Third trimester ultrasound:
the growth scan

Traditionally, women with uncomplicated pregnancies were not scanned again once the 20 week ultrasound was completed. However, an ultrasound in the third trimester of pregnancy is better than clinical examination at picking up growth problems, breech babies and other concerns. We recommend that all women have at least one 3rd trimester ultrasound (also called a growth scan). You may need more than one growth scan if your pregnancy is high risk.

A third trimester scan is definitely recommended if:

  • You are measuring small or large for your dates
  • Your baby is breech or in an unusual position
  • You have high blood pressure, pre-eclampsia or diabetes
  • You have a pre-existing medical problem or take certain medications
  • You are having twins or triplets
dr Colin Walsh - Ultrasound scan

The main aim of the third trimester ultrasound is to measure the size of your baby and ensure the baby is growing normally. Abnormal fetal growth is a sign of an underlying problem. Babies who are abnormally small (fetal growth restriction) or large (macrosomia) need careful monitoring and an individualized plan for the rest of the pregnancy.

We also look at the placenta and amniotic fluid volume, the position of the baby in the uterus and observe fetal movements as part of a well being check.

Finally, Doppler ultrasound is an advanced test of fetal wellbeing usually performed in combination with a growth scan. Dr Walsh is highly experienced in fetal Doppler ultrasound and has performed Doppler studies in thousands of high-risk pregnancies.

We offer the full range of specialist obstetric ultrasound scans. Please click on the links below for more information :