In the first month, your doctor will pay close attention to your
baby's increasing weight, length, and head circumference, which is measured
around the largest point of the head, usually starting at a point on the
The average birth weight for babies is around
7.5 lb (3.5 kg), although
between 5.5 lb (2.5 kg) and
10 lb (4.5 kg) is considered
normal. In general:
Boys are usually a little heavier than
First babies are usually lighter than later
Large parents generally have large babies, while small
parents generally have small babies.
Newborns often lose around
8 oz (226.8 g) in the first 4
to 5 days after birth but regain it by about 10 to 12 days of age. In the first
month, the typical newborn gains about
0.7 oz (20 g) a day, or
about 4 oz (110 g) to
8 oz (226.8 g) a
The average length of full-term babies at birth is
20 in. (50 cm), although the
normal range is 18 in. (45.7 cm) to
22 in. (60 cm). In the first
month, babies typically grow
1.5 in. (4 cm) to
2 in. (5 cm).
Your baby's head will grow at its fastest rate during the first 4
months after birth than at any other time. This increase is due to rapid brain
growth. The average head circumference at birth is about
13.5 in. (34.5 cm). By the end
of the first month, it increases to about
15 in. (37.6 cm).
Many babies look a little less than perfect in the first few days or
weeks after birth. Gradually they will gain that cute and healthy baby look. Do
not be alarmed if your newborn has:
An irregularly shaped head, often referred to as
the "cone-head." This is most common with babies who are born vaginally (rather
cesarean section). Bruising may also
occur. Usually the head shape returns to normal in a few days to a week.
Squinty-looking, bloodshot eyes. This is caused by swelling during
labor and delivery. Also, antibiotic eye ointment given in the hospital can
make your baby's eyes look gooey or small. Your baby's eyes will start to look
larger and brighter within a couple of weeks.
Downy hair on
forehead, cheeks, shoulders, and back. This is especially common in babies who
are born earlier than their due date. It will usually go away within a few
weeks after birth.
Swollen breasts or genitals. This occurs in both
boys and girls when the mother's hormones pass to the baby during birth. Some
babies may even have some milky fluid come out of the nipple. Baby girls may
have blood-tinged fluid from their vagina.
Other physical developmental issues to be aware of in your baby's
first month include:
Hair loss. Your baby may lose some or all of the
hair that he or she had at birth. This loss is temporary and new hair will
replace it. Do not worry if your baby develops bald spots.
skin conditions. Many babies develop small pimples on the face. The pimples may show up during the first few weeks of life and usually clear up on their own within a few months. For more information, see the topic Newborn Rashes and Skin Conditions.
Lack of ability
to self-regulate temperature. Your baby is not yet able to adjust to heat or
cold very efficiently. It is important to keep your baby bundled when it is
cold and dressed lightly when it is very warm. Try to keep your home at a
How this information was developed to help you make better health decisions.