Latest figures by the Journal of The American Medical Association report that up to 76 per cent of women are likely to experience sexual dysfunction at some stage in their lives, but according to Drs Laura and Jennifer Berman, the problem is international, and far more common than we think.

'Women with sex problems are usually given the brush off by doctors. Any interest usually revolves around pain, or if she is able to have sex at all. The idea of a woman's right to sexual enjoyment is taboo. There's been a reluctance to accept that it's not all in our heads. It's not socially or medically accepted,' says older sister, Dr Jennifer Berman, 36.

Based on their work as co-directors of the Women's Sexual Centre in Boston, Dr Berman and her sister, psychologist Dr Laura Berman, have produced a book combining a psychological and physical approach to sexual dysfunction.

The clinic was the realisation of a long-time dream for the sisters, who had previously swapped notes on their research in this field. Jennifer, as a surgeon and urologist was concerned about the sexual desensitisation women suffered after pelvic surgery and was alarmed at the lack of medical information on female nerve structures that run from the uterus, the clitoris and vagina. 'Surgeons have been operating on men using microscopes to spare sexual function, but none can tell me where similar nerve structures are in women,' she says.

Laura, 32, has always been interested in women's sexual health and believes that sexual power and personal power are inextricably linked. 'That sense of sexual entitlement empowers a woman in all areas of her life and balances her,' she says. 'We have made great advances in the work-place, in family life and financially, but the majority of women are not satisfied sexually. When women feel entitled to sexual fulfilment that's when we'll see a woman in the White House. Sex is the way forward.'

If sex is the last frontier to women's equality, then what does this mean for men? 'Women say, "I make more money than him so if I start instructing him in the bedroom, he's going to run screaming and I'll be left all alone. I don't want that,"' notes Laura. But Jennifer reassures. 'Most of our patients' male partners are always responsive to their partner's difficulties. Often they are relieved that it is all out in the open and that the woman is being honest. The process empowers them, too.'

Until now, the main solution to sexual dysfunction has been faking it. But according to the Bermans, that has to stop. 'Don't start it, and if you are doing it, stop,' Jennifer advises. 'It's hard if it's been going on for years and you suddenly stop. Be prepared for your relationship to go into crisis because your partner will feel it like a betrayal, and will wonder what else you have been lying about. It becomes a very big issue and you have to make sure you have support.'

Both women are keen to point out that although orgasm is correlated with sexual satisfaction, many women are satisfied by the intimacy of sex without climax. 'We don't advocate that sex should be goal oriented,' Laura says. 'It only causes distress if it becomes an issue that deserves treatment.'

And this is the main message of For Women Only; that sexual dysfunction is treatable, both medically and therapeutically. Thanks to the Berman sisters, the medical fraternity might be getting that message, too.

Common causes of sexual dysfunction:

'Why does the field of women's sexual health lag 30 years behind that of men? Why haven't women received the same attention? To understand the present we have to consider the past,,,' The Bermans on the history of female sexuality - read on.