We all know working full-time and bringing up kids isn’t easy – but new research has highlighted just how tough it can be. 

Women who have two children and work full-time are far more stressed than child-free women who work the same hours, a new study suggests. And the effects are very similar in dads. 

Researchers found the level of biomarkers related to chronic stress – including stress-related hormones and blood pressure – were 40% higher in women were working full-time while bringing up two children than in those who didn’t have kids.

“Work-family conflict is associated with increased psychological strain, with higher levels of stress and lower levels of wellbeing,” the researchers said. “Parents of young children are at particular risk of work-family conflict. Working conditions that are not flexible to these family demands, such as long working hours, could adversely impact on a person’s stress reactions.”

[Read More: What flexible working looks like for me: 6 mums share their stories] 

The study, which was conducted by teams from the University of Manchester and the University of Essex, analysed data from more than 6,000 participants. It collected information on their working lives as well as readings of stress responses, including hormone levels and blood pressure.

While women with two children had 40% elevated stress levels, women working full-time and bringing up one child had 18% higher levels. 

Researchers also found women with two children who worked reduced hours through part-time work, job share and term-time flexible working arrangements had chronic stress levels 37% lower than those working in jobs where flexible work was not available.

But those working flexitime or working from home, with no overall reduction in working hours, had no reduction in chronic stress. 

The study looked mainly at women’s chronic stress levels, but did found that men’s stress markers were lower if they worked reduced hours, and the effect was about the same as for women. 

Any employee with 26 weeks of service with the same employer has the right to make a request to work flexibly – not just parents. Flexible working means altering the way you work – this could include changing your hours, either compressing them or changing to part-time or term-time only, or working wholly or partly from home.

For more information on how to request this, visit Working Families advice site.