Poor Weight Gain in Infants

Most infants double their birth weight within four months and triple their birth weight before their first birthday, according to KidsHealth. However, some babies are slower to grow. This is sometimes called "failure to thrive."

Causes

• Failure to thrive can have several causes, such as gastrointestinal problems, heart or lung problems, endocrine system problems, chronic infections, cerebral palsy, blood disorders, metabolic disorders or poor nutrition. Doctors often cannot identify the cause of failure to thrive.

Feeding Infants

• Infants should breastfeed or consume infant formula several times a day for their first six months. Feed infants when they show signs of hunger, such as puckering their lips, opening their mouths or sticking out their tongues.

Warning

• Call your doctor if you are concerned about your infant's weight gain, or if your baby seems hungry, fussy and unsatisfied after feeding. Most babies spit up after eating, but regular vomiting may indicate a problem.