THERE was a stoush last week between former The Age editor Andrew Jaspan and powerful advertising buyer Harold Mitchell over whether Jaspan had said that the job of editing a newspaper was "too tough" for women. Jaspan didn't exactly say that. Trying to explain why there are so few female newspaper editors he had said: "I think particularly when it comes to newspapers these are incredibly demanding jobs, they are not family friendly. They are terribly destructive jobs." Instead of criticising Jaspan, Mitchell should have praised him for speaking the truth. Traditional daily newspapers, with their 10 pm deadlines and all-consuming demands, are particularly lethal for family life unless there is a selfless full-time spouse at home. By the time most women are in the running for the top job they are in their 30s, with the biological clock ticking. For increasing numbers in recent years, the pragmatic choice is to step away if they want children. That is the main reason why few women are CEOs. Not because they aren't educated, talented, or driven enough. Not altogether because the boys' club sabotages them. But because they have made a choice informed by their maternal instincts. For every Gail Kelly with triplets or Julia Gillard without children, there are countless equally able women who made the decision to scale back. The fact they feel good about taking the Mummy track is a tribute to the evolution of a new feminism over the past 15 years, in which all choices are valid, workplaces more flexible and maternity leave a serious part of the political agenda. A generation of women who had grown up watching their mothers struggle to be superwoman knew the cost of trying to "have it all". Learning from the mistakes of their feminist forebears, they were free to make the choice that suits them best. Or at least that used to be the case. But superwoman, it seems, was never dead, only resting. Hello Marissa Mayer. Yahoo's 37-year-old new chief executive announced last week she was six months pregnant, hours after she was revealed as the struggling internet company's boss. As the world's first pregnant Fortune 500 CEO, the computer engineer is a trailblazer, but I believe her declaration that she will take only two or three weeks' maternity leave sends the wrong message to a generation which was starting to learn from the mistakes of the past. "I like to stay in the rhythm of things," Mayer told Fortune magazine. "My maternity leave will be a few weeks long and I'll work throughout it." It's her choice, but as a successful female executive in a geek world, she is already a celebrity role model. Her choice has an impact on every woman behind her, which is why everyone has an opinion on her maternity leave or lack of it. She has raised the bar for working women everywhere but I fear has also sent us back to the 1970s. She makes the woman wanting six months off to breastfeed and bond with her baby look like a self-indulgent lightweight. Having a baby becomes a macho activity to some, no more distracting than running a marathon, with the resulting child to be outsourced like any other household chore. Since Mayer is renowned as a perfectionist detail freak about all other aspects of her life, it's hard to know why she would be comfortable short-changing what is surely her most important endeavour. She can afford nannies. She lives in a penthouse of San Francisco's Four Seasons Hotel, where pesky chores are taken care of. Her husband Zachary Bogue, a venture capitalist, may have a more flexible schedule that allows time for their child, though he hasn't commented. No one doubts Mayer's work ethic. At Google she worked such long hours she often ended up sleeping at her desk. But for Mayer to turn Yahoo around where four previous CEOs in four years have failed will require a herculean effort. I fear that can only be achieved by sacrificing time with her baby, time that every instinct of mother and child will ache for, an intense physical ache that no first-time expectant mother is prepared for. The sad fact is that women can no longer tell the truth of their own experience as working mothers without being howled down for betraying the female cause. Now the idea appears to be to lull women into thinking that "having it all" is a breeze because by the time they discover it isn't they will have forged a little further through the glass ceiling. They are the female equivalent of cannon fodder going over the top in the trenches of Gallipoli. Every blood-soaked inch of territory is worth it, according to the armchair generals of feminism. "You can't write that," US foreign policy analyst Anne-Marie Slaughter, 53, was told when she decided to write a column titled: "Why women can't have it all." The hotly discussed piece , in this month's Atlantic magazine, explained that she pulled out of her "dream job" working for Hillary Clinton because her children were suffering from her absence, even though she had a supportive husband. In its first week it was read online by almost a million people around the world and became the magazine's most "liked" piece ever on Facebook.What Slaughter and so many other career women with children know is that a baby is not a part-time, short-term accessory. If anything it needs more attention the older it gets. Mothers of teens often talk about being blindsided by the needs of seemingly self-sufficient quasi adults. Slaughter's epiphany came when her 14-year-old son started getting into trouble at school. "Over the summer, we had barely spoken to each other." I've been speaking to groups of girls and young women since about 2000 when I first started writing about the fertility hoax, as doctors started warning that science can't beat the biological clock. Over time I noticed a shift in the attitudes of these young women; they began to take children into account much earlier when planning a career. By 2003 The New York Times Magazine published "The Opt-Out Revolution", the hot button issue of high-powered, highly educated, women who had put their careers aside to stay home and raise their children working part-time if at all. We went from "superwoman" to "domestic goddess" in a flash, but central was a desire to put the welfare of the child first. So no matter how much we applaud and admire Mayer, it's not to see her decision as a retrograde step.