While new parents might expect to sleep a whole lot less in those first few months after bringing home their baby, a new study suggests that sleep deprivation can actually last for years.
University of Warwick research, published in the journal Sleep, found that after welcoming their first bub and for up to six years after their birth, mums and dads "sleep duration and sleep satisfaction" don't fully return to pre-pregnancy levels.
To reach this truly horrifying, but oh-so accurate conclusion, the team explored the sleep patterns of 4,659 parents who had a baby between 2008 and 2015.
And the results were ... interesting.
In the first three months post birth, mums slept on average one hour less than before pregnancy, while dads' sleep on average decreased by 15 minutes. Yep - fifteen minutes.
"Women tend to experience more sleep disruption than men after the birth of a child reflecting that mothers are still more often in the role of the primary caregiver than fathers," said lead author Dr Sakari Lemola.
As their children grew older, however, things improved - ever so slightly. By the time kids were four - six years old, mums' sleep duration was around 20 minutes shorter than pre-kids, while dads clocked 15 minutes less than before.
"While having children is a major source of joy for most parents it is possible that increased demands and responsibilities associated with the role as a parent lead to shorter sleep and decreased sleep quality even up to 6 years after birth of the first child," Dr Lemola says.
Sleep effects were more pronounced in first-time parents compared with experienced parents, and in breastfeeding compared with bottle-feeding mothers.
"After the second and third child, the effects on maternal sleep satisfaction are less pronounced than after the first child," the authors write. "In contrast, maternal sleep duration shows a similar magnitude of change regardless of whether it was after the first, second, or third child."
In other words, we still get less sleep but maybe we expect it, so it's not quite so bad?
But why are our kids keeping us awake at night, long after they're out of nappies?
"Causes of the long-term decrease in sleep satisfaction and duration till six years after birth may involve changes in duties, strains, and worries related to the parental role even when children are older," the authors write.
And while they had hoped to uncover some factors that might be protective against sleep disturbance, sadly, they came up short - neither higher income, nor "dual parenting" buffered against the decrease in either sleep satisfaction or duration.
That said, the authors believe their study has important implications.
"Because sleep plays an important role for adjustment and mental health during pregnancy and postpartum, it is an important task for future research to examine ways to protect sleep satisfaction and duration in this stage of the life cycle," they write.
"Furthermore, advice and support should be routinely provided for new parents preparing for childbirth, towards managing their postpartum sleep expectations and to encourage them to take precautions to reduce risks from the effects of sleep fragmentation and deprivation."
Easier said than done ...