First Aid for the Pediatrics Clerkship, 3 Ed.

Growth and Development



Image Understanding normal growth patterns of childhood is important because it is an indication of the overall health of a child.

Image Growth is influenced by both genetics and environment.

Growth Charts

Image Height, weight, and head circumference are plotted on growth curves to compare the patient to the population.

Image Growth charts compare individual children with the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles.

Image Serial plotting of a patient’s growth allows the clinician to observe patterns of growth over time.


Having only one point on a growth chart is like having no point; the trend over time is what is important.

Image Body mass index (BMI) is plotted on growth curves for males and females from 2 to 20 years of age. BMI above 85% classifies as overweight and above 95% as obese.

Image Potential limitations of particular growth charts include possible development from small population sizes, ethnic differences, and whether they represent growth potential versus proper care and feeding.

Image Specialized charts exist for children who are premature (Babson), have Down syndrome, myelomeningocele, Prader-Willi syndrome, cerebral palsy, or Williams syndrome.


In the normal child, the greatest growth occurs in the first year of life.

Early Growth Trends

Image A term infant regains birth weight by 2 weeks.

Image During the first 3 months, a child is expected to gain 20 to 30 g/day or close to 1 kg/month.

Image A child doubles birth weight by the fifth month of life and triples by his or her first birthday.

Image Growth chart recording should be adjusted for gestational age until the infant is 2 years old.

Image Children with genetic short stature may have normal length and weight at birth but their growth percentiles decline within the first 2–3 years.

Image Appetite normally Image in the second year of life coincident with the slowing of the growth rate.

Intrauterine Factors


Carefully plotting on a growth chart is the most accurate method by which to follow a child’s physical growth.

Image Insulin-like growth factor (IGF) is important for fetal growth.

Image Growth hormone and IGF are both important for postnatal growth.

Image Thyroid hormone is important for central nervous system (CNS) development, but not important for fetal growth.

Image Fetal weight gain is greatest during the third trimester.

Image Teratogens, TORCH infections (toxoplasmosis, other [hepatitis B, syphilis, varicella-zoster virus], rubella, cytomegalovirus, herpes simplex virus/human immunodeficiency virus), and chromosomal abnormalities (trisomy 21, Turner syndrome) can impair fetal growth.


Image By age 2½, children should have all of their primary teeth including their second molars.

Image Central incisors are first to erupt, between 5 and 8 months.

Image Second molars are last to erupt, between 20 and 30 months.

Image Secondary (permanent) teeth begin to erupt by age 6–7 years.

Image Early or late tooth eruption may be within normal limits, though it can be an indicator of a nutritional, genetic, or metabolic problem.

Image Delayed eruption:

Image Endocrine disorders (hypothyroidism).

Image Genetic abnormalities (Down syndrome).




Head circumference > 3 standard deviations below the mean for age and sex.


Image Genetic (familial, isolated).

Image Syndromic:

Image Chromosomal: Trisomy 21, 13, 18.

Image Contiguous gene deletion: Cri-du-chat syndrome, Williams syndrome.

Image Single-gene defects: Cornelia de Lange syndrome, Smith-Lemli-Opitz syndrome.

Image Prenatal insults (radiation, alcohol, hydantoin, TORCH infections, maternal phenylketonuria [PKU] and maternal diabetes, Image placental blood flow).

Image Perinatal hypoxic-ischemic encephalopathy.

Image Structural malformation (eg, lissencephaly),


Measure parents’ and siblings’ head circumference to check for familial cause of microcephaly.


A small brain predisposes to cognitive/motor delay, mental retardation, and seizures.


Weight is affected first in FTT, followed by height and head circumference.



Head circumference > 3 standard deviations above the mean.


Image Familial in 50% of cases.

Image Hydrocephalus.

Image Other causes: Large brain (megalencephaly), cranioskeletal dysplasia, Sotos syndrome.


Psychosocial reasons account for most cases of FTT in the United States.

Failure to Thrive (FTT)


FTT is defined as a weight below the third percentile or a fall off the growth chart by two percentiles.


Signs of FTT:


Subcutaneous fat loss

Muscle atrophy


Lagging behind norms






Image Organic causes include disease of any organ system.

Image Nonorganic causes include abuse, neglect, and improper feeding (see Table 4-1).


Image Expected age norms for height and weight not met.

Image Hair loss.

Image Loss of muscle mass.

Image Subcutaneous fat loss.

Image Dermatitis.

Image Lethargy.

Image Recurrent infection.

Image Kwashiorkor—protein malnutrition.

Image Marasmus—inadequate nutrition.


Image Detailed history:

Image Gestation, labor, and delivery.

Image Neonatal problems (feeding or otherwise).

Image Breast-feeding mother’s diet and medications.

Image Types and amounts of food, who prepares and how the formula or food is prepared, who feeds.

Image Vomiting, diarrhea, infection.

Image Sick parents or siblings.

Image Major family life events/chronic stressors.

Image Travel outside the United States.

Image Any injuries to child.

Image Observation of parent-child interactions, especially at feedings, is critical for diagnosis.

Image Lack of weight gain after adequate caloric feedings is characteristic of nonorganic failure to thrive.

Image Screening tests for common causes include complete blood count (CBC), electrolytes, blood urea nitrogen (BUN), creatinine, and albumin and thyroid-stimulating hormone (TSH).


Image If a nonorganic cause is suspected or the child is severely malnourished, hospitalization may be required.

Image If organic, treat the cause.


Organic versus nonorganic FTT is best distinguished by a detailed history and physical exam.


FTT during the first year of life has a poor outcome due to the rapid growth of the brain during the first 6 months.

TABLE 4-1. Etiology of FTT





A child smiles spontaneously, babbles, sits without support, reaches, and feeds herself a cookie but has no pincer grasp. What is her approximate age? Think: 8–9 months (immature pincer grasp at 10 months). Fine pincer grasp of an object between the thumb and forefinger generally develops at 12 months of age.

Image Attainment of developmental milestones is an indicator of a child’s overall neurologic function.

Image Maturation of intellectual, social, and motor function should occur in a predictable manner.

Image It is essential that the physician recognize normal patterns in order to identify deviations.

Developmental Milestones

Image Each new motor, language, and social skill should be acquired during an expected age range in a child’s life.

Image Each new skill is built on an earlier skill, and skills are rarely skipped (see Table 4-2).

TABLE 4-2. Developmental Milestones




Neurologic Development

Image Myelination of the nervous system begins midgestation and continues until 2 years of age.

Image Myelination occurs in an orderly fashion, from head to toe (cephalocaudal).

Image Brain at birth weighs approximately 10% of the newborn’s body weight (adult brain, 2% of body weight).

Image Primitive reflexes are present after birth and diminish by 6 months (see Table 4-3).


For age adjustment between birth and 2 years, subtract the number of weeks of prematurity from the chronological age. For an 18-month-old baby who is an ex-preemie at 30 weeks, the difference from full term at 40 weeks is 10 weeks, so the corrected age is 18 months minus 10 weeks = 15½ months.

Age Adjustment for Preterm Infants

Image Preterm infants may differ from full-term infants with regard to development.

Image Age correction should be done until the child is 24 months old for children born more than 2 weeks early.

Image Use the corrected age when assessing developmental progress and growth.

TABLE 4-3. Primitive Reflexes





An 18-month-old infant brought in for temper tantrums has normal gross and fine motor skills but lacks language development and is cooperative and alert on exam. Think: Hearing loss.

Screening for hearing in the newborn nursery before discharge has resulted in earlier detection of hearing loss. Hearing impairment impacts language development. Inattention may be the initial presentation. It can also affect behavior and academic achievement.


Developmental Evaluation

12 months: No babbling and no gesture

16 months: No single word

24 months: No two-word phrase


Image Performance significantly below average in a given skill area.

Image Global developmental delay: Significant delay in two or more areas of development (gross or fine motor, speech and language, cognition, social and personal, and activities of daily living).

Image Early detection of delay is important because brain development is most malleable in the early years of life.


At age 1 year, a child uses one word and follows a one-step command.


Image Cerebral palsy.

Image Mental retardation.

Image Learning disabilities.

Image Hearing and vision deficits.

Image Autism.

Image Neglect.

Image Attention deficit/hyperactivity disorder (ADHD).

Image Lack of exposure.


At age 2 years, a child uses two- to three-word phrases and follows two-step commands, and others can understand half of the child’s language.


Image The Denver Development Assessment Test (Denver II) is a screening tool intended to be performed at well-child visits to identify children with developmental delay.

Image For children up to the age of 6 years.

Image Evaluates personal-social, fine motor, gross motor, and language skills.


At age 3 years, a child uses three-word sentences, and others can understand three fourths of the child’s language.

Image Clinical Adaptive Test (CAT)/Clinical Linguistic Auditory and Milestone Scale (CLAMS) rates problem solving, visual motor ability, and language development from birth to 36 months of age.

Image Early intervention is important because the younger children are treated, the better the outcome.


At age 4 years, a child should be 40 lbs. and 40 inches tall, and be able to draw a four-sided figure.


Image Present in 3–10% of children.

Image To make a diagnosis of learning disability, the child must have a normal

Image Include difficulties with reading (dyslexia), arithmetic (dyscalculia), and writing (dysgraphia).

Image Dyslexia is one of the most common learning disabilities.

Image Failure to acquire reading skills in the usual time course.

Image These children have excellent spoken language.

Image Presents with different degrees of severity.


Image Infants sleep 18 hours per day, with 50% rapid eye movement (REM) sleep, compared to an adult with 20% REM sleep.

Image By age 4 months, nighttime sleep becomes consolidated.

Image Two sleep stages are REM (irregular pulse and time when dreaming occurs) and non-REM (deep sleep).

Image Parasomnias (sleep disorders) begin near age 3 years.

Image Nightmares occur during REM sleep—the child awakens in distress about a dream.

Image Night terrors occur in non-REM sleep—the child appears awake and frightened but is not responsive, and then is amnestic about the event the next morning.

Image Somnambulism (sleepwalking) occurs in non-REM sleep; most common in ages 4–8 years.

Image Somniloquy (talking) is very common throughout life, sometimes accompanying night terrors and sleepwalking.

If you find an error or have any questions, please email us at Thank you!