Working for nine-plus hours a day could put women at higher risk of depression, but not men finds a study.

Women who worked extra-long hours, more than 55 hours a week, had 7.3 per cent more depressive symptoms than women working a standard 35-40 hours a week.

However, the same was not the case in men, the study found. “This is an observational study. Although we cannot establish the exact causes, we do know many women face the additional burden of doing a larger share of domestic labour than men, leading to extensive total work hours, added time pressures and overwhelming responsibilities," said lead researcher Gill Weston, a postdoctoral student at the University College London.

"Additionally, women who work most weekends tend to be concentrated in low-paid service sector jobs, which have been linked to higher levels of depression," Weston said.

For the study, published in the Journal of Epidemiology and Community Health, the team included 11,215 working men and 12,188 working women.

The study also showed working on weekends was linked to a higher risk of depression among both men (3.4 per cent) and women (4.6 per cent).

Two-thirds of men worked on weekends compared with half of the women. Those who worked all or most weekends were more likely to be in low-skilled jobs and were less satisfied with their job and earnings than those who only worked on weekdays or some weekends.

"We hope our findings will encourage employers and policy-makers to think about how to reduce the burdens and increase support for women who work long or irregular hours -- without restricting their ability to work when they wish to," Weston said.

"More sympathetic working practices could bring benefits both for workers and for employers of both sexes," she suggested.

- IANS