Fetal Anatomy Scans

A thorough ultrasound examination of your baby’s anatomy is the most important scan in pregnancy and is recommended for all women. The aim of this scan is to check the baby’s anatomy from head-to-toe and to detect any structural fetal problems. A fetal anatomical problem may be detected in 2-3% of low-risk women and more commonly in women with additional risk factors.

Dr. Colin Walsh is highly experienced in fetal anatomy ultrasound and personally performs all of the scans at SHORE FOR WOMEN.

The fetal morphology (17-22 weeks) scan

The fetal anatomy survey is recommended between 18 and 20 weeks and takes approximately 30 minutes to perform. The aims of this scan are:

  • To detect common structural fetal abnormalities
  • To look for “soft markers” for chromosomal disorders
  • To check the baby’s size and confirm the estimated due date
  • To check the fetal gender (if the parents wish and the baby co-operates!!)
  • To monitor growth in a twin pregnancy
  • To measure cervical length in women at high risk of premature delivery
  • To perform uterine artery Dopplers in women at high risk of fetal growth restriction
  • To take nice keepsake pictures for the parents and family to enjoy

However, it is also important to realise that there are limitations to the fetal anatomy scan:

  • The anatomy scan only provides information on fetal anatomy, not childhood development. It does not tell us anything about behaviour, intelligence or personality.
  • Some fetal structural or genetic problems are very subtle and may not be visible on ultrasound scan or may only develop after birth.
  • The ability to detect fetal problems depends on the image quality. Sometimes babies lie stubbornly in the same position and it is not possible to see al the anatomy – the scan may need to be repeated later that day or another day. Also, image quality may not be as good in women who are overweight.

Early fetal anatomy (12-16 weeks) scan

As ultrasound technology improves, fetal anatomy can be examined earlier and earlier. We do not routinely recommend early fetal anatomy ultrasounds in all pregnancies, as many abnormalities cannot be detected until 18-20 weeks. However, some couples may choose the extra reassurance of having an early fetal anatomy scan. This ultrasound should be considered for:

  • Women who did not have a scan earlier in the pregnancy
  • Couples with a previous child affected by a structural anatomical problem
  • Twin and triplet pregnancies
  • Women with chronic medical problems, such as diabetes, or using certain medications

Other Specialist Ultrasound Lists

  • Mater Hospital
  • North Shore Private Hospital
  • The University Of Sydney
  • Royal College Of Obstetricians and Gynaecologists