What is an Obstetrics or Pregnancy Ultrasound?

What is a Doppler Ultrasound

Obstetrics or Pregnancy Ultrasound is a very valuable diagnostic tool during pregnancy because it is completely safe for you and your baby. Some of the useful indications for use during pregnancy are:

  • for dating purposes and to accurately determine your due date
  • to ascertain the number of babies present
  • to check for any bleeding early in the pregnancy
  • to check the position of the placenta
  • to assess the growth of the baby and its general well-being
  • to provide information about the anatomy of the baby and check for possible abnormalities*

*not all possible birth abnormalities are reliably diagnosed using ultrasound and all scan results should be interpreted within the limitations of the test.

It is common for pregnancy scans to be requested by your doctor or specialist at different stages during pregnancy, including in the first, second or third trimester.  Typical pregnancy ultrasounds are:

  • Dating scans, to determine your baby’s due date, are usually offered between the 6th and 12th weeks of pregnancy. These may be offered as a transvaginal Female Pelvic Ultrasound.
  • Anatomy or Anomaly scans, used to check the baby’s anatomy and assess growth usually take place between 18 to 20 weeks of gestation.

Obstetrics Ultrasound

What happens during an Obstetrics Ultrasound?

A. Before your scan

What to bring

  • Your request form
  • Any relevant previous imaging
  • Your Medicare card and any concession cards

Preparation – the day of your procedure

Depending on the stage of pregnancy you are in and the type of scan, preparation is as follows:

Early Pregnancy Scan

Gradually drink 1 litre of water up to one hour prior to exam. It is very important not to empty your bladder. You can continue to take any current medication as usual.

Anatomy Pregnancy Scan

Drink 1 litre water half an hour prior to your appointment and do not empty your bladder prior to your scan. Continue to take any current medication while preparing for your scan.

For most ultrasound examinations you will be required to change into a gown and lie on an examination couch. You will remain covered during your examination except for the area being imaged.

B. During your Obstetrics Ultrasound


You will be made comfortable on the examination table and asked to uncover the area being examined.

Gel will be applied to the area being imaged to help create a good contact between you and the ultrasound probe. The probe will be placed directly onto the gel and your skin for the duration of the examination. The sonographer will move the probe around on your skin at different angles to obtain images. The scan is completely painless, although some pressure may be applied to improve the image quality.  Please tell the sonographer if this becomes uncomfortable.

Your ultrasound will be performed by a Radiologist (medical specialist) or a sonographer (a specially trained technologist). Because the examiner is interpreting moving images on a screen a high degree of concentration is required.

Most Preganancy Ultrasound examinations will be completed within 30-60 minutes. It is not unusual for the radiologist to come in and speak with you and view the images on the screen. At the end of the procedure the gel is simply wiped from your skin so that it does not mark your clothes.

Risks and side effects

Ultrasounds are a very low risk procedure and complications are rare however you should be informed of the possible risks and side effects.

Risks associated with this procedure include:

  • If scanning is performed over an area of tenderness, you may feel pressure or minor pain from the transducer.

Any medical procedure can potentially be associated with unpredictable risks.

Who will perform my Obstetrics Ultrasound?

Your ultrasound will be performed by a Radiologist (medical specialist) or a sonographer (a specially trained technologist).

Obstetrics Ultrasound

What happens after an Obstetrics Ultrasound?

How do I get my results?

After your appointment, the information from your scan is interpreted by Envision’s Radiologist before delivery of a report to your doctor.


You should be able to go about your daily activities after your appointment.