Babies & Restless Arms

As your baby gets older, you might be surprised to see her in constant motion, even before she can roll over or crawl. Babies learn about the world around them by moving their body and interacting with their environment.

Your baby's arm movements can tell you important things about what she is experiencing. Once you know why your baby might have restless arms, you can rest assured that she is most likely learning about and interacting with the world around her.

Startle Reflex

Young infants have a startle reflex, called the Moro reflex, that causes sharp arm and leg movements.

If your baby hears a loud noise, her arms might instinctively extend out and then slowly lower back toward her body. The sound of her own crying might also cause the startle reflex. Sudden movements, such as shifting her car seat while she is sleeping, might also cause her arms to reflexively extend from her body.


baby laying down

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You might notice your baby constantly waving her arms while she is awake, particularly if she is looking at something interesting.

When your baby waves her arms, she is likely excited or interested in what she is seeing. She might wave her arms when you talk to her, show her things or when she tries to grasp a toy or other object.

Until your baby is 2 or 3 months old, her waving arms are not controlled or purposeful. Once she gets older, waving her arms will be more purposeful as she tries to grab what she is looking at.

Increasing Motor Skills

Moving is how your baby increases her muscle strength to improve her motor skills. You might notice your baby putting her hands in her mouth, opening and closing her hands and waving toys around wildly. Each of these movements can appear restless but are helping your baby develop the skills necessary to begin rolling over and sitting up. Let your baby lie on her tummy for short periods during the day to encourage her to move her arms around so can build these skills.


baby laying down

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If your baby does not move her arms around at all, speak with her pediatrician. Your little one should reach certain developmental milestones by the time she reaches 3 months of age, such as opening and closing her hands and grasping objects. If she cannot do these things, she might have a developmental delay that needs immediate attention. If you find that your baby's restless arms keep her awake during naps and throughout the night, try swaddling her tightly to keep her arms still. Otherwise, encourage your baby's restless arms because she is interacting with and learning about her environment.