Overview Feeding is hard work for an infant, who needs to coordinate sucking, swallowing and breathing all at the same time. Feeding fatigue can be a serious symptom in an infant, who may not be getting the nutrition he needs if he tires before the end of a meal. If you think your baby is tiring before he finishes his feeding, talk to your doctor. Prematurity A premature baby often doesn't have the muscle development to coordinate sucking and swallowing long enough to consume the calories he needs. Because a preemie tires easily, he may need all of part of his meal given through a feeding tube. As he grows and develops the ability to suck and swallow at the same time for longer periods, oral feedings can increase. Most babies develop this ability around 32 to 34 weeks gestational age, according to West Penn Allegheny Women's and Infant's Services. Heart and lung conditions Around 1 in 100 babies have a heart defect, according to KidsHealth, but not all experience feeding difficulties. A baby with a heart condition may tire easily during feedings because her heart has to pump harder during feedings. She may also develop a bluish tinge around her mouth or on her hands and feet due to lack of oxygen when she eats. Respiratory conditions, whether congenital or acquired after birth, can also result in feeding fatigue in an infant, who has more difficulty maintaining adequate oxygen levels when eating. Muscle weakness Babies with genetic abnormalities such as Down syndrome or genetic muscle disorders may have weak muscles overall, a condition known as hypotonia. Weakened muscles can affect not only the baby's physical development but also her ability to suck and swallow. An infant with cerebral palsy may have muscles that are either too floppy or too tight to allow her to eat effectively, which can lead to fatigue before the end of a meal. A majority of babies with cerebral palsy experience feeding difficulties, reports Dr. Joan C. Arvedson, director of the feeding clinic at the University of Wisconsin. Mechanical difficulties A baby with a cleft palate or other facial malformations such as Pierre Robin syndrome may also have trouble eating because the opening in the palate interferes with the suction the baby needs to draw milk from the nipple. Milk may come out the baby's nose while he feeds. Cleft palate babies may eat more slowly, which can tire them out before the end of the meal. Although cleft palate is generally diagnosed at birth, other abnormalities of the gastrointestinal tract may not be readily apparent at birth.