Baby Weight Loss After Birth: A Complete Guide

10 min read

Written by Bindu Raichura

Bindu Raichura

new born baby weight

After the baby is born, most parents’ first question will be how much weight the baby has? The health of the baby is generally examined by his/her weight. Parents often feel concerned about the baby’s weight loss after birth. The worst part is that most parents don’t know the causes of weight loss in babies after birth. This article outlines the answers to this weight loss.

Here are some of the general guidelines for parents to look at and measure the growth and weight of the baby. If your baby is not getting enough breastmilk, it is possible that they will lose a maximum of 10% of birth weight in the first week of life and will regain weight by the second week. However, not every baby grows in a similar way; they grow differently. Few changes can be seen in your baby after they are 2 or 5 days old. Weight and size is one such change. If you are concerned about weight loss in your baby, contact your doctor to get better medical advice.

In This Article

Average Newborn Baby Weight

Too low birth weight or too high birth weight may worry infant babies’ parents about obesity or malnutrition in the future. The average birth weight in babies is good as they remain safe from weight-related issues. The average newborn baby weight is around2.5 to 2.9 kgs. So, if your infant baby comes under this range of weight, then there is nothing to be worried about the baby’s size or weight.

How Much Weight Does A Baby Lose In The First Week?

As a concerned parent, it is normal to worry about weight loss in babies. In order to understand baby weight loss after birth, we first need to understand that baby’s weight is directly related to the mother’s breast milk. It means that once a mother’s breastfeeding is set in place, that is, between the 3rd and 5th day after they gave birth, then your baby will not lose any weight from there and will, in fact, start gaining weight.

  1. A newborn baby is generally expected to lose 5% to 10% of the weight in the first week of the birth, but will start gaining weight after the 2nd week of the birth.
  2. From the 3rd to the 5th day, their weight remains constant, and from the 5th day onwards, their weight grows as breastmilk increases.
  3. Babies in the first month after their birth continue to gain weight, around 30 grams per day. Most babies grow rapidly, i.e., when they are 7 to 10 days old.
  4. In the first month, the baby may gain weight up to 0.7 kilograms to 1.5 kilograms per month and will continue to gain for the first three months.

Other factors contributing to baby weight loss after birth are breast milk, sleep schedule, parental health, well-being, etc.

How Long do Babies Lose Weight After Birth?

newborn weight

As mentioned above, a newborn baby’s growth is entirely dependent on the mother’s breastfeeding milk. Once the breast milk sets in place and the milk supply increases, the newborn baby’s weight loss decreases from there. It is one of the reasons for weight loss in babies, as they are still a part of the mother’s body and dependent on the mother for everything.

Baby weight loss after birth is not rare. It is normal for babies to lose a few ounces as they are born with extra fluids that they lose in the first few days after birth.

Do Babies Get Smaller After Birth?

When a baby is born having a weight of more than 0.22-0.28 kgs than the normal weight, then the growth is linked with gestational diabetes. The newborn baby’s length is expected to be between 19 to 21 inches. Approximately one inch of length is expected to grow during the first month of birth. But sometimes, the baby’s weight loss after birth makes them shrink during the first two weeks of coming into life.

So, the answer is yes; occasionally, newborn babies do get smaller after birth.

If your baby comes within this birth weight and length, then your baby is normal, and there is nothing to worry about. Still, if needed, you can contact your practitioner, who might suggest a few extra tests to make sure your baby remains healthy and happy.

Weight of Premature Babies

premature baby weight

Premature babies are smaller and have less weight as compared to full-term babies who are more healthy and have the right birth weight. The premature babies’ weight is completely dependent on the time; that is how early they were born than the normal time. The baby’s weight is low and sometimes very low depending upon the time of birth than usual.

  1. Low Birth Weight: It means the baby’s weight is less than 2,500 grams at the time of birth.
  2. It is Very Low Birth Weight: It means the baby’s weight is less than 1,500 grams at the time of birth.

These small and low birth weight babies need extra care and guidance from both doctor and mother. Most premature babies are kept in the neonatal intensive care unit (NICU) for some time to get proper medical care.

Spurt in Newborn Baby Growth

A newborn baby’s weight is measured or checked by your pediatrician when the baby is 1 or 2 weeks old. Still, you can bring your baby to your pediatrician anytime you want to check the baby’s weight. Don’t trouble yourself by measuring the scale at home, as you may not be able to count those fractions of a pound when it comes to newborn babies.

Basically, it is observed in most of the newborn babies that when the baby gets back to their birth weight, then they start to gain 0.11 to 0.19 kgs in a week for the first 4 to 7 months, which means 0.45 to 0.9 kgs in one month.

If you are feeding your baby formula milk, babies will gain weight faster as formula milk contains higher calories than breast milk. It is also the reason why parents like formula more. But still, if you don’t feel any assurance that your baby is getting enough milk and gaining the right weight and size, then you can notice a few other things.

  1. Count wet diapers in a day – whether s/he produces 9 to 10 wet diapers and 4 to 5 poop.
  2. Most babies face growth spurts at 6 to 10 days old year and again after 3 to 6 weeks of age.

So, it is common and normal that your newborn baby will be extra hungry and needs breastfeeding many times a day. Their weight may shoot up in these periods and may slowly increase in between growth spurts.

Baby Weight Loss After Birth: Is More Than 10% Loss Dangerous?

weight loss in babies

Normal weight loss in newborn babies is 5 to 10%. But sometimes, babies cross the normal rate of weight loss and reach more than 10% of baby weight loss after birth. Then, it is time for the baby to be taken to the doctor. There could be many reasons for weight loss in babies.

Weight loss also depends on how properly they adjust to their weight gaining capacity and schedule. It is also noticed that breastfeeding babies lose more weight compared to bottle-fed babies or formula-fed babies.

However, it is not a healthy way to help your baby to regain the weight that he/she has lost after a few days of life. Any extra baby weight loss after birth can be a serious danger for the newborn baby. The additional weight loss may be because of dehydration, which will result in lower blood circulation. The baby’s heart may get restricted in functioning correctly. These all will lead to serious life-threatening issues.

Due to low amounts of fluid present in the baby’s body, it can slog up sodium levels and affect tissues or cells. Both sodium levels and low fluids can lead to severe damage to the baby’s health. 

Baby Weight Loss After Birth: Other Reasons

Several factors that affect the weight and size of the newborn baby are as follows:

1. Lack of Breast Milk

If you witness a high weight loss after birth, s/he requires the mother’s milk supply at least two to three hours a day to regulate blood circulation.

2. Not Getting Enough Sleep

Some newborn babies are sleepy and the parents need to wake them up for feeding every two to three hours a day. Feeding a sleepy baby is not easy, but it’s essential to make sure that the newborn baby is getting enough milk to gain weight.

3. Facing Trouble To Latch

If the breastfeeding mother has stuffed breasts, big nipples, or flat nipples, the child may face difficulties latching on. This can eventually lead to baby weight loss after birth.

4. Low And Delay In Milk Supply

Due to stress, delays in breast milk production may occur. Other hormonal or physical health issues can also result in a low milk supply. Babies cannot gain weight and length without enough breast milk. 

Getting Enough Breast Milk But Still Not Gaining Weight

Your baby seems healthy and happy and is getting the right breastmilk supply and good sleep. However, you cannot notice any birth weight regain; then the possible reasons could be medical conditions or treatment of the baby or the mother. Sometimes, family factors also affect weight gain in babies.

There are other conditions affecting weight gain also such as infection, past breast surgery, vomiting and improper diet of the mother, etc. So, consult with your doctors regarding this, so that they can suggest some baby supplements which will help babies to start regaining weight.

How To Prevent Excessive Baby Weight Loss After Birth?

  • baby weight loss after birth

If you are concerned about excessive baby weight loss after birth, you must take immediate medical advice from the doctor.

Here are some of the preventive methods that parents can follow to prevent excessive weight loss in newborn babies.

  • Make skin-to-skin contact with your newborn baby to make them feel comfortable and relaxed. This way, the baby will feel better when you feed them.
  • Make a proper feeding and latching position so that the baby can feed your breast milk properly.

Do Bigger Babies Lose More Weight After Birth?

Well, babies who have more weight are better as compared to babies with average weight.

Nearly all babies lose weight after birth despite regular breastfeeding or formula feeding. But that lost weight is regained within 10 to 15 days of the first month.

However, as mentioned earlier, they gain 0.11 to 0.19 kgs after a few months of coming to life. If babies don’t regain lost weight after 7 to 9 days old, then you should consult with your pediatrician to take suggestions.

What Steps Need to be Taken When a Baby Is Losing Weight?

Here are a few steps that need to be taken when your baby is losing weight rather than gaining.

Consult Your Doctor

Consult your doctor to know the real cause of weight loss. Doctors will advise you on the correct information, such as hormonal changes, infection, low breastmilk supply, and other common issues resulting in baby weight loss.

Monitor Baby Weight Loss After Birth

You should measure your infant baby’s weight more often so that you can know the difference in birth weight and after-birth weight. If you think that baby weight loss after birth is too much, then you must increase feeding to 8 to 10 times in 24 hours and keep the time intervals fixed.

Breastfeeding is Important

breast feeding

Your newborn baby is completely dependent on your breastmilk. You should breastfeed more often, at least 3 to 5 times a day. Most babies are often sleepy; wake them to feed them and then make them sleep again.

Breast Milk Needs to Increase

Most of the mother’s breast milk is not as rich in quantity as it should be. It is likely because of your stress, improper sleeping position, or performing too much work or activity. Low breast milk is the possible cause of baby weight loss after birth. Consult your physician to get a lactation consult. Also, include green vegetables, healthy food, and herbs in your diet, which will help increase breastmilk supply.

Give them Time to Drink

Babies take time to finish drinking breast milk, and it is also a fact that the highest fat milk comes late. So, make sure that you feed your baby for 10 to 15 minutes from one breast.

If all these methods don’t work in gaining weight or stopping baby weight loss after birth, you must take the necessary supplements by asking your doctor for a proper prescription. A nursing device for supplementing is also available, which will help to get your baby enough breast milk.

Right Time to Consult Your Pediatrician

After reading all the essential topics related to a baby’s weight loss and weight gain, you must be wondering what is the right time to get recommendations for a consultation?

  • After you get discharged from the hospital with your baby and see any of these cases, then you must consult your doctor:
  • If the baby doesn’t seem to regain the lost weight after 5 days into life or is 1 week old.
  • After gaining her/his lost weight, the baby starts losing weight again.
  • Doesn’t latch properly onto the breast.
  • Gaining too much weight after regaining lost weight.
  • Other signs such as often remains hungry or overeats.
  • The baby doesn’t seem happy even after sleeping or resting for hours.

Take Away

  • First of all, you must keep in mind that every newborn baby grows differently at their own pace, and it is okay if your baby loses or gains weight.
  • Small birth size or large birth size doesn’t define that your baby will be smaller/larger later in life.
  • Most of the babies hit their right growing pace after they turn 5 to 8 years old. There is nothing to consult or worry about your baby’s size or weight before that.
  • And most importantly, babies resemble their parents, so it is normal to be short if the parents are short. If both the parents are tall, then it is quite possible the child will grow tall.

Newborn babies face several common health issues that may be unknown to new parents and may worry them. Baby weight loss after birth is one of them, especially when you are unaware of the reasons for the same. However, more than 12 % of baby weight loss after birth is not a good signal and the newborn should be taken immediately to a pediatrician.

Bindu Raichura,

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