intra-uterine growth
embryonic and fetal
growth (assessed by birthweight)
gestational age
Post-menstrual age
* ie. number of weeks + days since 1st day of last menstrual period
What is full-term?
38-42 weeks post-menstrual age
What is considered pre-term?
<37 weeks
What is considered low birthweight?
<2500 g at delivery
How is newborn growth assessed?
Measurements of length, weight, head circumference are done at delivery and assessed using growth charts
* Throughout pregnancy women is measured for size and then compared to infant measurements → provides information about patterns of intra- uterine growth
When do adaptations happen which effect a newborn?
Adaptations occur in-utero to adverse circumstances
* increase short-term survival
* permanent alterations in structure or function occur during “critical periods” of development
What are the patterns for intra-uterine growth?
What is the birthweight classification used for?
Method of describing the likelihood of adverse outcomes
* type of problem depends on birthweight classification and etiology (cause)
Factors affecting etiology of SGA
Infant factors affecting etiology of SGA?
placental factors affecting etiology of SGA
maternal factors affecting etiology od SGA?
(“environmental”)
* smoking
* alcohol
* drugs
* undernutrition
Risks associated with SGA
what are long term risks of SGA related to?
Typically in utero adaptations
infant factors effecting etiology of LGA
genetics
Maternal factors affecting etiology of LGA
uncontrolled/poorly controlled diabetes
* Many LGA babies not at ↑ risk, but infant of a diabetic mother (IDM) is at ↑ risk
Risks associated with all LGA
birth injury both the mom and baby
Risks associated with IDM with LGA
What is IDM
Infants of Diabetic Mothers
How do growth charts work?
Variability at given age defined by percentiles which is proportion of population found below a specific value
* Age along x-axis; anthropometric (weight, length, head circumference) measure on y-axis
* Also weight for length: length x-axis; weight measure on y-axis
What is the expected pattern along the growth chart for an infant?
Maintenance of growth along “own” percentile
* Birthweight reflects prenatal growth factors, postnatal growth dependent on different factors including genetic potential
* Crossing percentiles between 0 and 24 months not uncommon
When is it important to do a follow up in an infants growth pattern?
What are important considerations considering growth patterns?
Consider birthweight, previous growth pattern, gestational age, genetics, type of feeding, presence of a condition/disease