Fetal Anomaly Scan

20 weeks

This scan is usually the second chance for the scanner to reassure how about how the structure of your baby is forming.

Earlier scans will have confirmed the dates and ascertained the number of babies as well as obtaining an early overview of your baby's structure.

At this stage your baby is much bigger and can be seen in its infant form and is the time at which most parents really start to relate to their baby on the screen.

At this appointment the sonographer will:

• Show your baby’s heart beating
• Check growth by measuring the head, waist and thigh bone (femur) of your baby
• Look at your placenta and the amount of fluid around your baby
• Examine the structure of your baby’s organs in detail

If no previous scans have been done, then all the steps described are performed but of course it may mean that this is the first time that dates are ascertained or twins are diagnosed!

22 - 24 weeks

Many consultants prefer that the examination of your baby should be performed a little later so that extra information can be obtained.

All the tasks outlined in the 20 week scan are performed as well as some additional tests which only become meaningful at this time.

These additional features are:

• Blood flow from the mother to the uterus (uterine artery Doppler) is checked. This gives early warning about the possibility of bleeding in later pregnancy, blood pressure complications (pre eclampsia) or the possibility of a slowing in your baby’s growth later in the pregnancy.
• A transvaginal ultrasound is performed to measure the length of the neck of the womb (the cervix). A shortened cervix increases the chance of the mother going into labour before your baby’s due date.

For bookings information and prices please see our Appointments page.