At least 1,000 of the 3.8 million women who have been forced to wait up to an extra six years to get their pensions marched to parliament on Wednesday.

Around their necks were photographs of hundreds more women hit by the change in state pension age (SPA) who could not be at the march because they could not afford the travel costs, work on zero-hour contracts, or do menial jobs that would not give them the time off.

Yet more photographs were worn in memory of other women who had died while still waiting for the government to give them the pension they paid into all their lives with the promise that they would be able to claim when they turned 60.

“These changes to the state pension age for women were cynical exercises by both a Tory and a coalition government to raise £30bn from 3.8 million women,” said Sophie Walker, the leader of the Women’s Equality party, who attended the march along with other MPs, politicians and campaigners.

“Many of these women didn’t find out about the pension changes until they literally went to get their pension or finally got sent an official letter 16 years after the change had been made, leaving them with no time to make alternative financial arrangements.

“We’re not talking about the baby boomers,” she added. “We’re talking about women who stepped out of the workplace repeatedly to do unpaid caring work for their families and the government just banked that unpaid work and took their pensions. These women have been tipped into impoverishment. It’s grossly unfair.”

Women in their 50s and 60s have been hit by the government’s decision to increase the female state pension age from 60 to 66: some have lost their homes, while many continue to experience extreme stress and hardship. A recent survey by the pressure group BackTo60 found that a significant proportion of respondents reported feeling suicidal, had attempted to take their lives, or had self-harmed.

“We feel that the government thought our demographic was low-hanging fruit that they could pick off without a fight,” said Joanne Welch, one of BackTo60s representatives. “But there’s an increasing groundswell of fury coming the government’s way because these women are becoming politicised – and because increasing numbers are only now discovering they’re going to be affected; there are still women out there who don’t know their pension age has been set back.”

BackTo60 promise this march is just the start. They have a date for a judicial review, led by Michael Mansfield QC, which will seek to force the government to reverse its decision.

‘What’s happened to these women is atrocious.’ Photograph: Penelope Barritt/Rex/Shutterstock

“The government badly underestimated us,” said Welch. “We’re now not only pursuing the judicial review, but we’re mounting a new battle arguing that the UK Equality Act 2010 is discriminatory for women because the government hasn’t incorporated a United Nations convention into it.”

In a submission on Tuesday to the House of Commons women and equalities committee, Jackie Jones, a professor of feminist legal studies at the University of the West of England, argued the same point. She said that UK legislation “is limited, needs reform, and does not and cannot address many inequalities, especially intersectional inequalities”.

She highlighted the Amicus Brief she submitted to BackTo60s judicial review. “In general terms, the mechanisms chosen and their consequent negative impact on women born in the 50s, breach the UK’s international law obligations under the Convention on the Elimination of all Forms of Discrimination Against Women (CEDAW).”

An international bill of rights for women, CEDAW was adopted in 1979 by the UN general assembly, instituted in 1981, and ratified by 189 states.

In her submission to the MPs’ inquiry into the Equality Act 2010, which aims to understand what more needs to be done to achieve widespread compliance, Jones argued that the UK government “steadfastly refuses to incorporate CEDAW into the Equalities Act 2010, or pass a separate act that would provide women with the rights and fundamental freedoms the UK pledged on the world stage to adhere to over 30 years ago”.

Yvette Greenway, one of the leading figures in the campaign, said: “What’s happened to these women is atrocious – and the fact that it could happen in this day and age is astonishing. How much worse does life have to get for these women for the government to show some humanity?”

Case studies

Anna, Plymouth, Devon, 59

“I worked for the DWP for 36 years until 2011 and spent time in a job centre around the time the changes in state pension age were being suggested and introduced. Being on telephony, I expected we would be given guidance, as I was sure there would be an increase in inquiries – but nothing was said and no memos given.

“Although the information was on our intranet, which only DWP staff could access, there was no mention of a mail drop to customers who may be affected. Up to my leaving the DWP, as far as I am aware, there was no letter campaign for the change in SPA.”

‘This is not equalisation’ Photograph: Martin Godwin

Gill Priest, Northamptonshire

“Had women born in the 50s been given a level playing field to start with, this may not have been so catastrophic. But our generation has not been offered the opportunities to earn as much as men (the recent gender pay gap statistics prove this is still not equal), join pension schemes, enjoy equal opportunities to progress in education, and within the workplace, support with childcare or rights to spouses’ pensions. Even the NI system of contributions itself was not equal.

“It is all very well saying it is equalisation, but this needs to be introduced when women have been given opportunities to make financial provisions – not like this; this is not equalisation. How can it be? It is like starting a 100-metre sprint in a lane filled with potholes and obstructions whilst everyone else has a clear lane.”

Frances Kew, Edinburgh

‘I have never claimed any benefits in my life’ Photograph: Self-portrait

“I have worked hard all my life, since the age of 16. In the runup to 2011, when I took voluntary retirement, I’d checked the HMRC website regularly. It stated quite clearly that I’d retire on my 60th birthday on 5th February 2020. Otherwise, I’d never have taken early retirement, as my voluntary early retirement lump sum was only enough to get me through those nine years. The actual basic work pension I have is a pittance. I am now having to live off my husband, who’s on minimum wage.

“Two years after I took early retirement, in 2013, I got a letter from the DWP to say my state pension age would now be on my 66th birthday, 5th February 2026! It was a bolt out of the blue. To add insult to injury, when I looked on the official government site, I saw that I was no longer entitled to my full state pension either as I stopped working before I was 66.

“I have never claimed any benefits in my life. I have always worked for everything I have. Now I find myself in desperate circumstances, wondering if I am going to have to sell my home, which I have worked for all my life.”