Baby, Pregnancy, and Parenting Information

The Newborn Startle Reflex

With the actual dictionary definition of ‘The reflex response of an infant in which the limb and neck muscles contract when the infant is allowed to drop a short distance or is startled by a sudden noise or jolt’ one might wonder if the startle reflex is dangerous for their infant. The answer is no.

newborn-startle-reflex.jpgInfants are born with this primitive reflex, also called the moro reflex, that helps them adapt and adjust to situations. You will often see a newborn jump when laid on a bed, even softly, showing that their muscles and reflexes are working properly. More common is having your baby startle when you start the vacuum cleaner in the room they are in, however not wake up. This is a good sign that your babies hearing is working up to par.

There are several things that may set your babies startle reflex off. They include but are definitely not limited too:

  • Running the vacuum
  • A telephone ringing
  • Being in car seat when it is places on the floor
  • Being touched while asleep
  • Other children screaming
  • Loud crowds
  • TV/Radio turning on/off

If you aren’t sure when your newborn is demonstrating the startle reflex, look for him to quickly extend his arms and legs, and lift his neck when asleep. This may or may not also be followed by a short cry, before he is quickly quiet and back to sleep.

Generally this reflex will be apparent at birth and will generally disappear by the time your newborn is 6 months old. It can often be seen in premature babies born after week 28, as one of their first infantile reflexes.

As always, if you are concerned about any movements your baby is making, go see your pediatrician. Likewise, if you are unsure that your baby has the startle reflex, as the pediatrician at your next visit.


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5 Responses to “The Newborn Startle Reflex”

  1. 5
    Carolyn Gregorio Says:

    This is to Jihane: my daughter is 7 wks and I noticed the same reflex patterns you mentioned. Did u find out more?

    Thank you,
    Carolyn

  2. 4
    Jihane Says:

    My son has 3 months and 20 days, he go through the same movements mentioned above but when there is no noise not asleep nothing just suddenly and 3 times consecutively. is that a normal startle reflex? or something dangerous??
    PLEASE HELP

  3. 3
    Einnob Says:

    My baby Was born at 27 weeks, she is now 32 weeks and still in the nicu. One of the nurses who looks after her seems to treat her roughly, she went into a cot today and the nurse didn’t put the cot on the elevated part properly and it dropped down with a big jolt. She also seemed to be scrubbing at her head after she had an ultra sound to get the gel off, right n the soft spot. Also tries to burp her and pats her back to hard for my liking. Am I being paranoid or should I say something?

  4. 2
    You Cried and We Listened « walkerbean Says:

    [...] a certain fold to wrap the baby up and restrict their arm movements, thereby limiting baby’s startle reflex. Evie loves the feeling of being wrapped and secure, and there’s the added bonus of the [...]

  5. 1
    From ‘Woombie’ To ‘Restra2′ In Gentle Stages | sparrow chat Says:

    [...] “The Newborn Startle Reflex” [...]

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