Baby Not Gaining Weight – Causes, Signs, & Remedies

All parents worry about their child’s development, a lot goes into ensuring the healthy growth of a child, steady and healthy weight gain is one of the most crucial aspects of this growth. Much like weight loss, weight gain can be a difficult and tedious process.

What is the Expected Weight Gain in Infants and Babies?

Early childhood malnutrition is one of the most severe and avoidable conditions any baby can face, knowing if your child is malnourished is the first step towards solving this problem. Using the W.H.O study on baby growth as a benchmark is the best way to understand what healthy and unhealthy weight gain is for a child.

According to the Australian breastfeeding association who use the same standards as W.H.O for baby growth, the normal standards for weight loss and weight gain for babies are:

  • A newborn loses approximately 5% to 10% of their birth weight within the first week after the delivery.
  • A newborn begins to put on the lost weight within the first three weeks of delivery.
  • Natural weight gain for babies should double their birth weight within the first three to four months after birth.
  • Boys can gain almost three times their birth weight within the first year.
  • Girls can take up to sixteen months to triple their birth weight.
  • Within the first year, your baby’s birth length is expected to increase one and a half times.
  • Your baby’s head circumference is expected to increase by almost 11 inches before or around their first birthday.

Note: These are guidelines based on a UN study, if your baby does not meet these standards, please contact your doctor for a better understanding of whether your baby is developing naturally.

Do you Need to Worry if your Baby is Failing to Gain Weight?

It is important to remember that your baby is unique; no two infants are born the same. At times a child can have a slower rate of growth. Be sure to watch your baby’s weight, however, as an extremely slow pace of growth can be a worrying sign. Talk to your paediatric specialist, follow a healthy nutritious diet and remember to not panic and over-feed your child. Inculcating healthy food habits from birth can go a long way in ensuring that your child always eats healthy.

Each child has a completely unique growth curve, as long as your doctors aren’t worried and your child is eating healthily, you can rest easy as that weight gain will occur based on their natural rate of growth. Slow weight gain in infants can be normal but should be monitored.

How is your Baby’s Weight Measured?

A baby on a weighing scale at the doctor's clinic

Using what is known as a developmental milestone, doctors can begin measuring the weight of your child and assess the expected weight gain or weight loss required for healthy development. These milestones can vary from baby to baby. They not only include weight and height but other factors like when your baby first smiles, and when they begin to turn their head to a sound, if they can roll to their tummy when on their back, when they lift their hands to their mouth, and if they can carry the weight of their neck without support.

The milestones are decided after your doctor gives your child a complete physical within the first two weeks, they also will ask you to keep an eye on certain developmental features like if they cry or if they make any sounds. Once the exam is complete the doctors will ask you some routine questions about the baby’s development to understand if there is a problem. If they identify a problem they will investigate through both questions and medical tests to find the underlying cause.

The difficulty with weight gain can be a common problem for children who are delivered prematurely. Although, a child who is carried to term faces less risk of weight fluctuations during infancy there is still a possibility of this occurring.

 Reasons for a Baby not Gaining Weight

Using the already mentioned technique to identify if your baby is growing naturally or not, the doctor will diagnose your child as either healthy or not. The criteria they will use to make a diagnosis are:

  • Dropping to the third percentile for weight on the growth chart the doctors have assigned to them.
  • Falling to an extremely low body mass index (BMI) which means they are below 20% of the weight they are supposed to be based on their height.
  • The baby drops more than two percentile lines on their assigned growth chart after their last check-up.

Under the circumstances these criteria all point to a problem in weight gain, the doctor will try to determine the cause of the lacklustre weight gain. Some of the causes of slow weight gain in babies are:

  • Problems With The Feeding – The most common reason for your baby’s lack of weight gain is that they are not feeding sufficiently or are not getting enough milk during a feed. This could be due to numerous reasons like the baby is tongue tied or the mother has problems producing enough milk. Talking to a lactation specialist can help improve the quality of each feeding session for your baby, before doing this, however, consult your doctor or lactation specialist to identify the reason for either low supply of breastmilk or the medical condition your child may have that is causing them to struggle with their feeding.
  • Pre-existing Medical Conditions – The reason for your baby not gaining weight could also be due to another pre-existing condition, as mentioned in the point above, your baby being tongue tied could be one of those reasons. Another condition could be if the mother has an inverted nipple. There are numerous medical conditions that can afflict both the mother and child that could cause a poor feeding session, it is recommended that you talk to your doctor and go through a full set of tests as requested by them to better identify the medical condition either you or your child may face. Once identified the doctor will help create a treatment plan to help improve the feeding cycles.

Signs and Symptoms of Baby not Gaining Weight

The only way to know if your baby is not gaining enough weight is through regular weigh-ins and check-ups. It is also recommended that you monitor their stools, urine and feeding habits and make a note of them. If there are any irregularities, it is advisable to consult your physician.

One of the biggest signs of slowed weight gain is if your baby is ill. If they show flu-like symptoms you may need to increase your feeding time or add an extra session. This is because they do not get enough nutrients when sick to combat the illness and continue to gain weight.

Diagnosing Slow Weight Gain in Babies

Doctors can use numerous ways to diagnose delayed weight gain in babies. Some of the common ones are:

  • If your baby is in the bottom percentile of their growth chart. The WHO chart mentioned earlier shows a graph that indicates percentiles and centiles. If your baby is in the bottom 3% this means out of 100 babies only 3 would be either smaller than or the size of your baby. This is the fastest way to diagnose slowed weight gain in babies.
  • If your baby does not weigh more between check-ups or their bi-weekly weigh-ins, they may be malnourished.
  • Blood tests can indicate if there is a medical reason for the slowed weight gain. Doctors often apply a wait and watch approach before suggesting this method of diagnosis. The kind of blood test depends on the symptoms your child shows and is determined on a case by case basis.
  • Doctors may question you about your family history to investigate if there maybe an underlying genetic condition they need to test for that is responsible for the slow weight gain.

Complications of Poor Weight Gain in Babies

If left unmonitored or unmanaged poor weight gain in infants can cause complications like:

  • Heart problems
  • Growth instability
  • Malnutrition
  • Weakened immune systems
  • Weak muscle structure
  • Lack of energy
  • A fever

What can you do to Increase your Baby’s Weight?

Increasing your baby’s weight should be done slowly and in a sustained manner. Here are a few things you can do to help your baby gain the right kind of weight.


There are numerous treatment methods to help improve your baby’s weight, some of the more common ones are:

  • Using a nipple shield to help with the feeding.
  • External feeding through a dropper or bottle.
  • Medication may be prescribed by gastroenterologists
  • Supplements may be prescribed through dieticians

Home Remedies

Sometimes taking a wait-and-watch approach may be best for the baby’s weight gain. The doctor may however, feel your baby needs to gain weight quicker but may not recommend medication. The best form of home remedy would be increasing the number of times you feed your baby or the time you take to feed your baby.

Does slow Weight Gain affect your Baby’s Health in the Long-term?

If left untreated, slow weight gain could cause major complications as mentioned earlier. It is recommended that you talk to your doctor to see if your baby is malnourished and if they recommend any treatment. There is, however, no need to panic as there are numerous ways to combat the poor weight gain in infants that have been mentioned above. Talk to your doctor for more techniques and treatments to help your child get the right kind of nourishment.

Is your baby getting enough Nutrition through Breastfeeding?

A mother breastfeeding her infant

In the first 3 months, if your child is being breastfed exclusively, there are some signs that can help you identify if the baby is not gaining weight on breastmilk:

  • You need to change their disposable diapers 5-6 times in a single day.
  • If using cloth diapers, you may need to change their diapers 7-8 times a day.
  • They may be struggling to suckle on your breast and may be moving their jaws more than normal, making a sucking noise or sometimes even hear him swallowing loudly.
  • If the breasts do not feel as tender and feel softer than they did before it might be an indication that the baby is not able to grip the breast, this is a sign the baby isn’t feeding as well as before.
  • If at regular weigh-ins his weight stalls or stops growing after the first three months, it is a sign of bad nutrition.

When to Seek Medical Advice?

It is recommended that you seek medical advice as soon as possible regarding your child’s weight disabilities as they could be a sign of further complications. Do not panic, as in most cases weight gain or loss for infants can be managed with nutritional and routine changes.

Weight gain can be a problem both ways, a child can be gaining too much weight or they could be struggling to gain weight. This can be irrespective of the kind of diet you feed your child. The unnatural development of a baby’s weight is something every parent should watch out for.

Also Read:

Newborn Baby Weight Gain – What’s Normal and What’s Not
Baby Boy Height & Weight Growth Chart: 0 to 12 Months