What is the average birth weight of a full term baby

On the other hand, a full-term baby born at 5. There are many different factors used to determine a baby's birth weight, including age, genetics, and certain lifestyle factors of the mother. However, research has also shown a connection between advanced maternal age and high birth weight as well.

Genetics also play a role in birth weight. The genetic characteristics of both parents are important. One difference, however, is that the mother's weight at her own birth has a greater impact than the father's birth weight. Mothers who smoke tend to have smaller babies, as physiological changes related to smoking reduce the nutrients supplied to the baby. In , 7. Maternal nutrition can also affect an infant's birth weight.

A mother's weight gain in pregnancy is influenced by different factors, including her socioeconomic conditions, pregnancy and non-pregnancy related health conditions, and genetics.

A lack of early and regular prenatal care has been associated with lower birth weight babies. The health of an infant's mother and father can also affect a newborn's birth weight. While many factors can be modified, there are some factors that cannot be changed, such as:. If your baby is full-term, of normal birth weight, and has no medical conditions, it's not usually necessary to weigh your baby as long as they are eating well, have wet diapers, and are developing normally.

Your pediatrician will check your newborn's weight at each well-child visit and let you know if there is any cause for concern. If your infant is low birth weight, was born prematurely, or your pediatrician has any other concerns, you will likely be asked to make more frequent visits to the clinic for weight checks.

Average weight gain can vary for children who are born with low birth weight or are large for gestational age. For example, premature babies often undergo catch-up growth.

If your baby was born early, your pediatrician will explain growth expectations. Otherwise, your baby's weight gain by age can be monitored using the following guidelines.

Babies usually lose weight at first. Babies usually regain their birth weight by 10 to 14 days of age. In the first 3 months of life, babies gain an average of 1.

Your pediatrician will talk about normal growth rates for young children. Your doctor can also show you where your child is on a growth chart —a graph that compares your baby's height and weight to other babies of the same age. Between the age of 4 months and 6 months, babies put on weight less rapidly at around 1 to 1.

Birth weight is usually tripled by around 1 year of age. On average, your baby's weight will roughly quadruple by the time they are about 2 and a half years old. The birth weight of babies can vary and will be affected by many factors. A baby's birth weight does not necessarily predict a child's adult size.

Some very-low-birth-weight babies grow up to be quite tall or large, while large-for-gestational-age babies might be small adults. Whatever your baby's birth weight is, your pediatrician will help you understand the growth expectations for your baby. They can use graphs to show you where your child falls in terms of their growth, and how their growth might affect their health. Get it free when you sign up for our newsletter. Healthwise Staff. University of Michigan Medicine.

Physical Growth in Newborns. Updated August 21, Stanford Children's Health. Small for Gestational Age. Large for Gestational Age. Births: Provisional data for Vital Statistics Rapid Release.

National Vital Statistics System. Updated March 26, Birthweight and Gestation. Updated March 31, Births: Final data for National Vital Statistics Reports. Children's Hospital of Philadelphia. Karnik S, Kanekar A. Childhood obesity: a global public health crisis. Int J Prev Med. Many newborns go through a period of rapid growth when they are 7 to 10 days old and again at 3 and 6 weeks.

Newborns are so small, and it can be hard to know if your baby is gaining weight the way he or she should. You may worry that your baby has lost too much weight in the first few days or isn't taking enough breast milk or formula. If so, talk to your doctor, who may ask you about:. Being small or large at birth doesn't mean a baby will be small or large later in childhood or as an adult.

Plenty of tall teens began life as small babies, and the biggest baby in the family can grow up to be a petite adult. By the time they're adults, kids tend to resemble their parents in size.

Genetics , as well as good nutrition and your attention, will play a large part in how your baby grows in the years to come. Whether your baby starts out large, small, or average, in the next few months you can expect your little one to keep growing fast. Reviewed by: Madhu Desiraju, MD. Larger text size Large text size Regular text size. How Big Are Newborns? Other factors include: Size of parents. Big and tall parents may have larger-than-average newborns; short and petite parents may have smaller-than-average newborns.

Multiple births. If you have twins, triplets, or more, you can count on your babies being a bit small. Multiples have to share their growing space in the uterus, and they're often born early, which leads to small size at birth. Birth order. First babies are sometimes smaller than brothers or sisters born later. Girls tend to be smaller, boys larger, but the differences are slight at birth. Mom's health during pregnancy. Things that can lead to a lower birth weight include a mother with high blood pressure or heart problems; or one who used cigarettes , alcohol , or illegal drugs during the pregnancy.

If the mother has diabetes or is obese, the baby may have a higher birth weight. Nutrition during pregnancy. If your practitioner schedules fewer appointments, feel free to bring your baby in for a weight check anytime.

Plus, many nursing and new mom support groups have baby scales so you can get a quick read. After about 4 months, formula-fed babies will gain at a slightly faster rate because formula has more calories than breast milk, and parents tend to push baby to finish bottles as opposed to letting them stop at the breast whenever they want. Many babies go through a growth spurt at 7 to 10 days old, and then again at 3 weeks and 6 weeks of age.

Baby's weight might shoot up during these periods, and increase more slowly in between growth spurts. Some common issues include:. What if your baby is packing on the pounds faster than 7 ounces a week? If that just happens over the course of one week, you might be in the middle of a growth spurt. And some newborns simply grow faster than others. If your baby is exclusively breastfed, it's unlikely that you're overfeeding her, and the extra weight gain is probably just a sign of her growing appetite.

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