Every woman in the UK is provided with an individualised growth chart that will map and follow your baby’s growth throughout the final trimester of your pregnancy. The charts are individualised to consider the height, weight, ethnicity, and parity (how many babies mum has had before).
The charts produced after inputting all this information will have the 10th, 50th and 90th centile lines which will later show what your baby's current weight is after the fundal height measurement, and where it is expected to be by your next appointment, compared to other babies at the same gestation. These charts are used alongside fundal height measurements.
Your first measurement will be taken from your 20-week scan, and later, from 28-weeks, your midwife will measure your bump from the top down to your pubic bone. That measurement, taken in centimeters, is then plotted on the chart too.
From 26 to 28-weeks, your midwife will measure your bump at each appointment. Sometimes the measurements trigger a referral for a growth scan. This would happen if:
- The first measurement was below the 10th centile/higher than the 90th centile.
- Later measurements showed a lack of growth (static growth).
- Baby measures larger than expected
Individualised growth charts are a really good way of keeping track of growth, however, measurements are subjective so there is a margin for error. If you see a different midwife, there may be a variance in the way you are measured.
Common Terms You May Come Across
AC - Abdominal circumference (around the abdomen).
BPD - Biparietal diameter (across the head).
Centile - Lines on growth chart to show expected growth (e.g., babies in 50th centile means 50% of babies at same gestation are same weight).
EFW - Estimated fetal weight.
FH - Fundal height.
FL - Femur length (length of thigh bone).
HC - Head circumference (around the head).
SGA/ LGA - Small/large for gestational age.
TCD - Transverse cerebellar diameter (across the cerebellum in the brain).
