Levels of cortisol – the stress hormone – go on to peak at 8.15am as mothers and fathers head out of the door.

Chartered psychologist, Dr Simon Moore, analysed saliva samples from parents involved in the school run at five points throughout the day to study how well they coped.

He found that lingering stress affected them whether they returned home after dropping their children at school or headed to work.

The ‘stress hangover’ continued until around 2.30pm on average, according to the study, involving ten parents, for Allianz Insurance.

Dr Moore said: ‘Making sure parents are feeling as little stress as possible before they start the drive to school is crucial to ensuring road safety on the school run and there are lots that can be done to relieve stress.

‘Many stressed people don’t get enough sleep and taking the chance to ‘switch off’ and get an extra half an hour in bed can work wonders. Laughing also releases stress busting hormones that will help every family member to feel a bit better about the morning routine.’

Francesca Keefe of Allianz Insurance added: ‘We know that stress has a negative impact on driving behaviour and with over half (55%) of the UK’s children travelling to school by car it’s important that parents are doing what they can to relieve any unnecessary stress before they get behind the wheel.’

Rushing: Parents’ stress levels peak at 8.15am for mothers and fathers in the UK, and the ‘stress hangover’ continued until around 2.30pm on average

The company surveyed 1,000 parents with children between the ages of five and 15.

Almost a third (30%) said the school run could ‘mess up timings for the rest of the day’. One in four admitted it ‘sets their mood for the rest of the day – good or bad’.

Parents felt the best thing about the school run was spending time with their children (39%), hearing about their day on the way home (36%) and being organised and on time (29%).

Allianz Insurance also worked with Emily Leary, author of parenting and lifestyle blog, A Mummy Too, to create tips for families on the school run this week.

She said: ‘Put shoes, bags and coats in a reliable place upon arriving home so that there’s never the last minute panic as you hunt for a missing shoe.

‘Create a devoted drawer in each child’s chest of drawers for school uniform so they always know where to look when they are getting ready.

‘Make it the house rule that the kids have to have their uniforms on before they come down for breakfast.

‘Always check book bags after tea, to avoid missing school trip slips, or panic to make a World Book Day outfit in 30 minutes.

‘Create a shared family calendar, either on the wall, or on your phones/ computers so that everyone is always aware of changes and variations to the usual routine.

‘Once you’re ready to leave, have a little race to see who can get their shoes and coats on the fastest. This motivates the children to get off the sofa and to the door.’