As most men and women know only too well, sleep deprivation and parenthood go hand-in-hand.
Night feeds, wailing infants and waking up with worry about their precious cargo can leave parents severely sleep-deprived but have you ever stopped to consider just how much shut-eye you're losing as a result of giving birth?
According to the Daily Mail, a fascinating new calculator will reveal your sleep loss dependent on how old your children are to show your weekly, monthly, and yearly deprivation - and it may shock you.
The tool also reveals how many nappies you've changed, how many bedtime stories you've read and how many lullabies you've sung
For example, if your child is 12 months old, you have apparently lost 1,836 hours of sleep, which is the equivalent of 77 days , which is a shocking three months' worth of sleep lost.
The calculator, created by hillarys.co.uk, also reveals that if your child is three years old, you've lost 6,660 hours of sleep, which equates to 278 days or a startling nine months.
In that time you will have changed 11,880 nappies, read 294 bedtime stories and sung 8,760 lullabies.
HOW THEY CALCULATE IT
A spokesperson said: "Research was carried out to determine how much sleep new parents lost per night during the first 12 months, up to 18 months, 24 months and then past that.
"The averages are then used, whilst also taking into account multiple children, to give parents a rough idea of how much sleep they've lost since becoming a parent."
Sleep lost
5.1 hours a night in the first 12 months
4 hours per night 12months -18months
3.45 hours per night 18-24months
Nappies changed
12 a day first 3 months
8 a day 3-18 months
5 a day 18-24 months
Lullabies
4 a night until 3 years old
Bedtime stories read:
3.5 a week until 7 years old