Updated March 30, 2015.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Infant Growth: What's Normal?

Like many parents, you might be wondering if your baby is growing normally. However, despite the temptation, it is not recommended to compare your baby's growth and development to other babies. Every child is an individual and grows at his or her own pace.

Growth charts and percentiles are just tools that help track the growth of children over time. The 50th percentile does not mean normal, it means average.

If your child is not in the 50th percentile, it certainly doesn't mean that he or she is not growing at a normal, healthy rate. Many factors contribute to your baby's height and weight, including genetics, diet, and activity level. Normal, healthy babies are in the 5th percentile as well as the 95th percentile.

Weight

During the first few days of life, an exclusively breastfed newborn can lose up to 10% of his or her body weight. This is normal. Within two weeks, most newborns will regain the weight they have lost and return to their birth weight.

By 1 month, the majority of infants will have gained about a pound over their birth weight. At this age, they will be less sleepy, begin developing a regular feeding pattern, and have a stronger suck during feedings.

On average, infants gain approximately a pound per month until they are 6 months old. Most babies will double their birth weight by 5 months of age and triple their birth weight by 1 year old. The average weight of a 6-month-old is about 16 pounds (7.3 kg).

At 1 year old, the average weight is approximately 21½ pounds (9.8 kg). Boys may be bigger than girls, and breastfed infants may weigh less than formula-fed infants.

Height

In general, during the first six months babies will grow approximately an inch per month. Between 6 months and 1 year old, growth typically continues at a rate of about ½ inch per month. The average height at 6 months is approximately 25 ½ inches (65 cm). At 1 year old, the average height is around 29 inches (74 cm).

Growth Spurts

Infants do not grow at a consistent rate. They have times of slower growth and intervals where they grow a significant amount in a short period of time. The surges in growth are called "growth spurts." Growth spurts can occur at any time and do not necessarily follow a pattern. Some common ages that growth spurts can occur are at 10 days, 3 weeks, 6 weeks, 3 months and 6 months old.

Infants require more breast milk during and after a growth spurt. Breast milk is produced based on supply and demand, so the baby will often breastfeed very frequently during these times. The increase in breastfeeding will stimulate your body to make more milk. You may need to breastfeed your baby as much as every two hours. Luckily, the frequent feedings will only last about a day or two as your milk supply adjusts to your growing baby's needs. After that, the baby should settle back into a more regular feeding routine.

Breastfeeding during a growth spurt can be very exhausting. Try to get as much rest as possible and drink plenty of fluids.

If your baby continues to show signs of hunger and nurses very frequently after three days, contact your baby's pediatrician. Your milk supply may be low. The pediatrician can examine and weigh the baby to make sure that he or she is getting enough milk.

Read More: Breastfeeding Tips: Infant Growth Spurts

 

<sub>Sources:

American Academy of Pediatrics. New Mother’s Guide To Breastfeeding. Bantam Dell. New York. 2006.

Johnson, Robert V., MD. Mayo Clinic Complete Book of Pregnancy & Baby’s First Year. William Morrow and Company, Inc., New York, 1994.</sub>