Working mothers are among those who apparently suffer the most from employment inequality.
That may not come as a surprise to many women who have spent years struggling to strike a balance betweeen their career and the demands of motherhood.
By Jo Coburn
BBC News political correspondent
The final report by the Equalities Review, commissioned by Prime Minister Tony Blair and published this week, found that women faced "outdated" attitudes that implied mothers were less reliable workers.
Some female MPs say sacrifices have to be made in Parliament
One solution put forward is more flexible work for women as well as for men.
Good in theory perhaps, but some of the country's oldest institutions are finding it hard to adapt.
I talked to three women MPs about the sacrifices that have to be made for a successful career in Parliament.
Liberal Democrat MP Lynne Featherstone is a relative newcomer.
She won her north London seat in the 2005 general election and says she doesn't know "how women with young children manage in the House of Commons".
She is a single mum but her daughters are now teenagers. When she started out as a local councillor, she had to pay a babysitter every time she went to a meeting.
Now she says life is easier, but that the atmosphere in the Houses of Parliament is like a "boys public school with testorone flying around".
She says the combative style of politics in the chamber may well be off-putting to women.
She balances it all by saying that the job of an MP is fantastic and worthwhile and sets a good example to her daughters - even though the sacrifices have been great.
Ms Featherstone admits "when there is a clash between the school play and election day as there was on one occasion, the former loses out and you have to harden your heart."
To try and combat the pressures of work and family life, there have been attempts to change MPs working hours, but it has proved extremely difficult.
Labour MP Ann Coffey is a member of the Commons modernisation committee and says it is currently looking at the issue of time management at Westminster.
MPs have been encouraged to submit their thoughts in writing in support of any change to the system. So far, she says, there has been little response.
In her opinion, the Commons should run from 9am to 5pm four days a week rather than the current system of 2.30pm starts on Mondays and Tuesdays, and 10pm finishing times when there is a late vote.
But the Labour MP is doubtful such changes will ever be introduced because Parliament is so steeped in tradition.
Caroline Spelman says motherhood makes you a better politician
For the Tory MP and shadow for the Office of the Deputy Prime Minister, Caroline Spelman, it's a matter of being brave and demanding what you want in terms of flexible working.
She recently broke with parliamentary tradition and asked permission in the chamber to leave early from a debate so she could take her son to a hospital appointment.
Her request was granted. She believes that motherhood gives you a different perspective on life in Parliament and makes you a better politician.
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