It’s to do with thinking I should be the sort of woman who can subdue 15 hands of rippling sinew with her inner thighs, who looks good in black jodhpurs, who enjoys a good gallop and all those horsey, hearty things. Anyway, after about 20 minutes or so I fall off.

When I fell off last week, all that happened was the same as the last time it happened. I had simply and non-verbally conveyed to my mount the same fatal lack of authority as I do to my children. The horse decided he didn’t want to do it my way, but to do it his way, and cantered off. I lost a stirrup, then lost the reins and finally toppled gracelessly into the soggy heather of high Exmoor, miles from home.

Then – a blank. Luckily I was with an expert horsewoman, Charlotte, who galloped after Winston, and bore him back to me, exclaiming that “he’s never done that before” (a remark I always receive with a pained expression – the implication being that animals reserve these once-in-a-lifetime stunts exclusively for me). I had no choice but to get back into the saddle because, as I said, I was miles from home.

When I tottered back into our yard later I saw five concerned faces. My head and neck hurt. I fell into bed. When Charlotte’s husband came to the door an hour later to see if I was okay I was apparently talking more gibberish than normal. I assume I had sustained some injury, because the fall wiped out my short-term memory for two days.

Returning home and finding me crocked, my husband decided instantly that I had set myself up for the fall in order to become a “competing centre of attention” with Charlotte’s daughter, who is in Taunton hospital with multiple injuries after her horse fell on top of her while she was out hunting with the Devon and Somerset staghounds.

I accepted this slight serenely, as I – temporarily only – became a much nicer person after the fall. Even my husband noticed.

“Even though I preferred you much more concussed,” he said firmly as I struggled on nobly despite a stiff neck, “I forbid you to ride again.”

And I think, for once, I might obey him.

rachel.johnson@sunday-times.co.uk

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