Doctors and health care providers help you to keep a track of your newborn’s baby’s weight, length, and head size newborn’s first day for you. But why all this interest in your baby’s size? This is primarily because the baby’s growth is a good indicator of its general health. A child who is growing well is generally healthy, while poor growth can be a sign of a problem.

Various factors can affect a baby’s size at birth. In many cases, the length of the pregnancy is a key factor. Babies born at their due date or later tend to be larger than those born earlier. Babies born prematurely, as discussed below, are often smaller than full-term babies

Just like adults, newborns come in a range of healthy sizes. Most babies who are born full-term (between 37 and 40 weeks) weigh somewhere between 6 pounds, 2 ounces (2,812 grams) and 9 pounds, 2 ounces (4,173 grams). The average length for a full-term infant usually ranges from 19 to 21 inches (48 to 53 centimeters). These figures can vary.

Babies are born with some extra fluid, so it is perfectly normal for a newborn to drop a few ounces when that fluid is lost in the first few days of life. A healthy newborn is expected to lose 7% to 10% of his or her birth weight but should regain that weight by about 2 weeks after birth.

During their first month, most newborns continue to gain weight at a rate of at least 5 ounces (141 grams) a week. They generally grow in height about 1 to 1.5 inches (2.54 to 3.81 centimeters) during the first month. Many newborns go through a period of rapid growth when they are 7 to 10 days old and again at 3 and 6 weeks.

It is indeed difficult to track the growth in newborn seamlessly because they are so small. Thus you may worry that your baby has lost too much weight in the first few days, or that he or she isn’t taking enough breast milk or formula. On most occasions everything would be fine. But for any concern you feel you have, immediately consult your doctor.