A rise in the number of people working unsociable hours has resulted in many parents finding it difficult to secure childcare, a report has claimed.
The research showed that childcare provision has not adapted to the changing needs of shift workers, causing pressure for families.
Independent thinktank the Resolution Foundation analysed the figures, which revealed that nearly 70% of all parents who are employed conduct some work that is out-of-hours.
For families on low-to-middle incomes, 75% have at least one partner who works outside the traditional working day hours of 8am to 6pm.
When looking at higher incomes, the figure increased to 90%.
It is believed that the trend is due to the growth in jobs in the service sector, where staff are required to work nights and weekends, such as in shops, hotels and restaurants.
Those employed in health and social work also find themselves doing the job outside normal hours, the foundation said.
And it warned that the government's plans to reform support for childcare costs in the new "universal credit" – designed to simplify the welfare system – will reduce the help available for many parents.
More affordable and flexible childcare is critical to maintaining the living standards of families on low-to-middle incomes, the report argued.
Vidhya Alakeson, Director of Research at the Resolution Foundation, said: "More flexible and affordable childcare is critical to supporting choice."
The government defended its plans and said it had been working closely with relevant organisations and charities to formulate them.