Who said oranges were the only fruit?

One apple tasted by Josa Young

And here she speaks to The Telegraph just after publication

I couldn't write about sex at all until after my mother died. Growing up in the 1970s, the official parental line was that nice girls didn't, you know, do it, let alone write about it – although it was a different story for my brothers. Double standards were the order of the day.

Which meant, in effect, that I was barred from writing fiction. In order to create fully rounded human beings, and describe their relationships with each other, I would have to tackle the subject of sex – along with intimacy, misguided love, death, resentment, friendship, the passion of women for their babies, the problems of marriage and finding the right person, and all the rest of the complicated, messy stuff that humans do. When a parent dies, there is grief, of course, but there is also liberation. You must grow up, and one of the grown-up things I wanted to do was write novels.

When I put a sample chapter of my debut novel One Apple Tasted online, a friend advised me to take it down. Too raunchy, she said. Yes, it had rude words in it, but I thought it was a rather mild scene of two people with wildly different agendas ending up not doing it at all. Because that is part of most people's sexual experience – deeply unsatisfactory, particularly when young, and when you don't really know the other person.

Yesterday, a survey about the reading habits of 2,000 women aged between 45 and 60 reveals that nearly two thirds are keen on raunchy scenes in novels. Add a decade or two, and you've got an even broader readership: my parents-in-law – far more liberated than my own parents – said they loved the book. In fact my mother-in-law praised my ability to write realistically about sex – rather surprising, perhaps, for a "nice girl".

After my parents had both died (when I was 47), I found passionate letters and photographs dating from the Second World War that told a very different story about their attitudes when young. Perhaps I sensed the undertow that informed their marriage, and writing about earlier generations has been my way of trying to work it out.

The prim and proper 1950s seemed to reset the sexual clock back to Edwardian double standards, and wartime liberality in the face of imminent death was quickly shuffled back under the carpet. Now I wish my mother had been alive to see my book published, as I realise she would not have been shocked at all.

Far worse than hypocrisy to me is the sterile Noughties take on sex – that it has the same emotional weight as a game of tennis, with orgasm rather than straight sets as the goal. I sometimes try to work out what market force is driving this sickly dumbing down of Eros, this bossy and unattractive blunting of his exquisitely painful arrow with a nubbly rubber sucker.

Sex is sold to the young as a supposedly consequence-free activity in a thousand flavours and textures, but free from the wild, driving emotional life force that gives it meaning. What about intimacy? What about the human life that may (or may not) begin? What about a thousand ships? What about crimes of passion (still with us)? No one kills each other or chases each other across the globe for a game of tennis.

The floodgates opened, and out of me poured, in the space of five weeks, the first draft of One Apple Tasted. I wrote it in a freezing, semi-abandoned building in Bayswater, wrapped in a blanket with mittens on my hands. I was amazed by what my characters got up to – quite unexpected goings-on in the front seats of cars, in punts – anywhere really. In the 1950s and the 1980s, among other decades. But there were reasons for their behaviour, deeply rooted in who they were and how they thought and the mores of the time in which the scenes are set. The love-making was significant both to character and plot: my characters took their clothes off all right – but only if the role demanded it. I didn't just drop in historically accurate 1950s heavy-petting scenes to keep me warm as the chill February wind blew through the broken window.

I took a deep breath and just went for it, typing up to 8,000 words a day. Drawing on what I knew as a grown-up woman about what people do – and don't do – when trying to get it on with another person. Sex in films and in books is often so completely unrealistic and unmoving that for years I thought I must be doing it wrong. Writing about it is a terrific risk. What if I am wrong about it too? Not "good in bed", not able to write realistic scenes. When Auberon Waugh set up the Bad Sex in Fiction award in 1993 for purple passages by the likes of Tom Wolfe, Norman Mailer and Melvyn Bragg, the aim was "to draw attention to the crude, tasteless, often perfunctory use of redundant passages of sexual description in the modern novel, and to discourage it." Even now as I write this, I wonder what people will think.

In the run up to publication, I read quite a few "hen lit" and "chick lit" novels to see what they were like. I was quite astonished to see how old-fashioned some were, with women taking quite traditional roles and doing polite and rather unrealistic jobs. There were sex scenes all right, but they seemed dropped in from a great height, and quite pornographic while lacking authenticity and passion. The men tend to be flawless, romantic heroes with rippling muscles that do not, in real life, exist on men who also have a good sense of humour – one of the sexiest attributes a man can have.

My hero is beautiful, certainly (at least to begin with), and funny, but he is deeply flawed. Spoilt and indulged, he has no idea of what women are thinking or feeling and is as hormone-driven and indiscriminate as young men I knew. But I had to check with my husband that his thought processes were authentic.

One major aspect of sexuality that is much ignored in the modern novel is not doing it. And virginity is another theme of One Apple Tasted – where you hang on to it for so long that it becomes hideously significant and hard to shed. In a time when we are meant to have sex all day, every day, drawing on tips from magazines and newspapers to "spice things up in the bedroom", virginity, chastity and celibacy seem thoroughly controversial life choices. But they are part of people's sexual experience, and just as valid as the more exotic perversions that get a regular airing in the tabloids.

For women of my generation, growing up in rapidly changing times, reading about the authentic experience of others of this most intimate part of our lives should be comforting, exciting and moving. It grounds us and makes us feel normal. If it makes us feel sexy as well, then that is all to the good.

I am in the business of reminding my readers that it doesn't matter much what age you are, or whether you have a perfect body, but that love and life and sex are – or should be – intimately entwined. That sex really matters and is nothing to be ashamed of. That the best sex comes from long and loving relationships, and genuine intimacy is the goal for which we should strive, whatever our age. I have no objections at all to good sex scenes, it is Bad Sex that makes me cross and bored and embarrassed – in books as well as in real life.

One Apple Tasted by Josa Young (E&T Books)