Older women are being "frozen out" of the jobs market because of caring responsibilities, leading to calls for more to be done to help them work flexibly.
A study by charities Age UK and Carers UK found that the proportion of older women working flexibly has fallen over the past two years, while there has been a "marked increase" in the number unemployed for more than a year.
The report suggested that many older women wanted to work, but could not find a suitable job.
An analysis of the Labour Force Survey found that 36% of women worked flexibly in 2012, down from 38% in 2010.
In the same period, long-term unemployment among women aged 50 to 64 increased from 34% to 40%.
Caroline Abrahams, of Age UK, said: "We know that many older women especially are finding it impossible to hold down a full time job at the same time as fulfilling their caring responsibilities.
"In the end, many have to stop employment altogether or take a poorly paid part-time job, where their skills are often wasted and their income plummets.
"That's why we need Flexible by Default, so that everyone can work flexibly unless their employer can justify otherwise, to harness the wasted potential of many older women - and indeed older men."
"Unless carers can access flexibility at work and reliable care services at home they are at risk of being forced to give up work entirely, with serious costs not just to their family finances but also to their employer and the economy."