Why an Infant Won't Gain Weight

According to Dr. Alan Greene, infants typically double their birth weight between the ages of 4 and 6 months. However, some infants may be diagnosed with failure to thrive if they are not gaining weight at all or gaining very slowly.

Identification

• A baby's weight is analyzed using a growth chart, which indicates how a baby compares to all other babies at the same age. Data is reported in percentiles. A baby at the 50th percentile is average.

Significance

• A baby will be diagnosed with a condition called failure to thrive or failure to gain weight if he is at the 3rd percentile or below on the growth chart.

Types

• Failure to thrive can be caused by many different medical conditions. Testing will be required to determine the cause. Tests may include blood tests and urine tests. The condition can come from problems with the digestive system such as reflux or lactose intolerance or disease such as cystic fibrosis, celiac disease, endocrine disorder and heart disease.

Prevention/Solution

• Failure to thrive is usually treated with increasing the child's daily calorie intake and treating any underlying medical conditions.

Considerations

• A baby's weight may fluctuate and may even decrease when he is sick. Weight typically increases gradually over time. However, children with serious underlying medical conditions may always be smaller than average.