Growth and Developmental Milestones

Milestones of Prenatal Development

Prenatal Developmental Events

• Week 1 Fertilization and implantation; beginning of embryonic period
• Week 2 Endoderm and ectoderm appear (bilaminar embryo)
• Week 3 First missed menstrual period; mesoderm appears (trilaminar embryo); somites begin to form
• Week 4 Neural folds fuse; folding of embryo into human-like shape; arm and leg buds appear; crown-rump length 4-5 mm
• Week 5 Lens placodes, primitive mouth, digital rays on hands
• Week 6 Primitive nose, philtrum, primary palate
• Week 7 Eyelids begin; crown-rump length 2 cm
• Week 8 Ovaries and testes distinguishable
• Week 9 Fetal period begins; crown-rump length 5 cm; weight 8 g
• Week 12 External genitals distinguishable
• Week 20 Usual lower limit of viability; weight 460 g; length 19 cm
• Week 25 Third trimester begins; weight 900 g; length 24 cm
• Week 28 Eyes open; fetus turns head down; weight 1,000-1,300 g
• Week 38 Term

Developmental Milestones in 1^st 2 Year of Life

Gross Motor Milestones

• Holds head steady while sitting - 2 months: (Allows more visual interaction)
• Pulls to sit, with no head lag - 3 months: (Muscle tone)
• Brings hands together in midline - 3 months: (Self-discovery of hands)
• Asymmetric tonic neck reflex gone - 4 months: (Can inspect hands in midline)
• Sits without support - 6 months: (Increasing exploration)
• Rolls back to stomach - 6.5 months: (Truncal flexion, risk of falls)
• Walks alone - 12 months: (Exploration, control of proximity to parents)
• Runs - 16 months: (Supervision more difficult)

Fine Motor Milestones

• Grasps rattle - 3.5 months: (Object use)
• Reaches for objects - 4 months: (Visuomotor coordination)
• Palmar grasp gone - 4 months: (Voluntary release)
• Transfers object hand to hand - 5.5 months: (Comparison of objects)
• Thumb-finger grasp - 8 months: (Able to explore small objects)
• Turns pages of book - 12 months: (Increasing autonomy during book time)
• Scribbles - 13 months: (Visuomotor coordination)
• Builds tower of 2 cubes - 15 months: (Uses objects in combination)
• Builds tower of 6 cubes - 22 months: (Requires visual, gross, and fine motor coordination)

Communication and Language Milestones

• Smiles in response to face, voice - 1.5 months: (More active social participant)
• Monosyllabic babble - 6 months: (Experimentation with sound, tactile sense)
• Inhibits to "no" - 7 months: (Response to tone (nonverbal))
• Follows 1-step command with gesture - 7 months: (Nonverbal communication)
• Follows 1-step command without gesture - 10 months: (Verbal receptive language (e.g., "Give it to me"))
• Says "mama" or "dada" - 10 months: (Expressive language)
• Points to objects - 10 months: (Interactive communication)
• Speaks first real word - 12 months: (Beginning of labeling)
• Speaks 4-6 words - 15 months: (Acquisition of object and personal names)
• Speaks 10-15 words - 18 months: (Acquisition of object and personal names)
• Speaks 2-word sentences (e.g., "Mommy shoe") - 19 months: (Beginning grammatization, corresponds with 50-word vocabulary)

Cognitive Milestones

• Stares momentarily at spot where object disappeared - 2 months: (Lack of object permanence (out of sight, out of mind; e.g., yarn ball dropped))
• Stares at own hand - 4 months: (Self-discovery, cause and effect)
• Bangs 2 cubes - 8 months: (Active comparison of objects)
• Uncovers toy (after seeing it hidden) - 8 months: (Object permanence)
• Egocentric symbolic play (e.g., pretends to drink from cup) - 12 months: (Beginning symbolic thought)
• Uses stick to reach toy - 17 months: (Able to link actions to solve problems)
• Pretend play with doll (e.g., gives doll bottle) - 17 months: (Symbolic thought)

Emerging Patterns of Behavior During the 1st Year of Life

Neonatal Period (1st 4 wk)

• Prone: Lies in flexed attitude; turns head from side to side; head sags on ventral suspension
• Supine: Generally flexed and a little stiff
• Visual: May fixate face on light in line of vision; doll's eye movement (oculocephalic reflex) of eyes on turning of the body
• Reflex: Moro response active; stepping and placing reflexes; grasp reflex active
• Social: Visual preference for human face

At 1 mo

• Prone: Legs more extended; holds chin up; turns head; head lifted momentarily to plane of body on ventral suspension
• Supine: Tonic neck posture predominates; supple and relaxed; head lags when pulled to sitting position
• Visual: Watches person; follows moving object
• Social: Body movements in cadence with voice of other in social contact; beginning to smile

At 2 mo

• Prone: Raises head slightly farther; head sustained in plane of body on ventral suspension
• Supine: Tonic neck posture predominates; head lags when pulled to sitting position
• Visual: Follows moving object 180 degrees
• Social: Smiles on social contact; listens to voice and coos

At 3 mo

• Prone: Lifts head and chest with arms extended; head above plane of body on ventral suspension
• Supine: Tonic neck posture predominates; reaches toward and misses objects; waves at toy
• Sitting: Head lag partially compensated when pulled to sitting position; early head control with bobbing motion; back rounded
• Reflex: Typical Moro response has not persisted; makes defensive movements or selective withdrawal reactions
• Social: Sustained social contact; listens to music; says "aah, ngah"

At 4 mo

• Prone: Lifts head and chest, with head in approximately vertical axis; legs extended
• Supine: Symmetric posture predominates, hands in midline; reaches and grasps objects and brings them to mouth
• Sitting: No head lag when pulled to sitting position; head steady, tipped forward; enjoys sitting with full truncal support
• Standing: When held erect, pushes with feet
• Adaptive: Sees raisin, but makes no move to reach for it
• Social: Laughs out loud; may show displeasure if social contact is broken; excited at sight of food

At 7 mo

• Prone: Rolls over; pivots; crawls or creep-crawls (Knobloch)
• Supine: Lifts head; rolls over; squirms
• Sitting: Sits briefly, with support of pelvis; leans forward on hands; back rounded
• Standing: May support most of weight; bounces actively
• Adaptive: Reaches out for and grasps large object; transfers objects from hand to hand; grasp uses radial palm; rakes at raisin
• Language: Forms polysyllabic vowel sounds
• Social: Prefers mother; babbles; enjoys mirror; responds to changes in emotional content of social contact

At 10 mo

• Sitting: Sits up alone and indefinitely without support, with back straight
• Standing: Pulls to standing position; "cruises" or walks holding on to furniture
• Motor: Creeps or crawls
• Adaptive: Grasps objects with thumb and forefinger; pokes at things with forefinger; picks up pellet with assisted pincer movement; uncovers hidden toy; attempts to retrieve dropped object; releases object grasped by other person
• Language: Repetitive consonant sounds ("mama," "dada")
• Social: Responds to sound of name; plays peek-a-boo or pat-a-cake; waves bye-bye

At 1 yr

• Motor: Walks with one hand held; rises independently, takes several steps (Knobloch)
• Adaptive: Picks up raisin with unassisted pincer movement of forefinger and thumb; releases object to other person on request or gesture
• Language: Says a few words besides "mama," "dada"
• Social: Plays simple ball game; makes postural adjustment to dressing

Emerging Patterns of Behavior From 1-5 Year of Age

15 MO

• Motor: Walks alone; crawls up stairs
• Adaptive: Makes tower of 3 cubes; makes a line with crayon; inserts raisin in bottle
• Language: Jargon; follows simple commands; may name a familiar object (e.g., ball); responds to his/her name
• Social: Indicates some desires or needs by pointing; hugs parents

18 MO

• Motor: Runs stiffly; sits on small chair; walks up stairs with 1 hand held; explores drawers and wastebaskets
• Adaptive: Makes tower of 4 cubes; imitates scribbling; imitates vertical stroke; dumps raisin from bottle
• Language: 10 words (average); names pictures; identifies 1 or more parts of body
• Social: Feeds self; seeks help when in trouble; may complain when wet or soiled; kisses parent with pucker

24 MO

• Motor: Runs well, walks up and down stairs, 1 step at a time; opens doors; climbs on furniture; jumps
• Adaptive: Makes tower of 7 cubes (6 at 21 mo); scribbles in circular pattern; imitates horizontal stroke; folds paper once imitatively
• Language: Puts 3 words together (subject, verb, object)
• Social: Handles spoon well; often tells about immediate experiences; helps to undress; listens to stories when shown pictures

30 MO

• Motor: Goes up stairs alternating feet
• Adaptive: Makes tower of 9 cubes; makes vertical and horizontal strokes, but generally will not join them to make cross; imitates circular stroke, forming closed figure
• Language: Refers to self by pronoun "I"; knows full name
• Social: Helps put things away; pretends in play

36 MO

• Motor: Rides tricycle; stands momentarily on 1 foot
• Adaptive: Makes tower of 10 cubes; imitates construction of "bridge" of 3 cubes; copies circle; imitates cross
• Language: Knows age and sex; counts 3 objects correctly; repeats 3 numbers or a sentence of 6 syllables; most of speech intelligible to strangers
• Social: Plays simple games (in "parallel" with other children); helps in dressing (unbuttons clothing and puts on shoes); washes hands

48 MO

• Motor: Hops on 1 foot; throws ball overhand; uses scissors to cut out pictures; climbs well
• Adaptive: Copies bridge from model; imitates construction of "gate" of 5 cubes; copies cross and square; draws man with 2-4 parts besides head; identifies longer of 2 lines
• Language: Counts 4 pennies accurately; tells story
• Social: Plays with several children, with beginning of social interaction and role-playing; goes to toilet alone

60 MO

• Motor: Skips
• Adaptive: Draws triangle from copy; names heavier of 2 weights
• Language: Names 4 colors; repeats sentence of 10 syllables; counts 10 pennies correctly
• Social: Dresses and undresses; asks questions about meaning of words; engages in domestic role-playing