Newborn Weight Gain: Healthy Expectations And Growth Rates

A newborn's weight is often used as a marker of general health, so it's understandable that parents and doctors monitor it closely. Babies typically regain their birth weight within 10-14 days of being born and double it by about four months. By the time they turn one, they usually triple their birth weight. However, it's important to remember that babies come in all shapes and sizes, and their weight gain depends on various factors, including genetics, activity levels, and feeding methods.

Newborn weight loss and gain in the first days and weeks

Weight Loss

Newborns usually lose about 5 to 10% of their birth weight in the first few days. This is due to the extra fluid they are born with, which is eliminated in the first few days of life. This weight loss is considered normal and is not a concern unless the baby loses more than 10% of their birth weight.

Weight Gain

Most newborns will start to gain weight again by the time they are 5 to 7 days old. They will typically gain about an ounce (30 grams) per day during their first month, which equates to 5 to 7 ounces per week. By the end of the first month, most babies will weigh between 1 and 2 pounds above their birth weight. They will also grow about 1 to 1.5 inches (2.54 to 3.81 centimeters) in height during this time.

Factors Affecting Weight Gain

There are several factors that can affect a baby's weight gain in the first few weeks, including:

• How quickly the mother's breast milk comes in, if breastfeeding
• How much the baby wants to eat
• Whether the baby is breastfed or formula-fed: breastfed babies tend to gain weight more quickly in the first 3 months, while formula-fed babies gain weight more rapidly after this

Monitoring Weight Gain

It can be difficult to know if your baby is gaining weight at the expected rate, especially if you don't have a suitable scale at home. One way to monitor your baby's weight gain is to count their dirty diapers. In the first five days, a newborn may only wet a few diapers each day, but after that, you should expect about 6 to 8 wet diapers per day. They may only have one dirty diaper a day at first, but this should increase to at least two per day after the first few days.

When to Seek Help

If you are concerned that your baby is not gaining weight at a healthy rate, it is important to speak to your healthcare provider. They may suggest regular weighing of your baby or other measures to ensure they are getting enough nutrition. If your baby has not regained their birth weight by day 10 to 14, has lost too much weight, or their growth is too slow, your pediatrician may refer you to a lactation consultant to identify any underlying problems with feeding.

How to monitor your newborn's weight gain

Weighing your newborn

Newborns are often weighed throughout their stay in the hospital and sometimes again 48–72 hours after discharge. They are then weighed a week after birth and sometimes again two weeks after birth. If a baby has any health concerns, weight checks may be scheduled more frequently.

Most babies should regain lost weight by days 10–14 of life. If a baby loses a significant amount of weight, is sick, or is premature, it may take up to three weeks to get back to their birth weight.

Babies usually start to gain weight again five to seven days after birth, and most should be back to (or above) their birth weight by the time they're about two weeks old. In the first month, newborns typically gain about an ounce (30 grams) daily, or a total of five to seven ounces a week. By the end of the first month, most babies will weigh between one and two pounds above their birth weight.

Monitoring weight gain without a scale

If you don't have a scale at home, you can monitor your baby's food intake in other ways. After the first week, a newborn should have at least five to seven wet diapers a day and at least about three to four dirty diapers a day. (This may change with time, and formula-fed babies tend to have fewer bowel movements than breastfed babies.)

You can also monitor your baby's intake by noticing if your baby seems satisfied for at least a little while after feeding. (Keep in mind that some babies do seem to want to eat all the time!)

When to be concerned

If your newborn hasn't gained back their birth weight by day 10–14, has lost too much weight, or growth is too slow, your paediatrician, often along with a lactation consultant, can help.

Breastfed vs formula-fed babies

Breastfed newborns gain weight faster than formula-fed babies for the first three months of life. This is likely because breast milk is a dynamic and ever-changing food, composed of the exact nutrition a baby needs at that stage. On the other hand, formula is a static composition of ingredients.

Weight gain by week

Here's what you can expect for your baby's weight gain by week:

Average weight gain in ounces

Average weight gain in grams

5–7 ounces per week

4 months to 6 months

4–6 ounces per week

113–150 grams per week

6 months to 12 months

2–4 ounces per week

57–113 grams per week

How much weight should a newborn gain in the first month

Newborns usually lose weight in the first few days of life, but they should be back to their birth weight by the time they are about two weeks old. In the first month, newborns typically gain about an ounce (30 grams) daily, or a total of 5 to 7 ounces a week. By the end of the first month, most babies will weigh between 1 and 2 pounds above their birth weight. They also grow about 1 to 1.5 inches (2.54 to 3.81 centimeters) in height during this month.

Many factors influence a baby's weight gain in the first few weeks of life. These include how quickly a mother's breast milk comes in (if breastfeeding) and how much the baby wants to eat. For example, babies often go through a period of rapid growth when they are 7 to 10 days old and again at 3 and 6 weeks. This is known as cluster feeding.

To ensure your baby is gaining weight at a healthy rate, monitor their food intake and weight gain. In the first week, a newborn should have at least 5 to 7 wet diapers a day and at least about 3 to 4 dirty diapers a day. You should also make sure your baby seems satisfied after feeding. If you have any concerns about your baby's weight gain, don't hesitate to contact your healthcare provider.

What to do if your newborn isn't gaining enough weight

Understand the problem

It's normal for a newborn to lose weight in their first few days of life. Healthy, full-term, breastfed newborns may lose 7-10% of their birth weight, while formula-fed newborns may lose 5% of their birth weight. However, newborns should regain this lost weight within 10-14 days of life. If your newborn doesn't regain their birth weight within this time frame, it could be a sign of slow weight gain or "failure to thrive".

Consult a healthcare professional

If you're concerned about your newborn's weight gain, don't hesitate to consult your healthcare provider. They can assess your baby's weight gain and rule out any underlying medical conditions that may be causing the issue.

Monitor feeding and weight

Keep track of your baby's feeding schedule and weight gain. Newborns should feed about 8-12 times in a 24-hour period. If your baby is not feeding enough, try to wake them up and keep them awake during feedings. You can do this by gently tickling their feet, removing blankets, or easing open their diaper. It's important to understand your baby's feeding cues, such as rooting, making licking or sucking motions, or bringing their hand to their face or mouth. Put your baby to your breast when they cue, and don't wait for them to cry.

Frequent weighing can also help you monitor your baby's weight gain. Digital scales are available that allow healthcare providers to get precise pre- and post-feeding weights, which can help determine how much milk your baby is taking in during a particular feeding.

Improve latching and positioning

Ensure your baby is latching on correctly and is mainly uncovered during breastfeeding. Your baby's lips should be flanged outward, and their tongue should be under your breast. A large amount of your breast tissue should be in your baby's mouth. Massage your breast while your baby nurses to provide a burst of milk and re-trigger sucking.

Boost your milk supply

If you're breastfeeding, try to keep your baby close by, breastfeed frequently, and get plenty of rest. This will help increase your milk supply to meet your baby's demands. Taking postnatal supplements and consuming fenugreek, fennel, milk thistle, and dates may also help increase milk production.

Increase your baby's calorie intake

For breastfed babies, ensure your baby is getting your hindmilk, which has a higher fat content than foremilk. For formula-fed babies, talk to your healthcare provider about the calorie count of the formula and whether any changes are needed. You can supplement your baby's calorie intake with your own expressed milk or formula, but always offer the breast before the bottle if you plan to continue breastfeeding.

How weight gain differs for breastfed and formula-fed babies

Newborns tend to lose weight in their first few days of life, but they usually regain it within the first two weeks. After that, they start gaining weight, with most babies doubling their birth weight by about four months. However, the rate of weight gain differs for breastfed and formula-fed babies.

Weight Gain in Breastfed Babies

Breastfed babies tend to gain weight more slowly than formula-fed babies during the first year. This is because breast milk is dynamic and changes according to the baby's nutritional needs. As a result, breastfed babies may drink less milk than formula-fed babies, but they still get all the calories and nutrients they need.

Weight Gain in Formula-Fed Babies

Formula-fed babies gain weight more rapidly than breastfed babies after the first three months. This is because formula has a static composition, so when they need more calories, they must drink more at each feeding. Additionally, it is easier to accidentally overfeed formula-fed babies since caregivers may be more likely to keep feeding until the bottle is empty.

Tracking Weight Gain

It is important to track a baby's weight gain to ensure they are feeding well and getting the necessary nutrients. Both breastfed and formula-fed babies should be weighed regularly during well-baby visits to ensure they are within the normal range for their length and age. It is okay for a baby's weight gain to deviate from the average as long as they are consistently gaining weight at their own pace.

Frequently asked questions