Baby Weight Gain


A normal newborn usually weighs between 5 and 10 pounds with an average around 7 pounds. Weight is one of the first things people want to know about a newborn and all parents worry about whether or not their baby weighs too much or too little. How do you know if your baby is gaining weight normally and what to do if your baby is not?

What’s Normal Baby Weight Gain After Birth?

Weight gain after birth follows some fairly predictable patterns as indicated in the table below:


Length Increase

Weight Increase

Birth to 6 months

0.5-1 inch (1.5 to 2.5 cm) each month

5-7 ounces (140 to 200 grams) per week

6-12 months

0.45 inch (about 1 cm) each month

3-5 ounces (85 to 140 grams) per week

Your baby’s pediatrician will keep track of baby weight gain and will usually plot the growth on a height/weight nomogram. Do not get too concerned if your baby’s weight fluctuates from week to week; much more important is that the baby continues to grow and gain weight over the months from one doctor’s appointment to the next. Click here to learn normal baby weight gain by month in both boys and girls as well as ways to help healthy growth. 

Should I Be Worried About Baby Not Gaining Weight Normally?

In general, your baby will gain and lose weight during his first year of life. When the baby’s healthcare provider gives you the growth chart (or nomogram), watch the trend over time. It’s important to remember that children will normally lose weight during the first week of life, but will quickly catch up during the next few weeks. If you think your baby is not gaining enough weight, it is time for a visit to your baby’s doctor. As you track the baby’s growth on the chart, if he falls below the 3rd percentile for weight, or if he is 20% lighter than his ideal weight you need to contact the baby’s doctor.

How Will the Doctor Determine If You Baby Suffers from Failure to Thrive?

  • Feeding patterns. During this visit, the baby’s healthcare provider will ask about the baby’s feeding schedule. Be prepared to tell the provider how many feedings the baby is taking each day. For a newborn, it is normal for your baby to eat every 2-3 hours. The doctor will also want to know how much the baby is eating. For a normal baby, each feeding will last about 10 minutes. If the baby is taking a bottle, this usually means the baby will eat about 3-4 ounces at each feeding with an increase of one ounce for each month of age after the first.
  • Bowel movements and urination pattern. The baby’s healthcare provider will also want to know how often the baby urinates and how many bowel movements she has. Normally, the baby will have between 4 and 6 wet diapers each day. Bowel movements of newborns will vary but should NOT be formed. Your baby should also be alert when he is awake and should not have a fever. If you have concerns about any of these things, be sure your healthcare provider knows about the issue.
  • The diagnosis. If the doctor is concerned about your baby’s weight and growth, he may order lab work and may ask you to keep track of feeding patterns over a period of time. Failure of your baby to grow is not your fault and your healthcare provider will help you reverse this “failure to thrive”.

Causes of Abnormal Baby Weight Gain 

There are many reasons your baby may not be gaining weight normally. For example:

  • A low birth weight or very young baby may fall asleep before he gets enough to eat;
  • The baby’s sucking power may not be enough to provide him enough to eat;
  • If breastfeeding, you may not be producing enough milk;
  • If you are stressed, the letdown reflex that causes milk to flow into your breasts may be affected;
  • If you are trying to keep your baby on a strict feeding schedule, she may not be getting enough milk when she needs it; try feeding on demand;
  • If your baby has been sick, she may not be feeding as well. As she is treated for her illness, continue to offer feedings and she will start eating again.
  • If he has stomach or digestive problems (including vomiting or diarrhea), your baby will not be able to gain weight normally. Have the baby seen by his doctor.
  • Be sure you are taking care of yourself. If you are depressed or preoccupied, you will not be able to give your baby the attention he deserves and he may simply not be getting enough to eat.

How to Tell If My Baby’s Had Enough to Eat

With a bottle fed baby, you will know exactly how much he is eating each day. But, if you are breastfeeding, it is a little trickier to know how much he is eating. If your breasts become soft and more comfortable after feeding, chances are your baby is getting enough to eat. Watch him during feeding to make sure his sucking is strong and that he is swallowing. If he is having at least six wet and several dirty diapers each day, he is probably getting enough to eat. Probably the most important indicator of whether or not your baby is getting enough to eat is whether or not she seems to be satisfied after eating. Often, a satisfied baby will go to sleep shortly after eating.