12 Month Sleep Regression: Why Your Baby Is Sleeping Badly Now and What Helps

What Is the 12-Month Sleep Regression?

“Sleep regression” is not a medical term and not a diagnosis. Parents use it for a phase in which a baby who was sleeping reasonably well suddenly wakes more often at night, settles less easily, or fights naps. For this article we went through the information from the AAP (HealthyChildren.org), the NHS, the CDC and Germany’s BIÖG (kindergesundheit-info.de). None of them describes a “12-month sleep regression” with a fixed start or a fixed length. So you will not find a number of weeks here, only what the sources actually say about this age.

Why Is My Baby Sleeping Badly at 12 Months?

Around the first birthday a lot happens at once. These are the points the sources name:

• New movement skills: For 12 months the CDC lists pulling to stand, walking while holding furniture and picking up small things between thumb and pointer finger.
• New skills in the head: According to the CDC, 12-month-olds look for things they see you hide (such as a toy under a blanket), wave bye-bye, call a parent “mama” or “dada” and understand “no”. At 9 months, the CDC says, a baby already looks for objects dropped out of sight.
• Separation anxiety: According to the AAP, separation anxiety can cause many nights of disrupted sleep from the second half of the first year; a child may wake several times and cry for one or both parents, often preferring one. The AAP says it usually fades somewhere around the second birthday.
• Teething and hunger: The NHS says teething pain and hunger can disturb sleep; growth spurts and illness can also affect it.

Whether any of these is the trigger for your child cannot be told from outside. That developmental steps directly disturb sleep is not shown in the sources we checked; it is a common observation among parents.

My Baby Keeps Waking at Night at 12 Months. Is That Normal?

As a rough guide, Germany’s BIÖG says most babies can sleep six to eight hours at a stretch by the end of the first year, and many do. The reverse is also true: waking is not ruled out. For the time after the first birthday the NHS gives a total sleep need of around 12 to 15 hours, and how those hours are spread across night and day differs from child to child. A single bad night is not yet a “regression”. It is more worth your attention when sleep changes noticeably over several days and also affects mood or the daily rhythm.

How Long Does the 12-Month Sleep Regression Last?

There is no reliable number; none of the sources we checked gives one. What is documented is this: the AAP says the separation-anxiety stage can last for several months and usually fades somewhere around the second birthday, and that in the meantime your child may need reassurance several times a night, night after night. That is not a statement about “the regression”, but it shows patience may be needed. Such phases are usually temporary. If sleep stays poor for a long time or you are worried, talk to your pediatrician rather than waiting for a date.

Baby Sleeping Badly: What to Check First

Before assuming a sleep regression, it is worth looking at the simple causes the sources name:

• Hunger: According to the NHS, babies can wake at night because they need to be fed. Over time you learn whether your baby is really hungry or just woke up (BIÖG).
• Temperature: The NHS says being too hot or too cold can also disturb sleep.
• Teething and illness: Teething pain and illness can affect sleep (NHS).
• Diapers: Germany’s BIÖG notes that a baby does not need a diaper change after every night feed.
• Daily rhythm: Do wake windows and the evening routine still suit your baby’s age? More on that below.

If you find nothing here and sleep stays worse for several days, a conversation with your pediatrician is the next step.

What Helps With the 12-Month Sleep Regression?

• The same evening routine: The NHS suggests a simple, soothing bedtime routine with dimmed lights and little excitement just before bed, since too much stimulation can wake a child up again. Germany’s BIÖG describes a repeating evening ritual of around 30 minutes, ending with a goodnight kiss, as calming and reassuring.
• Respond calmly at night: The BIÖG advises first soothing a waking child with your voice and comfort for a few minutes instead of lifting them straight out of bed. A child does not need entertainment at night.
• Practise goodbyes: The AAP suggests telling your child matter-of-factly when you are leaving, offering a short distraction and then going promptly. Children usually accept separations more easily when they are part of a predictable routine.
• Check wake windows: Do the gaps between sleeps still suit your child’s day? See the 12-month-old sleep schedule for an overview by age.
• Keep notes: Log sleep, feeds and diapers for a few days. It makes patterns visible and helps in a conversation with your pediatrician.

In the first year, sleep is on the back, on a flat surface, in the baby’s own sleep space (AAP).

When Should I Talk to a Pediatrician?

Talk to your pediatrician whenever you are worried. Specific prompts from the sources:

• The AAP lists, for night waking: your baby is not growing and gaining weight steadily, is not feeding well, or has noticeably different wet or dirty diapers than usual.
• The BIÖG advises talking to a doctor if a child shows no signs of a regular sleep-wake rhythm after the sixth month and is hard to settle.
• The NHS says to speak to your health visitor if your baby has problems sleeping or you need more advice about a routine.

The Neighbouring Phases

For what comes before and after, see the 9-month sleep regression and the 18-month sleep regression. For every age at a glance, see our complete sleep regression guide.

Frequently Asked Questions