"You Should Sleep When the Baby Sleeps"

What people believe

That the solution to postpartum sleep deprivation is simple: nap when the infant naps. This advice is offered universally and with good intentions. It implies that the opportunity to sleep is available and that the only barrier is the mother choosing not to take it.

What the evidence says

The underlying biology is sound. Any sleep — including fragmented naps — contributes to total sleep duration, and total sleep duration is what matters most for cognitive function and mood regulation.¹ In that sense, sleeping when the baby sleeps is good advice in principle.

In practice, it is often impossible. The infant's nap may be the only window to eat, shower, manage household tasks, care for older children, respond to work communications, or attend to the administrative demands that do not pause for a newborn. For mothers recovering from caesarean section or significant perineal trauma, basic physical tasks take longer and leave less time for rest.

Postpartum hypervigilance — a physiologically driven state of heightened alertness to the infant's cues — can prevent mothers from falling asleep even when the opportunity exists. A 2024 study on postpartum psychological disorders found significant associations between anxiety, sleep quality, and feeding method, highlighting that the barriers to sleep are frequently physiological and psychological, not behavioural.² When a mother cannot sleep despite opportunity, this may indicate postpartum anxiety or insomnia warranting clinical assessment rather than continued advice to "just sleep."³

What to do instead

Rather than a blanket instruction, offer practical sleep strategies: protect at least one consolidated four- to five-hour block through shift-based feeding; prioritise total sleep duration over uninterrupted sleep; reduce daytime demands where possible; and screen for insomnia or anxiety if a mother reports being unable to sleep even when the opportunity exists. Acknowledge that the advice, while well-meaning, does not account for the structural realities of postpartum life.