Growth and Development

• Growth:

  • Increase in size
  • Increase in mass by multiplication or enlargement
  • Quantitative/measurable (e.g. in, cm, lbs.)
  • 6 important measurements:
  • Height/length, weight, head circumference, abdominal circumference, chest circumference, mid-upper arm circumference
• Development:

  • Increase in function of processes related to body and mind
  • Includes growth
  • Qualitative changes - function and skills are increased
  • Cannot be measured as it involves maturation and differentiation process
  • Highly dependent with different factors: genetics, nutritional, and other environmental factors
• Biopsychosocial Models of Development:

  • Involves extrinsic and intrinsic forces
  • Interrelationship involving:
  • Biologic, Psychologic, Social Influences
• Biologic Influences:

  • Genetic
  • Great impact on growth and development of an individual
  • Physique of children is usually similar to parents
  • IQ is closely related to that of parents
• In utero exposure to teratogens:

  • Teratogens:
  • Tobacco/cigarette smoking: Intrauterine growth retardation (IUGR)
  • Alcohol: fetal alcohol syndrome; IUGR
  • Tetracycline: discoloration of teeth, altered bone growth, hypoplasia of enamels
  • Carbamazepine: neural tube defects
  • Thalidomide: phocomelia/hemimelia
  • Streptomycin: deafness
• Postpartum illness/intrapartum illness:

  • Infections during pregnancy have a great impact on a developing fetus
  • 3 most studied infections:
  • Rubella infection: causes congenital rubella syndrome (CRS)
  • Protozoal infection: e.g. Toxoplasmosis
  • Spirochetal infection: e.g. Syphilis
• Exposure to hazardous substances:

  • Radiation: X-rays during the first trimester show a higher incidence of congenital malformations
  • Actinic rays
• Immunologic factors:

  • Rh and ABO incompatibility affect growth and development towards the end of pregnancy if not managed properly
• Maternal nutrition:

  • Affects brain development
• Endocrine problems:

  • Maternal/Gestational DM
  • Uncontrolled DM will lead to fetal macrosomia
• Other factors:

  • Duration of pregnancy
  • Multiple pregnancies have smaller babies
  • Age of mother is associated with Down Syndrome
  • Parity or order of birth of infant
  • Premature and post-mature babies are smaller in size
• Postnatal factors:

  • Genetic factors
  • Growth potential, size at birth especially in relation to duration of gestation
  • Nutrition
  • Mental deficiency
  • Endocrine disorders
  • Constitutional delay
  • Family value orientation
  • Social deprivation
• Psychologic Influences:

  • Attachment and contingency
  • Child rearing environment
• Social Factors:

  • Family factors
  • Influences outside of mother-child dyad
• Fetal Growth and Development:

  • Newborn Period:
  • From birth up to 1st month of life (28 days)
  • Marked physiologic transitions in all organ systems
  • Infant learns to respond to many forms of external stimuli
  • Parenting of newborn requires dedication, and many factors influence parents' ability to assume the role of caregiver
• Periods of Growth:

  • The First Year:
  • Marked by physical growth, maturation, acquisition of competence and psychologic reorganization
  • Acquire new competencies in all developmental domains
  • Concept of developmental trajectories highlights complex skills build on simpler ones
  • Language: Babbling before words
  • Motor: crawling, standing up, walking, running
• Age 0-2 months:

  • Tremendous growth occurs
  • Establishment of effective feeding routine and a predictable sleep-wake cycle
  • Social interactions between parents and infants are the foundation for cognitive and emotional development
• Measurements:

  • At birth (Filipino child):
  • Weight: 3000 grams
  • Height: 50 cm
  • Head Circumference: 35 ± 2 cm
  • Newborn:
  • Weight may drop 10% during the first week
  • Regains or exceeds birth weight by the 2nd week
  • Gain 30 g/day during the 1st month
• Height:

  • Children: stand erect with the occiput, upper part of back, buttocks and heels against vertical upright centimeter rule. Child's arms should hang naturally on the sides
  • Height (cm) = (Age (yrs) x 5) + 80
  • Height (in) = (Age (yrs) x 2) + 32
• Head Circumference:

  • Taken routinely up to 3 yrs
  • Tape applied firmly over glabella and supraorbital ridges anteriorly and that part of occiput which gives the maximal circumference posteriorly
• Prenatal Development:

  • Organ Development:
  • Muscles:
  • Takes place at the pre-muscular mesodermal tissue
  • Largest increment of muscles mass starts at 4th month of gestation to early maturity
  • Muscular system development:
  • Mid pregnancy: 1/6 of the total body size
  • Birth: 1/5 - 1/4 of total body size
  • Adolescence: 1/3
  • Early adulthood: 2/5
• Cutaneous Development:

  • Epidermis: ectodermal origin
  • Dermis: mesodermal origin
  • Newborn is covered with vernix caseosa and lanugo
• Glands:

  • 1 month: Sweat glands function for temperature regulations
  • 3rd fetal month: hair matrix, sebaceous and apocrine glands are identifiable
• Sweat glands functions for temperature regulations start at 1 month
• Hair matrix, sebaceous and apocrine glands are identifiable at the 3rd fetal month
• Eccrine sweat glands appear at the 5th fetal month
• Axillary and labial glands undergo cyclic changes at puberty
• Axillary, areola, and genitalia skin become hyperpigmented at puberty
• Invasion of dendritic cells of the neural crest starts in the first 3 months of fetal life
• Dermis differentiates into connective tissue containing collagenous and elastic fibers at the 3rd to 4th fetal month
• Scalp hair may be lost or replaced by courser hair at 2 years old
• Pubic and axillary hair appear at puberty and adolescence
• Subcutaneous fat appears during the last 3 months of prenatal development
• Subcutaneous fat increases during the 1st year and diminishes until adolescence
• More subcutaneous fats are present in girls
• Brain development starts at 4 weeks
• 3 main brain divisions are identifiable at 5 weeks AOG
• Myelination completes between 6-12 months old
• Complete myelination is achieved at 7 years old
• Calcification of the pineal gland occurs at 10 years old