I know some men claim to be able to put their finger, so to speak, on a woman's G-spot and give her boundless sexual pleasure. Researchers have had less luck, mocked by feminists and experts whenever they claim to have identified this elusive part of the female anatomy. But few have gone so far as a retired professor of gynaecology who says he's finally found physical proof of its existence – on a corpse.

Now it's possible that you have already, like me, spotted the flaw in Dr Adam Ostrzenski's experiment. Most research on the G-spot has involved live women who could, presumably, shout "Yes, yes, yes!" if the study turned out to be successful. In fact, most research tends towards the proposition that the existence of the G-spot is a myth or at best unproven, which is what Dr Amichai Kilchevsky of the Yale-New Haven Hospital in Connecticut concluded after reviewing 100 studies.

The G-spot gets its name from Dr Ernst Grafenberg, the German gynaecologist who claimed to have discovered it in the middle of the last century. It's always seemed to me a weird obsession, very well summed up by Dr Leonore Tiefer, of New York University, who compares the quest for the G-spot to searching for the Holy Grail with a divining rod: "'I've got it', 'No, over here', 'No, over there', 'Darn it, well, keep looking'."

Now Ostrzenski is claiming to have found anatomical evidence for the first time in the form of a tiny sac – 8.1mm long, 3.6mm at its widest and with a height of 0.4mm – on the back wall of a woman's vagina. He discovered it after dissecting the genitalia of an 83-year-old Polish woman at Warsaw Medical University, 24 hours after she had died from a blow to the head.

You might think it's tasteless to carry out this research on a murder victim, who couldn't give or withhold consent for obvious reasons. But it's also rather pointless, given that she couldn't answer questions about her sexual or medical history. No one knows the relation of this structure (apparently it resembled a grape) to her actual experience, and they certainly can't ask her about it.

But the truly weird thing about these periodic bouts of excitement about the G-spot is that we already know that women have an organ of sexual pleasure. It's called the clitoris and no one doubts what it's there for, so why this recurrent search for something else? Something, moreover, that just happens to be conveniently located for the form of sexual activity that gives pleasure to most heterosexual men. I don't think you have to be a genius, or indeed medically qualified, to come up with the answer.

We have Sigmund Freud to blame for much of this. The feminist Anne Koedt called him "a father of the vaginal orgasm" because of his rather sniffy insistence that it was the centre of pleasure for "mature" women. Koedt drew on the work of mid-20th-century sex researchers, principally Kinsey and Masters & Johnson, who transformed ideas about female pleasure by showing that the vagina didn't have sufficient nerve endings to experience the sensations attributed to it. Koedt's essay went a step further, arguing that the vaginal orgasm was a myth and liberating millions of healthy women from the fear of being judged frigid. Forty-two years later, the essay is still a popular read on feminist websites.

It's no accident, I think, that someone discovered the G-spot just at the moment when traditional ideas about how women reach orgasm were being overturned; it's a more woman-friendly way of saying the same old thing about the primacy of sexual intercourse for both sexes. But Koedt pointed out something else which is relevant to the recurrent cultural fascination with the G-spot. She argued persuasively that fear of the clitoris was widespread, leading to attempts to deny its importance in the West, and the horrific practice of cutting it out in the Middle East.

This sinister practice is still going on. Earlier this week, the Egyptian-American feminist Mona Eltahaway caused a storm with an essay in Foreign Policy magazine about misogyny in the Middle East, entitled "Why do they hate us?" Eltahaway was beaten up and sexually assaulted by police in Cairo last year and her article lists a "litany of abuses" against women in Arab countries. One of those abuses is female genital mutilation (FGM) and Eltahawy points out that "more than 90 per cent of ever-married women in Egypt – including my mother and all but one of her six sisters – have had their genitals cut in the name of modesty".

FGM is illegal in Egypt but it's still carried out on thousands of pre-pubescent girls. In this country, girls from East African families are at risk of undergoing it illicitly or being sent abroad for the procedure, which causes permanent damage to sexual health. And if it seems a stretch to talk about FGM and the G-spot in the same breath, maybe that's because we still haven't acknowledged the power of female pleasure – or the fear it evokes. Forget the G-spot and penis envy. Guys, it's time to talk about the clitoris.