Lecture 5: Growth Flashcards
Define normal growth
progression of changes in height, weight and head circumference that is comparable with established standards for a given population
What environmental factors influence baby size (pre natal)
Anything that affects placental size: teratogens, chronic maternal conditions affecting nutrition.
- number of fetuses sharing the uterus
What are the most important factors between environment and genetic factors in the growth of babies pre and post natally
Pre natal: More maternal environment
Post natal: More genetic and home environment, ie.
- Diet: breast feeding
- physical illness
- social: financial
- psychosocial: neglect
- parental choice of immunisation
What does head circumference show
Reflection of brain growth as the bones expand and fuse during
How to calculate predicted adult height
Maternal + paternal height / 2 with +/- 6.5 cm for boy or girl
What is delayed/ constitutional delay
This is a normal variant of growth where it is slower but it still follows normal curves.
This leads to a delay in growth and puberty
What are the genetic factors that can lead to tall stature (>97th percentile)
- Chromosomal abnormality: 47xxy / growth hormone excess.
- Tall parents
- Obesity drive growth faster than usually
What are the genetic factors that can lead to short stature (<3rd percentile)
- short parents
- constitutional delay
- look unusual: syndrome
- psychosocial deprivation
- medical problems, growth hormone deficiency
How is growth evaluated
- Take a good history
- Examination
- Plot their growth on a growth chart: a set of data points from a representative population represented as growth curves over time.
How do you interpret a centile
Having a #th percentile places you in this place if you were lined up in a group of 100 others
Why are serial measurements important
They show the infants growth over time and can see whether an infant has changed from one centile to another: more centiles crossed= more significant
When there is failure to thrive, is the drop in growth proportional
The head circumference is less dropping compared to height and weight
What are some abnormalities in head circumference
Microcephaly caused by Vitamin B12 deficiency: causes atrophy of brain and ventricles or Hydrocephaly, enlargement of circumference due to build up of CSF
How do you measure head circumference
Find the area of greatest diameter and measure a couple of times to get an average.
