Samantha Jenner was a true corporate high-flyer; by the age of 36 she was a senior manager at a blue-chip organisation with international clients, a 300-strong team working under her and glittering career prospects.

When she announced she was pregnant with her first child four years ago there were celebrations all round and she went off for six months’ maternity leave believing she would be fully supported on her return to her high-powered role. She was wrong.

“There had been a lot of changes within the organisation while I’d been away,” she said.

“No-one told me anything when I got back; it took me a week to realise that my responsibilities had been rearranged completely.” Jenner worked hard to reestablish her relationships with the international stakeholders she represented but found she had been stripped of her managerial responsibilities.

“My old team members were all reporting to other people,” she said. “My job didn’t seem to exist.”

Last week the conclusion of a legal battle between the Giorgio Armani group and its former employee Sarah Vince-Cain was a reminder that situations like Jenner’s are not rare. Vince-Cain won £120,000 in compensation for unfair dismissal and sex discrimination after she was pushed into a lower-level role and eventually sacked after her second maternity leave.

The news that the Giorgio Armani group had failed in its High Court appeal against the verdict came on the day that Nicola Brewer, chief executive of the Equalities and Human Rights Commission, warned that equality laws may now be holding women back at work.

“There has been a sea change on maternity leave and flexible work and we welcome that,” she said. “But the effect has been to reinforce some traditional patterns. The Work and Families Act has not freed parents and given them real choice. It is based on assumptions, and some of the terms reinforce the traditional pattern of women as the carers of children.”

Brewer said her concerns that these days women of childbearing age might be overlooked when applying for jobs had deepened after the millionaire entrepreneur Sir Alan Sugar said some employers discarded CVs from such women. “We have come a long way but after winning all these gains it is worth asking: Are we still on the right track? “I worry that current legislation and regulations have had the unintended consequence of making women a less attractive prospect to employers.”

Research by the Fawcett Society, which campaigns for equality between women and men, revealed that 30,000 women a year were losing their jobs because they were pregnant.

Anecdotal evidence also suggested that Brewer was right to feel worried. In Samantha Jenner’s case, her rapid ascent of the career ladder was undoubtedly stalled by taking six months’ maternity leave, and when she became pregnant again – during a time when her employer was in the middle of restructuring – she decided to accept a period of gardening leave and quit the company for good.

She now runs her own textiles business and consultancy. Amanda Alexander is the founder of Corporate Mothers, a maternity coaching company and HR consultancy that advises businesses on how to retain working mothers.

She said: “There are too many highly trained professional women who just drop off the career ladder. Many of the women who come to my seminars say that their careers have stagnated after they’ve gone part-time or tried working from home.”

Alexander suffered a similar fate in her previous career as a project manager in the IT sector. “I asked to work four days a week but my employer refused. Soon afterwards I was made redundant,” she said. “I’m sure the business reasons for it were sound but I did wonder if it would have been the same if I hadn’t asked to go part-time.” Even when the part-time option is available, it can mean accepting a reduced level of responsibility that can hinder chances of future promotion.

Claire Scott chose to return part-time to her job in events management when she had her first child 10 years ago. “From my own experience I would never recommend it,” she said. “You end up squeezing the work of a full-time job into fewer hours and I was always aware of the difficulties it caused my colleagues, who had to wait for me before things could progress.”

Eventually, frustrated by her reduced role in the decision-making aspects of the business, she left to go freelance.

“Going part-time was my own choice, so I feel fairly philosophical about the path I took,” said Scott, now 41. “But it is frustrating in a way when I compare my career to my husband’s. He’s been making steady progress over the last decade, while I’m probably stilla rung below where I was before I had children.”

Some organisations, however, seem keen to create the right environment for staff with family commitments. BT has a 97% return rate for women after maternity leave and a reputation for promoting women to senior positions.

Dave Wilson, BT’s head of people and policy, said the ethos was as advantageous to the business as to the employees. “The statistics might say that one group is likely to have a higher turnover than another, but if you decide not to recruit from that group you reduce the talent pool,” he said. “Flexible working helps us to attract and retain the most talented people.”

It also saves BT about £500,000 a year in recruitment costs because it does not have to find and train replacements for the working mothers who might otherwise leave. Not all companies have the capacity for such flexibility, though. Smaller businesses inevitably find it harder to cope when a member of staff takes maternity leave and some concede that any further changes to the law could make them think twice about recruiting women.

“The real problem is the uncertainty,” said Mary Bough-ton, who runs a small herbal-medicine company that has a staff of 12. “Not knowing when or if an employee might return to work until the term is up has a huge impact.” She believes that Brewer’s fears are well founded.

“For small businesses a further extension of maternity leave might be very difficult to cope with. That could be the point at which the law designed to protect women really does begin to disadvantage them,” she said.

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