When she fell pregnant for the first time, she was working on multi-million-pound accounts and was required to return to full-time work after just three months. “So I quit,” she says. “I wanted to see the kids grow up.”

The website came about following a chat with another mother who had run a fashion floor at Selfridges and had told her wistfully that it was no place for a mum with babies. “I thought there must be a huge workforce of brilliant women who have chosen to be at home, but who can’t hack Bob the Builder 24/7,” says Bellamy. “Things had to be more flexible for them.” Then comes the aside: “It’s all right, darling, mummy’s coming.”

For many employers, maternity is a dirty word. Each year, 30,000 pregnant women are sacked illegally. The situation isn’t helped by the fact that, in high-powered professions, part-time working has about as much credibility as shelf-stacking. As one employer puts it: “It’s full-time or f*** off.” The result is that mothers typically return to the workforce punching below their weight in the 5C jobs — catering, cleaning, caring, cashier and clerical work.

It is, as the recent Women and Work Commission (set up to reduce the 13% wage gap between men and women) pointed out, an outrageous waste of talent.

Which is why the “because I’m worth it” generation is taking matters into its own hands. Like Bellamy, Gillian Nissim, an former communications exec and mother of two, noticed the brain drain of professional women from the workplace and decided to do something about it. Last month, she launched www.workingmums.co.uk, a database of challenging yet, crucially, flexible jobs for mums. “I’ve always employed working mums,” says Nissim. “I find them more focused, they have a greater sense of what’s important, and they have more to prove — that they can be a mother and be good at their job. And they rarely have hangovers.” On her site are former board directors, advertising planners and marketing professionals, and jobs that pay up to £300 per day.

Attitudes to working mothers are slowly changing. First Direct, Ikea, Nationwide, the BBC and Vodafone all variously lay on mum-to-be mentors, family days out, preferential nursery rates and flexible working packages. At the investment bank Lehman Brothers, working mums are the latest business drive, not least because it makes financial sense — it is estimated that increasing women’s employment would boost the economy by up to £23 billion per year. In January, the firm launched the Centre for Women in Business, a £1.75m joint venture with the London Business School, aimed at keeping women in the workplace. The first of its monthly family workshops — a talk on parenting — was held in February and hosted by the childcare guru Tanya Byron. Also in place are “parenting pals”, or maternity mentors, and a networking forum for women. The results are encouraging: in 2003, there were 43 people on flexible working packages in the company; now there are 480.

“All the research shows that the retention of women is more productive,” says Fleur Bothwick, Lehman’s European director of diversity and inclusion. “There’s added value in mothers. They’re uber-organised, and more balanced from having a life outside work.” Some, though, think that positive discrimination has gone too far. “We found that the most resentful group was single women without children,” says Bothwick.

There’s another important quality that comes with motherhood, one most employers keep to themselves. “Working mothers often have less ambition and ego than men, and that can be a positive thing,” says Simon Franks, CEO of Redbus, a media private equity group. “Of course these women could do higher-powered jobs, but a lot of the time they don’t want them. I’d love to employ two women in a job share of a senior role — say a financial controller. A guy in that job would just want to be promoted to financial director. As it happens, I couldn’t find anyone to job-share, but professional part-time mothers are good for society because we want women to have kids. It’s good for me, because it makes economic sense, and good for them, because they get a great job that they don’t have to take home with them. I think many women are surprised at how much they love bringing up kids.”

It’s still early days for a more mother-friendly working environment. Many companies flout the legislation, the pay gap is even bigger in part-time work, and discrimination against returning mothers is rife. But the revolution has definitely started — even if it’s still in nappies.

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