Babies may experience difficulty moving their head from side to side or lifting it up while lying on their back, being held, or lying on their tummy. ^2,5 They might rest their head on one side with little movement.

Watch the video to see how a doctor will check for a baby's head control.

Babies may exhibit limited arm and leg movement while lying on their back, such as rarely kicking their legs or moving their arms away from their body. They may also struggle to lift their arms and legs, appear floppy or weak, and have legs in a 'frog leg' position. Parents or caregivers may also notice that their baby's limbs feel limp when held.^3,6

Parents or caregivers may observe that their baby's breathing is rapid even at rest, and lacks deep breaths in or out. The baby's chest may appear bell-shaped, and their belly may move more noticeably than their chest while breathing.³ This is most easily seen when the baby is lying on their back without clothes on the upper half of their body.

Due to muscle weakness, babies may experience difficulty sucking or swallowing during feeding,^3,4 which may lead to choking and make weight gain challenging.⁵ Parents or caregivers may also notice slow feeding as the baby struggles to swallow.⁵
 

Parents or caregivers may notice that their baby's cry sounds weak and difficult to hear. Babies with weakness may also experience difficulty coughing and clearing mucus from their chest, resulting in weak coughs and chest sounding congested.⁵