USG Scan - Foetal Doppler Test

A Doppler scan measures the blood flow through the umbilical cord and around different parts of your baby's body, such as his brain and heart. This helps to show whether he's getting all the oxygen and nutrients he needs via the placenta. You can have a Doppler scan at the same time as a normal scan, as it uses the same equipment. Most ultrasounds have a Doppler function. The person carrying out the scan (sonographer) will put some gel on your tummy and move a hand-held device (transducer) over your skin. The transducer sends out sound waves that bounce off the blood flow to your baby's body via the cord, as well as his blood circulation system. This creates an image on a screen showing the sonographer how the blood is flowing. It gives a good idea of how your baby's doing.

Ultrasound test may be transabdominal or transvaginal. Transabdominal ultrasound, requires a full bladder in the early months of pregnancy to view the shape and heartbeat of the fetus. Transvaginal ultrasound during pregnancy is done with bladder empty or partly filled. It is advisable to wear loose fitting two piece clothing for an ultrasound pregnancy test, so that the examiner can run the probe on the surface of your abdomen.

Doppler ultrasound uses sound waves to detect the movement of blood in vessels. It is used in pregnancy to study blood circulation in the baby, uterus and placenta .Using it in high- risk pregnancies, where there is concern about the baby's condition, shows benefits.

• A radiologist or a sonographer is qualified to perform the Doppler ultrasound scan. The position of the patient depends on the area of the body to be examined.
• For head and neck scans, the patient’s head may be turned to the required side.
• For chest scans, the patient is made to lie on the back with neck slightly extended.
• For abdominal scans, the patient is made to lie on the back.
• For an arm or leg scan, the head of the patient will be slightly raised. The exposed arm or leg will be turned slightly outwards. For some leg scans, the patient may be made to lie on the stomach.
• Doppler scan during pregnancy is done with the patient lying on the back or on the left side with the belly exposed.