Crying babies can frazzle your bank balance, as well as your nerves...
The sleep deprivation experienced by parents with a newborn not only frazzles their nerves, but can also seriously harm their bank balance, a study suggests.
Researchers from the London School of Economics (LSE) found that when parents are frequently woken by babies they are less likely to hold down a job, more likely to work shorter hours and consequently earn less than before the birth.
In fact, just one hour less sleep each night can reduce household income by up to 11pc, say the study authors.
Dr Joan Costa-Font, Associate Professor in Political Economy at the LSE, said new parents should factor in the lower earnings.
"Lack of sleep is responsible for human fatigue, and can undermine economic performance," said Dr Costa-Font who presented the research at the Royal Society of Economics' annual conference in Bristol yesterday.
"Sleep is often overlooked in economics models despite its obvious restorative effects on human health alongside influence on brain plasticity and feelings of well-being.
"Having children reduces productivity and I think parents and government should factor this in, and hence they need to be compensated for it to make it worthwhile. Lower-income people are more strained by time and income. So they would be impacted the most."
To find out the impact of sleep deprivation caused by crying babies, researchers looked at data from the Avon Longitudinal Study of Parents and Children which has been running since the 1990s, and involves more than 14,000 families.
It contains records of parental sleep and how much a child wakes up during the night, as well as employment status, the number of hours worked, job satisfaction and household income over time.
The study found a strong relationship between the number of times a child woke up in the night and income over time. As parents achieved less sleep at night, so their incomes plummeted.
Although parents expect their wealth to suffer when they have children, the new study suggests that lack of sleep is adding to the strained finances which come with raising a child.
"To our knowledge, this is the first paper that finds a link between child sleep quality and parental economic performance," co-author Dr Sarah Fleche said. "Fathers are somewhat less affected by child sleep problems. Low-skilled mothers instead experience a large decrease in employment and the number of hours worked when facing sleep deprivation."
A recent study estimated the impact of lack of sleep on the productivity of the British workforce costs businesses there up to £40bn (€47bn) each year.