What's Fencing Reflex and Why Do Newborns Do It?

Ever wonder why your little one is posing like a fencer?

newborn baby
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As you watch your newborn develop, it's important to know about all of the involuntary movements babies exhibit, including the fencing reflex. This motion causes babies to assume the "fencing position" when placed on their backs. Learn more about why babies have this reflex.

Test Out the Fencing Reflex 

If you place your baby on his back, his head will turn with the arm and leg of one side extended (the pair on the side he’s turned toward) and his other arm and leg will be flexed.

This reflex can be present about the time your baby begins rolling over (back-to-stomach) competently and regularly. It’s thought that this reflex helps prevent a baby from rolling over onto his stomach before his brain and body are ready. This is another good reason why putting your baby on his back to sleep is important.

Other Names for the Fencing Reflex

The fencing reflex is also called Tonic Neck Reflex; though your partner might think it’s very funny and call it Captain Morgan’s Reflex. This involuntary movement will gradually disappear between age 3 and 6 months. 

This reflex is an important sign of your baby's nervous system development and function. If your baby never exhibits this reflex, talk to your health care provider at the next check-up. Sometimes a trained eye can help you spot this one a little better. If, on the other hand, your baby is in this position the majority of the time, contact your health care provider immediately as it could be a sign of a larger neurological problem.

Types of Newborn Reflexes

Read about other involuntary motions vital to your little one's healthy development. Most reflexes will disappear between 3 and 6 months of age. 

  • Palmar grasp: If you touch the palm of your baby's hand, his fingers will automatically curl around and cling to your finger. In other words, your newborn will "hold"your hand. 
  • Plantar grasp (or Babinski reflex): Stroke the sole of your baby's foot and watch his toes spread open and his foot turn slightly inward. 
  • Moro reflex (or startle reflex): This reflex is why your little one reacts to a loud noise. He will involuntarily extend his arms, legs and fingers and arc
  • Sucking reflex: Your baby will automatically begin sucking if you touch the roof of his mouth with your finger, a pacifier or a nipple. 
  • Rooting reflex: This reflex helps your little one locate the breast or bottle to begin feeding. Try it: Stroke your newborn's cheek, he'll automatically open his mouth and turn his head toward the side that was stroked. 
  • Stepping reflex: Your newborn will look like he's "walking," placing one foot in front of the other when you place his feet on a flat surface.

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