Sleeping

• The Moro or ‘startle’ reflex is an involuntary response where newborns suddenly throw their arms out, arch their back, and cry when they feel like they're falling or hear a loud noise, serving as a primitive survival mechanism. 
• Startle reflex typically disappears between 3 to 6 months of age as your baby's nervous system matures and movements become more controlled. 

• Swaddling effectively reduces startle reflex by keeping baby's arms secure close to their body, mimicking the womb's comfort and preventing their own movements from waking them. You can also minimise startling by moving slowly when handling baby, creating a calm low-noise environment, using white noise to mask sudden sounds, and maintaining consistent routines.

If you've noticed your newborn suddenly throwing their arms out wide, arching their back, and perhaps letting out a little cry, you've witnessed the startle reflex in action.  

While it can be alarming for new parents, this reflexive response is completely normal and actually a sign of healthy neurological development. 

Let's explore what the Moro reflex is, why it happens, and most importantly, how you can help your little one feel more secure when it occurs. 

What is a startle (Moro) reflex? 

The startle reflex, also known as the Moro reflex, is an involuntary response that newborns display when they feel as though they're falling or are startled by a loud noise or sudden movement.  

It’s named after Austrian paediatrician Ernst Moro and is a primitive reflex that’s one of several automatic responses that babies are born with. 

When their Moro reflex is triggered, you may see your baby: 

• Throw their arms out to the sides with palms up and thumbs flexed 
• Arch their back and extend their legs 
• Cry out or appear distressed 
• Bring their arms back in toward their body 

The entire sequence usually lasts just a second or two, but it can be enough to wake a sleeping baby or cause them to become unsettled.  

This reflex is an evolutionary survival mechanism designed to help babies cling to their caregivers when they sense danger or instability. 

When does startle reflex go away? 

Most babies will naturally outgrow the Moro reflex between 3 to 6 months of age. As your baby's nervous system develops and matures, their movements become more controlled and purposeful, and primitive reflexes like the Moro reflex gradually fade. 

How long do newborns have startle reflex? 

The startle reflex is present from birth and typically begins to diminish around 3 months of age. By 5 to 6 months, most babies will have completely lost this reflex. If their Moro reflex lasts beyond 6 months, it's worth mentioning to your healthcare provider. 

The disappearance of the startle reflex is actually a positive developmental milestone, showing that your baby's central nervous system is maturing properly. 

How can you help startle (Moro) reflex? 

While you can't prevent the Moro reflex entirely (it's a natural and healthy response), there are several gentle strategies you can use to minimise startling and help your baby feel more secure: 

• Create a calm environment: Keep noise levels low, especially during nap time and bedtime. Use white noise machines to mask sudden sounds that might trigger the reflex. 
• Move slowly and deliberately: When picking up or putting down your baby, make your movements smooth and gradual. Support their head and body fully during transitions. 
• Use gentle wake-up techniques: If you need to move your sleeping baby, place a gentle hand on their chest or tummy first to provide reassurance before lifting them. 
• Establish a consistent bedtime routine: A predictable routine helps your baby feel secure and may reduce the frequency of startling episodes. 
• Maintain a comfortable sleep environment: Ensure the room temperature is comfortable and your baby isn't too hot or too cold, as discomfort can increase restlessness and startling. 

Does swaddling help startle reflex? 

Yes, swaddling can be incredibly effective in managing the startle reflex. When done safely and correctly, swaddling provides the gentle containment and security that many babies find soothing. The snug wrapping mimics the cosy environment of the womb and can help prevent your baby's flailing arms from triggering the Moro reflex or waking them from sleep. 

Benefits of swaddling for startle reflex:  

• Keeps baby's arms secure and close to their body, reducing the intensity of the startle response 
• Provides a sense of comfort and security that can help babies sleep longer 
• Creates a consistent, womb-like environment that many newborns find calming 

At Tommee Tippee, we offer a range of swaddles with different TOG ratings. Our sleepwear is designed with your baby's comfort and safety in mind, and to help you both sleep better. 

The startle reflex is just one of many fascinating reflexes your newborn is born with, and watching these automatic responses gradually give way to purposeful movements is one of the many highlights of those early months.  

While the Moro reflex can sometimes disrupt sleep or cause momentary distress, it's temporary and a completely normal part of your baby's development. 

With a little understanding and some helpful strategies like swaddling, you can support your baby through this phase and help everyone get a bit more rest.