Why Is My Baby Not Gaining Weight?

Why Your Baby May Not Be Gaining Weight as Expected

If your baby hasn't gained as much weight as expected, it's natural to feel concerned. The first step is to determine whether there’s an underlying issue or if it's just a false alarm due to unrealistic expectations.

Is it a Real Concern?

When a baby isn’t gaining weight as expected, it’s easy to become anxious. However, in some cases, the baby may be growing at a normal rate, and the concern is a misunderstanding. In other instances, there may indeed be a legitimate issue at hand. The key is to first rule out whether there is a real cause for concern by observing the signs of potential poor growth.

Recognizing the Signs of Poor Growth In Babies

Poor growth occurs when a baby doesn’t get enough calories to meet their genetic growth potential. Keep an eye out for these signs:

Failure to gain enough weight or weight loss: Growth may slow or stop suddenly or gradually. A baby who doesn’t gain weight appropriately may be classified as “failure to thrive.”
Weight significantly lower than length on growth charts: A noticeable gap between weight and length could indicate growth issues.
Less than 5 wet diapers a day: This may suggest that your baby isn’t getting enough fluids.
Infrequent bowel movements: Low milk intake can lead to fewer bowel movements.
Irritability and sleep disturbances: Hunger can cause discomfort and poor sleep.
Lethargy and excessive sleep: Weak or malnourished babies may sleep more than usual.

These signs could indicate inadequate milk or food intake, but it’s essential to assess the situation carefully. If these signs don’t seem to align, check out “Growth False Alarms” for other possible causes.

Possible Causes of Poor Weight Gain

Poor growth in babies can generally fall into two broad categories:

Organic causes: An underlying physical issue, illness, or medical condition.
Non-organic causes: Behavioral or social factors that affect feeding.

Most cases of “failure to thrive” (over 80%) are due to non-organic causes, while physical or medical issues contribute to the remaining cases.

Behavioral & Social Causes

Poor weight gain from behavioral and social factors typically involves insufficient calorie intake. Some reasons for this could include:

Baby isn’t offered enough calories: This can occur due to insufficient milk supply, rigid feeding schedules, or neglect.
Baby can’t consume enough calories: Even with sufficient milk, the baby might not be able to feed effectively due to poor latch or positioning issues.
Baby refuses to consume enough: Babies may actively refuse feeding or may not be interested due to stress, breast refusal, or starting solids too early.

For Breastfed Babies:

Not offered enough milk: Possible reasons include low milk supply, irregular feeding schedules, or neglect.
Can’t access enough milk: This can be due to poor latch, improper positioning, or sleep deprivation.
Won’t feed enough: This could be due to breastfeeding strikes, early introduction of solids, or stress.

For Bottle-Fed Babies:

Not offered enough milk: This can occur from incorrect formula preparation or neglect.
Can’t drink enough milk: Issues may stem from faulty equipment or poor feeding techniques.
Won’t drink enough: Refusal could happen due to solids given before milk, feeding aversion, or stress.

Solids and Their Role In Poor Weight Gain:

Not enough solids: Some babies older than 7 months may not be offered solids or may face restrictions.
Too many solids: Solid foods may be filling the baby but not providing adequate nutrients, leaving them unwilling to drink enough milk.
Unsuitable food choices: Offering too many unsuitable foods or juices can cause malabsorption issues.

Be aware that these factors can often overlap, and each baby may have different reasons for poor growth.

Physical & Medical Causes

In some cases, the reason for poor growth is due to physical or medical conditions. Although most of these problems can be identified soon after birth, some may not become apparent until months later. Here are some potential causes:

Baby isn’t able to drink or eat enough: Conditions like prematurity, neurological issues, or tongue tie can interfere with feeding from birth.
Baby isn’t willing to eat or drink enough: This could be due to illness, infections, anemia, or feeding aversions caused by discomfort.
Baby can’t digest or absorb enough: Conditions like pyloric stenosis, gastrointestinal infections, or allergies may prevent proper digestion or absorption.
High energy requirements: Some health conditions, such as cardiac or chronic lung issues, can increase a baby’s caloric needs.
Growth hormone deficiencies: Babies with growth hormone issues often show poor growth from birth.

When to Seek Medical Advice

If your baby’s weight gain remains a concern, it’s important to see a pediatrician to rule out any medical conditions. If your baby is already receiving treatment but growth continues to be slow, consider the possibility of an additional behavioral factor. In some cases, a combination of medical and behavioral factors might be at play.

By recognizing the signs and understanding the causes of poor weight gain, you can better support your baby’s growth and development. If you’re still worried about your baby’s health or growth, seeking professional advice from a pediatrician is always the best course of action.