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Look around and the signs are there. Most of us know of women in their mid-30s who haven't had children. But research published last week showed a startling picture - 40 per cent of graduate women in Britain are still childless by the age of 35, an increase
of 20 per cent in just over 10 years. A third of female university graduates will never have children.
Some right-wing commentators blamed these "selfish" women for the nation's pensions crisis. Others asked, "Who is to blame?" But the author of the research - like women all over Britain - says the real questions are much more complex.
The findings come from a study of more than 5000 women born in 1970 and tracked throughout their lives by researchers at the Centre for Longitudinal Studies, at the University of London.
"Highly educated women are more likely not to have children young and they are more likely to end up with none," says research team head Professor Heather Joshi.
"It's probably because they have better paying careers, better alternatives. They may have the kind of careers in which they need to settle before they think about having breaks or finding the means to combine parenthood with paid work. They may have higher aspirations about housing and who they will settle with. There are a lot of factors."
Author Lionel Shriver, 49, chose not to become a mother. "For me, establishing myself as a writer was so important, and took so long, that it consumed my entire reproductive lifetime ... I didn't feel I could afford the distraction and emotional energy that it would have taken to try and raise a family at the same time."
Shriver, who won the Orange Prize in 2005, believes that had she become more successful earlier in her career, she would have been more likely to have had children. But she is at peace with her decision.
"I think that's because I've never had the experience and so I don't know what I'm missing. There is an element of ignorance being bliss. It does mean that in terms of my emotional support system, it's rather narrow. If anything happens to my husband, who is older than I am and smokes, I'm really by myself. So the chances are very good that I end up living the last 20 years by myself."
Others are more concerned about Britain's low birth rate. Tory education spokesman David Willetts is one who suspects that not everyone is as content with their childlessness as is Shriver.
"I think high house prices are a very powerful contraceptive," he says. "I think one thing that's going wrong with our country is negotiating the stages of the cycle of a life course. Leaving the parental home to create a new parental home, which a generation ago happened without thinking for many young people, has become much harder.
"There is a great issue of the increasing debts that young people have after university and the huge increase in the cost of housing. Are the young going to be able to have the kids they wish to have, buy the family house they want to buy and build the pension savings that they need? We're failing them on all those measures."
Many woman point out that a principal reason for not having children, often overlooked by academics, policy wonks and politicians, is that they do not find someone they want to settle down with.
One in three women is still single at 35. Women no longer need to marry for economic reasons or social standing, and they are finding that the men they meet don't live up to their expectations.
Kathy Cluney, 43, a single psychologist who would have had children in the right relationship, says: "A man recently said to me that he couldn't understand why I hadn't been snapped up. You're not waiting to be snapped up, you're looking for a match that will be as good for you as it is for them ... that will sustain you mentally and emotionally."
It is not too much to ask. But Shriver, whose new novel, The Post-Birthday World, explores the subject, warns that every partner has limitations.
"When you are considering getting married you don't want to resign yourself to something that's short of the mark, but everybody is. I think that if you keep your expectations modest and introduce a measure of kindness, you have a better chance of finding enduring love."
It is not always lack of money, or lack of a man that prevents women having children. Some say they simply lack the maternal instinct.
Actress Dame Helen Mirren, 61, said: "It's just not something that interests me. An awful lot of women don't want children, but have them because there is such pressure to do so. They think there's something wrong with them if they don't want kids. It's not right."
Natalie Haynes, 32, a comedian from London, is another.
"I didn't touch a baby until I was 30 and still haven't held one. I've no idea why anyone would want children. I don't hate them. It just seems irrelevant. My partner doesn't want one either so it all worked out fine. Most of my friends don't have them. I served a very long apprenticeship as a stand-up. Had I wanted one I would have had to have given up my career.
"You can't afford a place for two people in the southeast, let alone with children. It's plausible that even if you are going to be really successful, it won't be until you're in your mid-30s or 40s. Sadly, that's too late. For a lot of people not having children is about not being at the right age, with the right fertility and the right pay cheque."
Some women are put off motherhood by the fact that they will not only have to put in a day's work at the office, but will then have to do the lion's share of the domestic chores.
"I would have liked to have been a mother, but I couldn't think of being one without the support of a man, and yet the notion of what I might have become didn't appeal to me," says Kathy Cluney. "I don't think family life is a great thing for a woman. From my own family experience, family was a great institution for men, but not women."
And it isn't necessarily the woman who wants to continue working. Many want to stay at home with their children, but their partner doesn't want to be the sole breadwinner. And some men don't want children, or continually put it off.
Beth Follini, a life coach who specialises in coaching women who cannot decide whether to have children, says: "Some of my clients are in relationships with 35-year-old men who think that they are too young to become fathers. In all the debates about why women aren't having children, this is the great unspoken problem. Where are the men? Having children challenges their view of themselves as eternal adolescents."
For some, the eventual regret of not having been a mother will be deeply felt. Tracey Emin has contemplated the future that lies ahead of her without children. "Sometimes I imagine I'll be an old lady surrounded by all my newspaper clippings," she once said.
Emilie Pagan, 38, a successful businesswoman, chose her career over a baby. Five years into a good relationship her boyfriend asked her to have children and slow down on the job.
"I was about 32 at the time and agonised over it for ages," she says. "I always worked late socialising with clients, which was really important for the job. Incredibly stupidly, with hindsight, I chose the job and now totally regret it.
"I'll probably never have kids. He went off and married someone else. I'm going out with someone now, but he never wants to have children. When I could have children, I thought that I couldn't jeopardise my career. Now I think what an idiot I was."
Childlessness in New Zealand
* Childless couples now make up 40 per cent of all New Zealand families, last year's Census shows.
* The figure includes couples who have never had children and those whose children have left home.
* A total of 461,217 or 28 per cent of women had no children.
- INDEPENDENT
