As any parent of a new baby knows, sleep can be elusive and the abundance of advice about it can be overwhelming.
Sleep specialist Dr Bronwyn Sweeney shares some insight.
Parents put a lot of pressure on themselves to regulate their baby's sleep, Dr Sweeney tells Susie Ferguson.
"You go into this new job and there's no manual. There's no onsight coach or mentor, there's no pay, there's no sick leave. It's 24-7."
But erratic sleeping isn't always a problem to be solved, she says. On average, new babies sleep 14 to 16 hours in a 24-hour period, but anything from 9 to 19 hours is considered normal.
The first four-to-six weeks of a baby's life are about "revival and survival", Dr Sweeney says.
This is reflected in South American and Chinese culture in a six-week period in which "new parents are supported very intensely and closely to literally revive and survive".
In this period, parents should focus on recovering from the birth and establishing the baby's feeding - a need that comes before their need for sleep.
Observe your baby's temperament and any potential signs they're ready to sleep or feed as closely as possible, Dr Sweeney says.
It can take up to a year for a baby to settle into the two biological processes that drive sleep - sleep pressure and body clock.
To help regulate your baby's body clock, use the daytime to expose them to lots of natural light, face-to-face interaction and walks.
When it comes to strategies such as 'controlled crying' there are definite opposing camps, Dr Sweeney says.
"For some people, it's the worst thing you could ever do, for others it's a lifesaver."
She doesn't personally believe in enforcing strong behavioural strategies in the first six months of a baby's life.
"As a psychologist, I'm not in favour of the full-blown 'cry it out' because I think for little people it's really their only way of expressing that something is up. Part of [the baby's] job from a psychological perspective is to learn to trust the world and that someone will come for me."
Dr Sweeney wishes she'd known 30 years ago about active sleep and quiet sleep - two forms of sleep that parents tend to interrupt.
When babies are in 'active sleep', they snuffle, grunt, fart, stretch, pull faces and look like they're awake. 'Quiet sleep' is when they're so deeply asleep they look completely out to it.
Dr Sweeney advises parents to pause and check whether their baby is actually asleep before you do anything that might wake them.
"Say to yourself 'prove to me you're awake' before you dive in and do anything [that might wake your baby]."
Dr Bronwyn Sweeney is a Clinical Psychologist and honorary associate with the Sleep-Wake Research Centre and Massey University.