Shaken baby syndrome

Shaken baby syndrome is the collection of signs and symptoms resulting from the violent shaking of an infant or small child. Shaken baby syndrome is a form of child abuse and the consequence of an assault, not the result of active play or clumsy handling. Shaken baby syndrome is the leading cause of death in child abuse cases in the U.S.

Each year, at least three children in Arizona will die from injuries related to shaken baby syndrome. The average age of the child affected by the syndrome is between 3 and 8 months. However, more than half of the children abused are 6 months of age or younger. One-fourth to one-third of these victims will die; the rest will suffer lifelong complications.

Shaken baby syndrome occurs when an infant or small child is shaken forcefully and/or if the head is hit hard against an object such as a mattress, floor or wall. A baby's head makes up approximately 25% of his/her total body weight. Babies' heads are large and heavy relative to their bodies, and their neck muscles are weak. In addition, the blood vessels surrounding the brains of infants and children under the age of five are more susceptible to tearing than those of older children and adults.

The forceful motion of the head hitting an object or snapping back and forth causes the fragile and immature brain of the child to slam against the skull. This trauma results in the ripping and tearing of blood vessels in the brain and eyes. The bleeding around the brain may lead to blood pooling within the skull, causing swelling, increased pressure and further damage to the brain.

It only takes seconds of shaking to cause irreversible brain damage in an infant.

Signs and symptoms of shaken baby syndrome

Shaken baby syndrome has several signs and symptoms. Severe cases typically exhibit obvious symptoms and often result in critical neurological consequences or death. Signs and symptoms of shaken baby syndrome include:

  • Lethargy/decreased muscle tone
  • Extreme irritability
  • Decreased appetite, poor feeding or vomiting for no apparent reason
  • No reaction to sounds or acting lifeless
  • No smiling or vocalization
  • Poor sucking or swallowing
  • Inability to lift head
  • Inability of eyes to focus or track movement or unequal size of pupils
  • Head or forehead appears larger than usual or a soft spot on the head appears to be bulging
  • Rigidity or posturing
  • Seizures
  • Irregular, difficult or lack of breathing

Less severe cases may not show immediate symptoms or noticeable injury and, therefore, may not be brought to the attention of medical professionals. Although these cases may never be diagnosed or reported, they're still capable of causing long-term damage or consequences. Possible long-term effects include:

  • Physical and learning disabilities
  • Visual impairment or blindness
  • Hearing impairment
  • Speech disabilities
  • Cerebral palsy
  • Seizures
  • Behavioral disorders
  • Death

Most incidences of shaken baby syndrome occur when a baby will not stop crying. It's not unusual for parents and caregivers to experience periods of exhaustion and frustration, especially if they're unable to calm a crying child. An extremely fussy baby, long periods of inconsolable crying, or issues related to feeding or toileting may generate stress in the parent or caregiver. As a result, violent reactions may be triggered, and a child may be shaken out of frustration or anger.

Regardless of the state of aggravation, it is never acceptable to shake a baby or young child.

If you ever feel you can no longer appropriately handle your baby's crying and you have met the baby's basic needs, such as feeding, clean diapers, appropriate clothing and gentle holding of the baby, please stop and take a break. Here's a list of things to think about and do if you're afraid you have become too frustrated:

  • Take a deep breath
  • Close your eyes and count to 10…slowly
  • Place your baby on his/her back in a safe place (crib, bassinet, etc.), close the door and go to another room
  • Check on your baby every five to 10 minutes
  • Call a trusted friend, family member or neighbor and talk about your frustration
  • If possible, ask a trusted friend, family member or neighbor to take over for a little while
  • Allow yourself time to decompress. Listen to music, watch TV, exercise or just relax
  • Watch this video on YouTube: Never shake a baby
  • Do not pick up your baby again until you're feeling calm
  • If you suspect that your baby is ill, contact your healthcare provider immediately or take your baby to the hospital

Finally, remind your child's caregivers that it is NEVER okay to shake a baby or child. If you suspect or know that a child has been shaken, seek medical attention immediately. Do not let fear, shame or embarrassment keep you from doing the right thing. It's crucial that the infant or child receive the necessary and proper treatment without delay.

For more information regarding shaken baby syndrome, visit

Sources: The National Coalition on Shaken Baby Syndrome and Never Shake a Baby Arizona.

Download the printable version of this page (PDF)