Thousands of women in their fifties and sixties have been left destitute as changes to the state pension age leave huge holes in their finances – with the worst hit driven to self-harm and contemplating suicide.

Ministers have been urged to take action as research shows the decision to increase the female state pension age from 60 to 66 – and lack of awareness over the change – has had a detrimental effect on many women born in the 1950s.

Around 2.6 million women were affected by a law in 2011 which pushed forward plans to increase their state pension age to equal to that of men – but many were never made aware of this.

The results of a survey undertaken by charity Silence of Suicide for the Backto60 campaign group shows that almost half of the 873 respondents have self-harmed because of the stress and hardship caused by the pension reform.

A large proportion (46 per cent) also reported having had suicidal thoughts as a direct result if the pension deferral, with 70 women saying they have attempted to take their own lives.

Politicians and campaigners said the findings demonstrated an “unforgivable” failure by successive governments to consider the impact of the change and inform those who would be affected by it, and accused ministers of “overlooking” their needs.

A number of affected women have sent letters to The Independent, with one saying she had been “systematically robbed” of six years’ pension with “no official notice of the rise in pension age”.

Another woman, Carol May, from Hertfordshire, who found out about the change when she was 59, said she was now having to “go without food in order to pay bills” and had contemplated taking her own life.

“I’ve worked my whole life, paid over 40 years’ worth of national insurance contributions – yet I feel like I’m on the scrap heap,” said the 63 year old.

“I was in a place where I was divorced after a very long marriage and my husband was three years older so had been able to claim pension credits. Now I was going to have to wait another six years for my pension.

“I want to contribute to society, but I can’t do the job that I did when I first left university. I’ve had interviews but I just haven’t got the job. Nobody wants you at my age. The only jobs I’ve been offered are part-time, so I wouldn’t be any better off.

“I go without food in order to pay bills. I’ve used a food bank a few times. I’ve often thought, it’s not worth being here, I might as well kill myself.”

Figures released in response to a parliamentary question last month revealed that the government’s complaints team was dealing with 3,214 complaints from women born in the 1950s regarding changes to state pension.

The State Pension Inequality for Women Committee has tabled a private members’ bill in a bid to push the government to review pension arrangements for women who have or will be financially disadvantaged by the changes.

Labour MP Carolyn Harris, who chairs the committee, said the latest findings were indicative of what she heard every day, saying women were “desperate, and in some cases destitute”.

“There’s not a day goes by when I don’t hear from at least one woman. It’s constant,” she said.

“They planned their finances; they planned to retire; they had jobs which they couldn’t physically do after a certain age, but they hung on there until they were 60.

“It’s one of the most prolific issues that come into my postbag. Not just from my constituents, but from women all over the world, because you have women who live in other countries who are British.

“It’s bigger than Brexit in my office. It’s a bigger issue than anything else.”

Ms Harris described cases of women sending each other £20 notes in the post so that they can buy food and the MP said she was facilitating food parcels for affected women in her constituency.

She added: “What really scares me is how many people don’t know that they’re not going to get their pension. And only realising when nothing comes through. It’s shocking.”

Yvette Greenway, chief executive of Silence of Suicide, said: “For a lot of women there was no notice at all, or very little notice. The financial arrangements they’d planned for all their working lives no longer stood.

“Is it any surprise that we now have women who are left in a state of absolute torture, not knowing what to do? It’s unforgivable and the most callous of cruelties. Their needs have been overlooked.

“These women have paid into the pot and entrusted to successive governments to look after and to give back to them at a time in their lives when they should be able to slow down and relax a little. It is a scandal.”

A Department for Work and Pensions spokesperson said: “The decision to equalise the state pension age between men and women was made over 20 years ago and achieves a long-overdue move towards gender equality. As we are all living considerably longer than when pensions were introduced, we need to adjust the pension age to ensure the sustainability of the state pension now and for future generations.

“We have thoroughly reviewed the options for equalising the state pension age, listening to concerns along the way. As a result, we have spent an extra £1.1bn to ensure that nobody will reach the state pension more than 18 months beyond when they would have done under the original 1995 Pensions Act timetable.”

If you need support you can contact Silence of Suicide at info@sossilenceofsuicide.org or the Samaritans by calling them for free from any phone for free on 116 123, email jo@samaritans.org.