Ch. 25 Growth & Development of the Newborn & Infant
2025-2026
Principles of Development
• Continuous process through life
• Orderly sequence
• Predictable but unique ranges
• Systems mature at different rates
• More rapid in early periods
• Cephalocaudal pattern grow longer, head to tail
• Gross to refined skills
• Newborn/neonatal period of infancy from birth to 28 days
• Infancy 28 days to 12 months
Growth & Development
• Nurse must be familiar w/normal development while obtaining health hx, nurse can ask
parent/caregiver if the skill is present and when it was attained
• Ill or premature infants may exhibit delayed acquisition of physical growth and dev skills
when assessing the growth and dev, use the infants adjusted age to determine expected
outcomes
• Adjusted age subtract the # of weeks that the infant was premature from the infant’s
chronological age
Physical Growth
• Ongoing assessments of growth are important so too rapid or inadequate growth can be
identified
• Infants grow rapidly over the first 12 months weight, length, head and chest circumference
are all indicators of growth
• Weight
o The avg newborn weighs 3.4 kg (7.5lb) at birth o Newborns lose up to 10% of their
body weight over the 1st week of life then gain
30 g/day and regains birth weight by 10-14 days of age o Most infants double their
birth weight by 4 months and triple by the time they are 1 y/o
• Height
o Avg newborn is 50cm (20in) long
o Length grows more quickly over the 1st 6 months o By 12 months length increased
by 50%
• Head Circumference o Avg head circumference of full term newborn 35cm (14in) o
Increases rapidly during 1st 6 months o Avg of 10 cm (4in) gain from birth to 1 y/o
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• Fontanel closure posterior 6-8 weeks (2 months), anterior at 9-18 months open for brain
to grow pg. 1179
• Teeth
o Occasionally and infant is born w/1 or more teeth natal teeth or dev them in 1st 28
days neonatal teeth
o Majority do not have teeth when born 1st teeth erupt btwn ages 6 & 8 months
primary teeth (deciduous teeth)
Causes ↑ saliva & drooling
Enzyme released w/teething causes mild diarrhea, facial skin irritation
Slight fever may be associated; not high fever (normal) o Gums around
emerging tooth will usually swell lower central incisors are usually
1st to appear followed by upper central incisors o
The avg 12-month old has 4-8 teeth
o Put toys in freezer to help w/inflammation or baby Orajel
• Stranger Anxiety pg. 973 o May develop at around the age of 8 months
o Previously happy and friendly infant may become clingy and whiny when
approached by strangers
o Stranger anxiety indicator that the infant is recognizing themselves as separate
from others
o As the infant becomes more aware of new people/places they may view a stranger
as threatening even if parent is there
o Fam members that don’t see the child often approach infant calmly and slowly
w/parent in sight sometimes will prevent a sudden crying spell
• Separation Anxiety o May start is last few months of infancy
o Infant becomes distressed when parent leaves infant will eventually calm down &
become engaged w/caregiver
o 8 months’ protests loudly when mom leaves
• Adaptive Behaviors
• Gross Motor Skills pg. 968
• Large muscles head control, rolling, sitting, & walking
• Dev in cephalocaudal fashion ex. Baby learns to lift the head before learning to roll over &
sit
1 month Lifts and turns head to side in prone position, head lag when pulled to sit,
rounded back in sitting
2 months Raises head & chest, holds position. Improving head control
3 months Raises head to 45 degrees in prone, slight head lag in pull-to-sit
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4 months Lifts head & looks around, rolls from prone to supine, head leads body
when pulled to sit
5 months Rolls from supine to prone and back again, sits w/back upright when
supported
6 months Tripod sits
7 months Sits alone w/some use of hands for support
8 months Sits unsupported
9 months Crawls, abdomen off floor
10 months Pulls to stand. Cruises
12 months Sits from standing position. Walks independently
Warning signs that may indicate probs w/motor dev arms and legs are stiff or floppy, child
cannot support head at 3-4 months of age, child reaches w/one hand only, child cannot sit
w/assistance at 6 months, child doesn’t crawl by 12 months, child cannot stand supported
by 12 months of age
• Fine Motor Skills pg. 969
• Includes the maturation of hand and finger use dev in a proximodistal fashion (center to
the periphery)
• Ex. A newborn’s hand movements are involuntary in nature whereas a 12-month old is
capable of feeding themselves
• By 12 months the infant should be able to eat with their fingers & assist w/dressing
( pushing an arm through the sleeve )
1 month Fists mostly clenched, involuntary hand mvmts
3 months Holds hand in front of face, hands open
4 months Bats at objects
5 months Grasps rattle
6 months Releases object in hand to take another
7 months Transfers object from one hand to the other
8 months Gross pincer grasps (rakes)
9 months Bangs objects together
10 months Fine pincer grasp. Puts objects into container and takes them out
11 months Offers objects to others and releases them
12 months Feeds self w/cup and spoon. Makes simple mark on paper. Pokes w/index
finger
• Language Development
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• For several months, crying is the only means on communication of newborn and infant
crying = unmet needs
• 1 to 3 month coos, makes other vocalizations, and demonstrates differentiated crying
• 4 to 5 months simple vowel sounds, laughs aloud, “raspberries,” and vocalizes in response
to voices, responds to their name and begins to respond to “no”
• 4 to 7 months distinguishes emotions based on the tone of voice
• 6 months squealing and yelling, could be displeasure or joy
• 7 to 10 months babbling begins and progresses to strings (mamama, dadada) without
meaning, can respond to simple commands
• 9-12 months beings to attach meaning to “mama” and “dada” and starts to imitate other
speech sounds
• The average 12-month old uses 2-3 recognizable words w/meaning, recognizes objects by
name, and starts to imitate animal sounds
• Very impt for caregiver to talk to infant to learn communication skills
• Sometimes regression in language dev occurs briefly when the child is focusing energy on
other skills (crawling, walking)
• As long as hearing is normal, language should progress continually
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