Naomi Wolf wants to talk to us, openly and frankly, about her vagina. She wants to tell us about the post-medical-crisis epiphany she had, which led to a "thought provoking, revelatory experience that suggested a possibly crucial relationship of the vagina to female consciousness itself." She wants to inform us about the "scores of men...who responded to my questions about their relationship with the vagina with hearteningly endearing answers." She wants to make us all jealous of her amazing vaginal orgasms, which allow her to "experience the sense of heightened interconnectedness, which the Romantic poets and painters called the Sublime" and "hint of a sense of all things shivering with light" (lucky cow). And most of all, she wants to share her great insights with the women of the world: she wants to teach them the secrets of the "Goddess array", a set of head-stroking, armpit-sniffing, pulse-quickening behaviours that will allow us to experience the kind of earth-moving shags that Naomi seems to have on a daily basis.

These may all seem like noble, laudable aims - all presented by someone we're told is one of the most eminent voices of the third wave feminist movement. It's a shame then that Vagina reads like a 355-page nervous breakdown.

In Vagina, Wolf posits a sense of sexual fulfilment ruled by heterosexual desire and a keen sense of monogamy, all wrapped up in some seriously dubious pseudoscience: according to her, a woman's brain and her vagina are inextricably linked together and our creative potential can only be unleashed via penetration by a strong virile man (pity all those poor single women, their potential remaining untapped as they comfort themselves with their vibrators and pints of Haagen Daas). Women are presented as ridiculous, simplistic creatures whose fannies act as neural divining rods, constantly seeking out and defining ourselves by the amount of male attention we receive and falling into a deep depression when none is forthcoming.

In Wolf's world, we are very much "the fairer sex", a bunch of swooning hothouse flowers who like nothing more than burying our faces into our lover's sweaty shirts so we can bathe ourselves in their awe-inspiring masculinity. A curt word or unthinking action from an unfeeling male can cut us to the quick and cause irrevocable damage to our magic vaginas: damage that can only be healed by a trip to a "yoni massager," a shamanic individual who can heal our battered egos by palpating our pubises, sweet-talking our inner goddesses and even entering our "sacred spots" for the low, low price of £150 an hour.

Floating above this all is Naomi herself – a weirdly schizophrenic persona. One the one hand, she's all 70s Earth Mother schtick, so in touch with her inner goddess that it's surprising she's not formed her own Church of the Holy Punani. On the other, there's a fragile, consumptive Victorian heroine, ready to take to her bedchamber at the mere mention of minge. Take, for example, the now infamous section of the book where she discusses the pasta party she attended where guests made "cuntini", which was to be accompanied by "several dozen enormous sausages" and "several immense salmon fillets". Wolf was so affected by this show of culinary cuntdom that she "could not type another word of the book - not even research notes - for six months." Why? "I felt on both a creative and a physical level that I had been punished for going somewhere that women are not supposed to go."

Wolf's work has always been contradictory. A supposed third-wave feminist who is gender essentialist and anti-porn; she's pro-choice yet thinks abortion is murder. The author of The Beauty Myth (a book she has dined out on for 20 years) who took a job giving Bill Clinton fashion advice and an intellectual heavyweight who allegedly files copy to newspapers in ALL CAPS. For a self-described liberal writer, there is a nasty streak of sexual conservatism running through her Vagina: while Wolf waxes lyrical about women such as Edith Wharton, Anais Nin and George Eliot, whose work was born out of sexual awakening, she is curiously silent on the subject of those women whose creativity was born out of lesbian or even celibate desires. Wolf freely admits that her writing is influenced by her own experiences of heterosexual sex, but there seems to be almost no acknowledgement of same-sex impulses expressed through non-penetrative actions. While she occasionally acknowledges the existence of women-women relationships, it's more as a kind of lip (labia?) service; a kind of "yeah, yeah, you lesbians might claim to have great sex, but you don't know what you're missing."

Take, for example, a quote from a conversation she has with a fellow attendee of a "yoni massage workshop":

"'Do you feel your emergent sexuality equals emergent aspects of yourself?’ I asked. 'Yes,’ she replied. Then she added, 'Some wounds women have can only be healed by man.’"

If you're wondering what the sound you can hear after reading that little snippet is, it's Andrea Dworkin turning so hard in her grave that she's almost tunnelled her way to Tartarus.

In fact, Dworkin – like most feminist theorists – barely gets a look-in in Wolf’s Vagina. Sure, there's the odd bit of fashionable neurobollocks (just-so stories told via pictures of brains with blobs of colour on them), but this book, like pretty much all of Wolf's work to date, consists largely of personal views and anecdote rather than anything grounded in theory. Remember, it's Naomi Wolf's Vagina. Not mine. Not yours.

When you're not laughing at Vagina (and I'd like to apologise to the passengers of the train I was on for mumbling "You can fuck off if you think I'm calling my fanny a 'Jade Gate', love" slightly louder than I really should have in public) you find yourself feeling incredibly depressed by it. Here is an eminent self-styled feminist suggesting that women are defined and governed by the bits of flesh between their legs (and, perhaps more irreconcilably, the bits of flesh between men's legs). If we are unlucky enough to ever be raped, we become "damaged goods", as our vaginas will seize up from the trauma (an argument worryingly similar to that made by US Republican senator Todd Akin, who recently stated that women's bodies "shut down" during "legitimate rapes"). This is feminism for the 50 Shades of Grey crowd - a belief that all a girl needs for a lifetime of fulfilment is the love of a good, emotionally domineering, sexually aggressive man – that, and the odd yoni massage. Is it cynical to suspect that Wolf is peddling this heteronormative guff, knowing full well that the patriarchy she used to rail against will lap it up, as an example of someone with capital-F feminist bona fides confirming their own prejudices?

At the beginning of Vagina, Wolf states that "the vagina may be a 'hole' but it is, properly understood, a Goddess-shaped one." I suggest that, if she ever wants to be taken seriously again, Wolf pulls her head out of her "Goddess-shaped" hole and starts living in the real world.

Vagina is available now on Virago