Three times more young women are employed in low paid, low skilled jobs than 20 years ago, according to a new study by the Trades Union Congress (TUC).
The TUC said the proportion of 16 to 24-year-old women in jobs such as office and hotel cleaning has increased from 7% to 21%, while the figure for young men has increased from 14% to 25%.
The research also showed that gender plays a huge part in career choice, with only 1% of women working in skilled trades compared with a fifth of young men. Four times as many young women worked in occupations such as hairdressing, leisure and travel, said the report.
Up to 50,000 people are marching through Manchester to demonstrate against austerity cuts on the opening of the Conservative Party Conference.
Police said the union protest was now a mile long as it snaked through the city centre, bound for a rally where union leaders will deliver a series of speeches condemning the impact of Government policies on jobs.
The marchers are also protesting against the "rapid sell-off" of the most lucrative parts of the NHS to private healthcare companies and spending cuts across the health service.
Ed Miliband will stick by his controversial reforms of the party's links with unions, saying they will create a stronger Labour party, with a better chance of winning the next election.
In his speech to the TUC, Mr Miliband will acknowledge that some people are worried about change.
"It means we could become a Labour Party not of 200,000 people, but 500,000, or many more. A party rooted in every kind of workplace in the country, a party rooted in every community in the country, a genuine living, breathing movement.
"It will be a massive challenge for the Labour Party to reach out to your members in a way that we have not done for many years and persuade them to be part of what we do, and, like anything, that is hard, it is a risk. But the bigger risk is just saying let's do it as we have always done it."
Speaking ahead of her appearance at the TUC conference, Deputy Labour leader Harriet Harman said at a local level the relationship between the party and the trade unions is "in practice, not working at all".
She added there is not much connection between the party and members at this level and "that is what Ed Miliband wants to change".
Shadow business secretary Chuka Umunna has rejected suggestions a cut in union funding would mean financial meltdown for Labour.
Speaking to the BBC Radio 4 Today programme, he said: "For us as parties, we've fundamentally got to change the way we operate if we are to make our parties relevant in the 21st century.
"Part of that involves making sure we've got a better connection with our communities and our people. I think the trade union link gives us a huge head-start over other parties in that respect, because it gives us a direct link to three million working people.
"What we are seeking to do is to ensure that we've got a better link to individual members."
Mr Umunna added: "Undoubtedly, we are going to take a hit in terms of our finances, but that doesn't mean that it isn't the right thing to do."