When a newborn does not gain weight as expected, it is a significant concern for parents. This article explores common reasons for slow weight gain and outlines appropriate steps to take.
Understanding Typical Newborn Weight Gain
Newborns typically experience a physiological weight loss during their first few days, a normal adjustment outside the womb. This initial decrease is usually 5% to 7% of their birth weight for formula-fed newborns, and up to 7% to 10% for breastfed babies. Most healthy newborns regain their birth weight by 10 to 14 days of age. If a baby loses more than 10% of their birth weight or has not returned to it by three weeks, medical attention may be needed.
After regaining birth weight, infants begin a period of steady growth. During the first few months, a healthy full-term newborn typically gains about 0.5 to 1 ounce (15 to 30 grams) per day, or 5 to 7 ounces (140 to 200 grams) per week. This translates to approximately 1 to 2 pounds per month. While these are general guidelines, each baby grows at their own pace, and individual variations are common.
Common Feeding-Related Issues
Many instances of slow weight gain in newborns are linked to feeding practices, encompassing both breastfeeding and formula feeding. For breastfed infants, an improper latch is a frequent cause of insufficient milk transfer, meaning the baby is not effectively removing milk from the breast even if the mother has an adequate supply. This can lead to the baby not receiving enough calories despite spending time at the breast. Infrequent feedings, where a baby is not fed often enough throughout the day, can also limit overall milk intake.
Insufficient milk transfer can also occur due to issues like a weak suck from the baby or conditions such as tongue-tie (ankyloglossia) or lip-tie, which restrict the baby’s ability to latch deeply and effectively extract milk.
Certain maternal health conditions can also impact milk supply. For example, retained placental fragments can suppress prolactin, delaying milk production. Additionally, some medications, such as decongestants, certain antihistamines, or high doses of steroids, can decrease milk supply.
For formula-fed babies, improper preparation of formula is a common issue; diluting formula with too much water can significantly reduce its caloric density, thereby limiting the baby’s nutritional intake. Similarly, if the volume of formula offered is consistently less than the baby needs, or if bottle mechanics, such as a nipple flow that is too slow, hinder efficient feeding, the baby may not consume enough. Some newborns are excessively sleepy, leading to missed feedings or short, ineffective feeding sessions, while others may have a weak suck reflex that prevents them from taking in sufficient nourishment.
Other Underlying Factors
Beyond feeding challenges, other less common factors can contribute to a newborn’s slow weight gain. Infections, even minor ones, can increase a baby’s metabolic demands, causing them to burn more calories than they consume for growth. Certain metabolic disorders, although rare, can interfere with the body’s ability to process nutrients and convert them into energy for growth.
Congenital heart defects can also impact weight gain, as the heart may have to work harder to pump blood, increasing caloric expenditure. Digestive issues, such as severe gastroesophageal reflux disease, can lead to frequent spitting up and a reluctance to feed, limiting nutrient absorption.
Conditions like malabsorption syndromes, where the intestines struggle to absorb nutrients from food, also prevent adequate caloric intake. Environmental factors, such as keeping a baby in a very cold room, can force their body to expend extra energy to maintain warmth, diverting calories away from growth.
Seeking Professional Guidance
It is important to contact a healthcare provider if parents observe specific signs indicating a newborn’s weight gain is a concern. These signs include persistent fussiness or irritability, unusual lethargy, or a significant decrease in the number of wet or dirty diapers. Continued lack of weight gain or further weight loss despite adjustments to feeding practices also warrants immediate medical attention.
During a medical evaluation, the healthcare provider will discuss the baby’s detailed feeding history, including frequency, duration, and any observed difficulties. A thorough physical examination will assess the baby’s overall health and identify any potential underlying medical conditions. Specific tests, such as blood tests or imaging studies, might be indicated. The goal is to develop a feeding plan and address any identified issues. Early assessment and intervention can prevent serious health complications and support the baby’s healthy development.