Erb’s palsy happens when a baby’s neck is stretched during labor and delivery. This can cause damage to the upper nerves of the neck and shoulder. The nerve damage can then cause certain muscles in the baby’s arm to be weak.

Vaginal Birth
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Erb’s palsy is usually caused by:

  • Long, difficult delivery
  • Delivery of a large baby
  • Shoulder dystocia
  • Breech delivery
  • Inability of your baby to move an arm or shoulder
  • Arm is bent inward toward the body
  • Weak or absent reflexes in the arm
  • Loss of feeling in the arm