Ch. 25 Growth & Development of the Newborn & Infant
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
30g/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
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
about:blank 1/38
,11/19/23, 8:29 AM Pediatrics Exam 1
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
st
1 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
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
about:blank 2/38
,11/19/23, 8:29 AM Pediatrics Exam 1
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
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
about:blank 3/38
, 11/19/23, 8:29 AM Pediatrics Exam 1
Warning signs that may indicate probs w/language dev infant doesn’t make sounds at 4
months, doesn’t laugh/squeal by 6 months, doesn’t babble by 8 month, doesn’t use single
words w/meaning by 12 months
Social and Emotional Development
Newborn spends most of the time sleeping by 2 months, ready to socialize
First real smile 2 months, should spend a great deal of time watching/observing what’s
going on around
3 months will start an interaction w/a caregiver by smiling widely and maybe gurgling
caregiver responds and child responds back w/more smiling, cooing, arm/leg mvmt
3-4 months mimic parent’s facial mvmts widening eyes, sticking tongue out infant
may cry when pleasant interactions stop
6-8 months may enjoy socially interactive games like peek a boo
Nutrition pg. 977
Breast milk or formula supplies all of the infant’s daily nutritional requirements until 6
months of age, at which time solid foods may be introduced
Breast milk is the preferred method of newborn and infant feeding, it provides complete
infant nutrition
Formula or breast milk for 1 year
After 6 months, infants usually require the nutrients available in solid foods in addition to
breast milk or formula
o Infant should be assessed for readiness to progress and parents need instruction in
choosing the appropriate solid foods and support in the progression
o Tongue extrusion reflex which is needed for sucking needs to be absent
introducing solids foods before 4-6 months will result in extrusion of the tongue
o The ability to swallow foods doesn’t become completely functional until 4-6 months
of age. Enzymes to appropriately digest solid food are also not present until 4-6
months of age
o Solids should be fed w/a spoon in the upright position
Choosing appropriate solid foods
o Iron fortified rice cereal mixed w/a small amount of breast milk or formula is a good
choice for the 1st solid food
o The cereal is easily digested and the taste is generally well accepted
o Once cereal is accepted, other pureed single foods may be introduced
o Intro of one new food every 3-5 days is recommended allows for identification of
food allergies
o Around 8 months ready for more texture in foods soft, smashed table food
without large chunks
o Finger foods cheerios, soft green bean pieces, or soft peas avoid hard food
o 10-12 months can intro strained, pureed, or mashed meats
No bottle propping easy for them to choke
Bottle weaning at 1 year
A cup should be introduced at 6-8 months 1oz of milk in cup while learning newer non
spill sippy cups are not recommended
about:blank 4/38