Last Saturday, Alison Marshall spent most of the day at a soft-play centre with Lily, 4, and Jack, 3. She watched over them lovingly as they rushed around like lunatics, comforted them when they fell off the climbing frames, and fed them healthy snacks from the café. To the other parents there she would have looked like any other mum with her children. But, at the end of the day, Alison dropped off her niece and nephew at her sister’s house and returned home to her husband, and her peaceful, child-free home.

“I love Lily and Jack, really enjoy spending time with them, but I’m aware that that’s because at the end of the day I can give them back,” says Marshall, 42. “I’ve never felt the urge to have my own children, but I’ve always enjoyed spending time with other people’s. Kids are great but, for me, only in small doses.”

Marshall and her husband are an example of the new childless couple. Redefined as “childfree”, these are not the tragically-unable-to-conceive; they are contented women and men who have opted not to become parents. Their numbers are growing, says the Office of National Statistics. One woman in five now remains childless, with nearly one degree-educated woman in three never becoming a mother. In the US, according to a census in 2003, 42 per cent of women don’t have children.

The question that perplexes many people is why. The obvious answer, one that upsets the child-free, is selfishness: children are demanding and require attention 24/7. This appears to be the view of the Catholic Church. Last month, the Pope said that Europe no longer seemed to want to have children and blamed “the wish to have one’s whole life to one’s self” for people choosing to be childless.

Selfish or not, most women who have opted to remain child-free lead happy, fulfilled lives, claims Nicki Defago, 39, a freelance TV producer, the author of Childfree and Loving It (Vision, £10.99) and one of the champions of the childless life. “I always assumed I’d have kids but, as soon as I was married and settled, the brakes went on in my head,” she says. “I like having my own space and I spend a couple of months each year travelling. And then there’s my work and relationships. The only disadvantage to being child-free is that people never stop asking why you don’t have them. When you explain it’s simply because you just didn’t want kids, people can become hostile.”

Many people mistakenly assume she is a child-hater. “The idea that those who opt not to have a family are child-haters is wrong,” says Dr Gail Kinman, a psychologist at Luton University who has researched this area. “They often tend to play caring roles; they may be very active aunts or godparents, or be involved in care of the elderly. It can often be people who have spent a lot of time with other people’s children who opt out of having their own.”

Parenthood is not necessarily natural, she adds. “The so-called maternal instinct is likely to be learnt rather than biological, so if your childhood wasn’t particularly happy you may not have those feelings. For some women, parenthood is associated with negative things, disruption, poverty and a lower quality of life.”

For those women who don’t feel a biological urge to reproduce, the fourth decade can be deeply troubling. “I spent most of my thirties in a complete ‘browclutch’; should I or shouldn’t I have kids,” says Serena Jennings, 41, who has been married for 15 years. “I worried that if I didn’t have them I’d regret it, but I felt that if I did our lives would change in a way I simply didn’t want. My husband Chris (45) and I have always shared everything and I knew that having children would change the balance of our relationship. I didn’t want that to happen.”

Ironically, the equality that feminism has brought to relationships, with both partners working, sharing financial and domestic responsibilities, can become a problem when children are on the horizon, as women realise that their role within the partnership will change. The struggle against this change has created the concept of “having it all”, career, children and a contented relationship, which exhausts many women. “But younger women are starting to question this concept,” says Dr Angela Carter, a psychologist at the University of Sheffield. “They are realising that it’s not necessarily the most rewarding thing to strive for. Women in their twenties no longer see having children as the ultimate in fulfilment. Instead of wanting a career and a family, they are starting to opt for one or the other. There is a slow realisation that some women will be happier if they remain child-free.”

The same, perhaps less surprisingly, is true of many men. “I would never have said to my wife that we couldn’t have kids,” says Chris Jennings, “but I have to admit to being relieved when Serena decided not to. The thought of having that responsibility makes me claustrophobic, I would hate the restrictions that children bring.”

Jennings believes that his relationship with Serena is stronger for not having children. “I know people often look at couples without children and think they must be empty, but I think our lives are fuller because of it,” he says. “We have a huge group of friends — with and without kids — that we can spend proper time with, and we see a lot of our families, too. We live in the country and have people staying with us almost every weekend; that’s possible because we don’t have kids to sort out.”

Even when a convincing argument is presented, many people still ask how can any woman not want children? And this can bestow a feeling of invalidity on child-free women, a sense that is increasingly creeping into the workplace. “Working mothers can now request flexible working, compressed hours or flexitime, and the company has to consider it,” says Gail Kinman. “Child-free women are not afforded the same flexibility and this is starting to cause real resentment.”

The different treatment of mothers and child-free women is creating a serious divide; many women feel they are not treated seriously in the workplace when they return after maternity leave, while women without children can feel penalised for their choice.

Ironically, it is often women who exacerbate this divide, causing both sides to take up exaggerated positions that inflame the situation further. “When friends of mine with kids come round, I sometimes feel they are like pyramid sellers trying to recruit me to the cause, planting their babies in my arms, telling me how fulfilled they are,” says Alison Marshall. “I can’t help but feel that some of my friends with kids perceive my life as superficial or even a bit sad.

‘Who will look after you when you’re old?’ I’m asked repeatedly, but why is that a valid reason to have kids?” It’s a question that is often asked, both by those with children and those trying to decide whether to have them, but there is no evidence that women with children are looked after any better in old age. “People think children will be there to care for them when they are older, but that’s not always the case,” says Dr Carter, “and kids are no guarantee against loneliness. All the surveys show that the most important factor in a contented old age is good friendships, and often it’s women without children who have had the time to maintain close relationships.”

But whether or not they are lonely, will old age be filled with regret over the children they never had? “It depends on circumstance,” says Kinman. “If you remained child-free because you weren’t sure, left it too late and then couldn’t have kids, or because your partner didn’t want a family, then you may go through a period of mourning when the menopause hits and children are no longer an option. But if you genuinely didn’t want a family, and are living a happy and fulfilled life, what is there to regret?”

Minding the gap?

• The biggest risk for child-free women is cancer; The risk of developing breast cancer increases by 3% for each year that a woman delays having children (although this is the same as for women who opt to have their first child after the age of 30).
  
  
  
  
• Women who had children later in life (over 35) have a 58 per cent less chance of developing ovarian cancer than child-free women, according to the Association for International Cancer Research (AICR)
  
  
• But you will save a lot of dosh. At the last estimate, raising a child costs an eye-watering £180,137, until the age of 21.
  
  
  
  
• A study in the Journal of Marriage and Family found that among child-free couples, the man was more inclined to feel broody than the woman.
  
  
  
  
• In a 2003 survey of 1,500 parents, about one woman in three and one man in 20, admitted that kids had not made them happier.
  
  
  
  
• Research in 2004 revealed that most childless women are in middle and lower-level jobs, rather than being high-fliers and career-driven.

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