Newborn Reflexes - Complete Guide to Primitive Reflexes 2026

 

Published - February 6 Last Updated: February 6, 2026

At my daughter's 2-week checkup, the pediatrician suddenly clapped her hands loudly near the exam table. My daughter's arms shot out wide, then slowly came back in, as if she were hugging herself. That’s an excellent display of the Moro reflex,” the doctor commented warmly, his smile reassuring. I had no idea what that meant. Here's everything I learned about newborn reflexes, those fascinating automatic responses that reveal how your baby's nervous system is developing.


Newborn Reflexes



What Are Newborn Reflexes?

Involuntary Responses

Newborn reflexes are automatic movements that happen without your baby thinking about them. Touch your baby's cheek, and they turn toward your finger. They're not choosing to do this—their nervous system does it automatically.

These aren't random movements. They're built-in survival tools that help babies eat, protect themselves, and interact with the world before their brains can control movements intentionally.

Why Babies Have These Reflexes

Think of reflexes as your baby's first instruction manual. The rooting reflex helps them find food. The sucking reflex helps them eat. The grasp reflex helped our ancestors' babies hold on to their mothers.

These reflexes are hard-wired from millions of years of evolution. They keep babies safe and help them survive in those early weeks when they can't do much else.

When Reflexes Go Away

Most newborn reflexes fade between 3 and 6 months. This is news—it means your baby's brain is developing voluntary control.

When reflexes disappear, they're replaced by intentional movements. The stepping reflex vanishes around 2 months, but real walking starts around 9-15 months. Different parts of the brain control each action.

The Moro Reflex (Startle Reflex)

What It Looks Like

The Moro reflex is impossible to miss. Your baby's arms fly out to the sides with palms up and fingers spread. Then the arms come back in like they're hugging themselves. Often, the baby cries too.

It looks like your baby is saying "Whoa!" and trying to grab something.

What Triggers It

Several things set off the Moro reflex -

  • Suddenly loud noises
  • Quick position changes
  • Feeling unsupported (like when you lower them into the crib)
  • Bright lights
  • Their own sudden movements

Sometimes it happens for no simple reason during sleep. This is normal.

Why It Affects Sleep

The Moro reflex is a major sleep problem for newborns. Baby is sleeping peacefully, moves a tiny bit, triggers their own startle reflex, and wakes themselves up.

The startle reflex affecting sleep is why many babies wake themselves up—swaddling helps contain this response.

This is why swaddling works so well. It gently keeps the arms contained so the startle response doesn't fully activate.

Important note - The Moro reflex typically disappears between 3 and 6 months. If it's still strong after 6 months or completely absent at birth, tell your pediatrician.

Rooting and Sucking Reflexes

How They Work Together

Stroke your baby's cheek or mouth, and they'll turn their head toward your touch with their mouth open. This is the rooting reflex—nature's GPS for finding food.

Once something touches their mouth—nipple, finger, pacifier—they automatically start sucking. This powerful combo ensures babies can eat from day one.

Why They Matter for Feeding

These reflexes make feeding possible before babies have any voluntary control. Rooting helps them find a food source. Sucking helps them extract and swallow milk.

Even premature babies often have strong sucking reflexes, which help them feed despite being born early.

When They Fade

The rooting reflex usually disappears around 4 months, though some babies keep it longer. By the age of 2 to 4 months, the automatic sucking reflex gradually develops into a deliberate, voluntary action.

By then, babies can intentionally put things in their mouths and choose whether to suck. It's no longer purely automatic.

Grasp Reflexes

Palmar Grasp (Hand)

Place your finger in your newborn's palm. Their tiny hands will close around it with surprising strength. This is the palmar grasp reflex.

Some newborns grip so tightly they could briefly support their own weight if lifted. Never test this on purpose; it's not safe. But it shows how strong this reflex is.

Plantar Grasp (Foot)

Press gently on the ball of your baby's foot. Their toes curl downward, trying to grip.

This is less noticeable than hand grasping, but it serves the same evolutionary purpose. Our ancestors' babies needed to grip with both hands and feet to stay safe.

When Voluntary Grasping Starts

The palmar grasp reflex fades around 5-6 months. It's replaced by voluntary, purposeful grasping.

You'll notice the difference easily. Reflex grasping is automatic and releases when you pull away. Voluntary grasping is intentional—the baby reaches for what they want and can choose to let go.

Other Important Newborn Reflexes

Tonic Neck Reflex (Fencing Position)

When your baby's head turns to one side, the arm on that side extends while the opposite arm bends. This creates a "fencing" position.

It's most obvious when a baby lies on its back. This reflex appears at birth and fades by 5-7 months.

When worrying - If your baby seems stuck in this position constantly or displays it rigidly, tell your pediatrician.

Stepping Reflex

Keep your baby in an upright position, allowing their feet to gently press against a flat surface. They'll make stepping motions like they're walking.

It's purely reflexive, not intentional. This reflex disappears around 2 months, then real voluntary walking starts around 9-15 months, using completely different brain pathways.

Babinski Reflex (Toe Fanning)

Gently run your hand along the bottom of your baby’s foot, starting at the heel and moving toward the toes. Their toes fan out, and the big toes extend upward.

This is completely normal in babies and disappears between 12 and 24 months. In adults, this same response means neurological problems—but in babies, it's expected and healthy.

Protective Reflexes That Stay

Some reflexes never go away because we always need them:

  • Blinking when something comes toward the eyes
  • Gagging to prevent choking

These protective mechanisms stay with us for life.

How Doctors Test Newborn Reflexes

What Happens with Checkups

Reflexes tested at birth are part of the initial Apgar assessment and newborn examination. Doctors test reflexes at birth as part of the initial examination.

At later checkups, your pediatrician will test various reflexes to check neurological development. Checking reflexes during routine visits is a standard part of developmental screening throughout a baby’s first year.

Why Testing Matters

Reflex testing gives doctors a window into your baby's nervous system. Proper reflexes show healthy brain and nerve development.

Absent, weak, asymmetric, or persistent reflexes can signal problems that need more evaluation.

What Normal Looks Like

Normal reflexes are -

  • Symmetrical (same on both sides)
  • Appropriate strength (not absent, not too strong)
  • Age-appropriate (present when expected, fading on schedule)
  • Consistent (reliable when tested properly)

Your pediatrician knows what to look for and can tell normal variation from concerning patterns.

When Reflexes Signal Problems

Warning Signs to Watch For

Contact your pediatrician if you notice:

Absent reflexes - If a reflex that should be there is completely missing, like no Moro reflex at birth or no sucking reflex.

Asymmetric reflexes - If reflexes are strong on one side but weak or absent on the other. This could mean nerve damage from birth or other neurological concerns.

Reflexes that don't fade - If primitive reflexes persist beyond 6-7 months. A Moro reflex still present at 8 months needs evaluation.

Feeble or strong responses - Reflexes should be present but not exaggerated.

Absent or persistent reflexes are developmental concerns requiring evaluation by a pediatrician or specialist.

Supporting Healthy Development of Newborn Reflexes

What You Can Do

You can't make reflexes integrate faster, but you can support healthy development:

Daily tummy time - Strengthens muscles and promotes motor development. Start from birth with brief sessions. Tummy time and reflex integration work together—prone positioning helps primitive reflexes fade as voluntary control emerges.

Responsive interaction - Talk to your baby, make eye contact, and respond to their sounds. This stimulates brain development.

Safe exploration: Let the baby practice emerging voluntary movements in a safe environment.

Regular checkups - Ensure development is progressing as expected.

How Reflexes Fade Naturally

Reflexes don't vanish suddenly. They gradually integrate as your baby's brain develops higher-level control.

You'll notice reflexes becoming less obvious before they disappear completely. Reflexive grasping becomes intentional reaching. Random movements become purposeful actions.

As reflexes integrate, babies reach developmental milestones, and reflex integration marks neurological maturation. This transition shows your baby's brain is developing beautifully. It's not a loss—it's progress.

Quick Reference Guide to Common Reflexes

Moro (Startle) Reflex - Arms fly out, then come back in. Disappears at 3-6 months.

Rooting Reflex - Turns toward touch on the cheek. Disappears around 4 months.

Sucking Reflex - Automatic sucking on anything in the mouth. Becomes voluntary at 2-4 months.

Palmar Grasp - Hand closes around a finger. Disappears at 5-6 months.

Stepping Reflex - Makes walking motions when held upright. Disappears around 2 months.

Babinski Reflex: When the sole is stroked, the toes spread outward. Disappears at 12-24 months.

Frequently Asked Questions

Why does my baby throw their arms out suddenly while sleeping?

That's the Moro (startle) reflex. It's triggered by feeling unsupported or sudden position changes. Swaddling helps contain this reflex, so the baby doesn't wake themselves. It disappears around 3-6 months.

When should I worry about my baby's reflexes?

Concerning signs include reflexes absent at birth, reflexes only on one side of the body, reflexes that don't fade by 6 months, or feeble responses. Discuss with your pediatrician if you notice these.

Why does my baby make stepping motions when I hold them upright?

That's the stepping reflex—an automatic response when feet touch a surface. It disappears around 2 months, then reappears as voluntary walking around 9-15 months. The reflex and voluntary walking use different parts of the brain.

Is it normal for my baby's toes to fan out?

Yes! The Babinski reflex (toes fanning when the foot sole is stroked) is normal in babies. It disappears around 12-24 months. In adults, this response means neurological problems, but in babies, it's expected.

Can I test my baby's reflexes at home?

You can observe them naturally (like rooting when the cheek is touched, grasping your finger), but don't deliberately trigger the Moro reflex repeatedly; it's stressful for the baby. Let your pediatrician perform formal reflex testing.

Final Thoughts

Understanding newborn reflexes helps you appreciate how incredibly prepared your baby is for life outside the womb. These automatic responses aren't random—they're survival tools refined over millions of years of human evolution.

As your baby grows, you'll watch these reflexes gradually fade and transform into purposeful, controlled movements. That tight newborn grasp becomes an intentional reach for a toy. Those automatic stepping motions become real first steps.

Remember - Every baby develops at their own pace. Some reflexes may fade a bit earlier or later than the typical timeframe, and that's usually perfectly normal. Your pediatrician will monitor reflex development at each checkup and let you know if anything needs attention.

The most important thing? Enjoy watching your baby's nervous system develop right before your eyes. These reflexes are just the beginning of an amazing developmental journey.

If you ever have concerns about your baby's reflexes or development, don't hesitate to ask your pediatrician. Trust your instincts; you know your baby best.

Reflexes are one fascinating aspect of newborn development—explore our complete newborn health guide for all developmental topics.

Want to track all developmental milestones? Read our complete guide to newborn development from birth to 3 months.

Medical Disclaimer: This article provides general information and is not a substitute for professional medical advice. Discuss your baby's reflexes and development with your pediatrician.

Reference

  1. American Academy of Pediatrics - https://www.healthychildren.org/English/ages-stages/baby/Pages/Newborn-Reflexes.aspx
  2. National Institutes of Health - https://medlineplus.gov/ency/article/003292.htm

 

 

Adelgalal775
Adelgalal775
I am 58, a dedicated father, grandfather, and the creator of a comprehensive parenting blog. parnthub.com With a wealth of personal experience and a passion for sharing valuable parenting insights, Adel has established an informative online platform to support and guide parents through various stages of child-rearing.
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