Two out of five low-paid young parents who ask for flexible work arrangements are "penalised" with fewer hours, worse shifts and even losing their job, a new report says.
A survey of 1,000 young mums and dads by the TUC found that more than half of those working in low-paid sectors such as retail, hospitality and social care, did not know their employment rights, with many unaware of unpaid parental leave arrangements.
Many of those polled had to take sick leave or holiday to cover childcare, while some said they were prevented from leaving work in an emergency.
Issues such as flexible working and work-life balance did not apply to many of those questioned, said the TUC.
General secretary Frances O'Grady said employers needed offer parents a fair deal.
The TUC criticised the attitude of some employers, saying more than two out five men surveyed felt "stigmatised" at work because of needing flexibility for childcare.
The report said many young parents are penalised if they ask their employer for flexible working arrangements, telling the TUC they are subsequently given fewer hours, worse shifts or even lose their job.
Ben Wilson, Equality and Human Rights Commission executive director, said there needed to be a change in workplace culture.
A Business Department spokesman said: "The continued strength of our economy is built on the flexibility of our labour market, benefiting both business and workers and leading to record levels of employment.
"But that flexibility needs to work both ways which is why we commissioned Matthew Taylor to review modern working practices to ensure our employment rules and rights keep up to date to reflect new ways of working. We are considering his report carefully and will respond in due course."