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In the first month, your doctor will pay close attention to your baby's increasing weight, length, and head circumference. The head is measured around the largest point of the head, usually starting at a point on the forehead.
The average birth weight for babies is around 3.5 kg (7.5 lb), although between 2.5 kg (5.5 lb) and 4.5 kg (10 lb) is considered normal. In general:
Newborns often lose around 230 g (8 oz) in the first 4 to 5 days after birth. But they regain it by about 10 to 12 days of age. In the first month, the typical newborn gains about 20 g (0.7 oz) a day, or about 110 g (4 oz) to 230 g (8 oz) a week.
The average length of full-term babies at birth is 50 cm (20 in.). The normal range is 46 cm (18 in.) to 56 cm (22 in.). In the first month, babies typically grow 4 cm (1.5 in.) to 5 cm (2 in.).
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 34.5 cm (13.5 in.). By the end of the first month, it increases to about 37.6 cm (15 in.).
Many babies look a little less than perfect in the first few days or weeks after birth. With time they will gain that cute and healthy baby look. Don't be alarmed if your newborn has:
This is most common with babies who are born vaginally (rather than by caesarean section). Bruising may also occur. Usually the head shape goes back to normal in a few days to a week.
This is caused by swelling during labour 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.
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.
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:
Your baby may lose some or all of the hair that he or she had at birth. This loss is temporary. New hair will replace it. Don't worry if your baby develops bald spots.
Many babies get small pimples on the face. The pimples may appear during the first few weeks of life. They usually clear up on their own within a few months.
Your baby can't adjust to heat or cold very efficiently yet. It's important to keep your baby bundled in the cold and dressed lightly in the heat. Try to keep your home at a stable temperature.
Adaptation Date: 9/6/2023
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services
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