Image copyright Getty Images Image caption Women say being left short of money by universal credit is forcing them to make desperate decisions

"I would drop my son off on a Friday and start to get goosebumps thinking, 'I know what I've got to go and do tonight'."

Alison says she became a prostitute as a last resort after being left short of money by universal credit.

Her story is becoming familiar to the group of MPs looking into "survival sex" - women being forced into sex as a result of the changes to benefits.

"This is something that shouldn't be happening in a wealthy nation," says independent MP Heidi Allen, who's on that Work and Pensions Committee.

"I'm shocked, embarrassed and I'm angry."

Universal credit helps with living costs, replacing six benefits including housing benefit and child tax credit.

But since its introduction in 2013, it's been accused of making things harder for people receiving it.

Alison had her son - who is disabled - when she was 18 years old and has relied on the benefit system to support them both.

"There are some weeks after you've paid your bills, you don't have enough and you think, 'I have to do it'."

Image copyright Getty Images Image caption An inquiry is looking into claims that women on universal credit are being forced to rely on sex work to survive

Alison is matter of fact about the situation.

She says making money to support herself and her son was always the priority, but admits the experiences have left her traumatised.

"I always have lots of showers. Once there was this guy, I could smell him on me afterwards - a big, disgusting man.

"He said he deliberately didn't wash for a week because he wanted to be near a woman that's clean. It's disgusting.

"One guy, his mum opened the door and he was in the shed in the back trying to make me do drugs, so I had to escape."

She pauses.

"I do get scared of dying - some men take things to a whole other level."

The Work and Pensions Committee - chaired by independent MP Frank Field - launched an inquiry in March after listening to the concerns of charities.

The English Collection of Prostitutes - which campaigns for the safety and decriminalisation of sex workers and has often linked universal credit to sex work - has given evidence to the group.

Image copyright PA Image caption Heidi Allen says she quit the Conservative Party because "they've got it wrong" on universal credit

Heidi Allen says she quit the Conservative Party earlier in the year because of the party's rollout of universal credit.

"The welfare state should be there to pick you up when you are at your lowest.

"At the moment rather than a net that's holding people up, it's dragging them down and that's the bit we need to change."

Around 700,000 lone parents miss out on an average £2,380 per year because of universal credit, the Institute Of Fiscal Studies says.

Research economist Tom Waters says it's to do with timing: "You have to wait at least five weeks now to get your first benefit payment.

"Although the government has made advances available for that period, that can be a difficult time for people that don't have many other resources to draw on."

Image caption Many users with computer access say the "confusing" online system makes the process even more difficult

Alison says having a disabled son to care for makes it harder for her to find a job that fits her schedule.

"The government needs to get a system in where they can put enough money in people's banks.

"They really need to understand we're not like them - we haven't got loads of money."

'The testimonies changed my mind'

Mrs Allen and Frank Field have been "humbled" by what people have shared with them around the UK.

Both will be making recommendations to Secretary of State for Work and Pensions Amber Rudd, but Heidi Allen is worried.

"Amber's the best on this and gets it, but when we have a new Prime Minister [on 23 July] all the ministers will probably change.

"We could be back to the drawing board again."

Image copyright www.parliament.uk Image caption Women have given anonymous evidence to a committee looking into the scale of the problem

"What changed my mind was hearing the testimony of some of the women in front of the committee," says MP Will Quince, a minister for family support at the Department of Work and Pensions.

He'd originally dismissed the link between sex work and universal credit as "anecdotal" but has now done a U-turn.

His job isn't safe either but he says that won't stop him from raising awareness.

"Don't underestimate our determination - even if I'm on the back benches we will continue to be a champion on this and other issues because we feel strongly about it."

Alison has not given evidence to the inquiry over fears of social services being alerted - which the commission has reassured won't happen.

However, she says she's stopped doing sex work due to being in a loving relationship.

"I'm still on universal credit and my partner helps to looks after me and my son."

She goes quiet for a bit when asked if she'd ever return to sex work to make ends meet.

"Honestly, I dread thinking about if we ever split up and it's just me and my son.

"I'd have no choice, really."

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