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Obstetrical or Pregnancy Ultrasound

Ultrasound is a safe and widely used imaging technique. Ultrasound produces detailed pictures of the body in real-time using high frequency sound waves, which are produced by a special ultrasound probe, called a transducer. The probe sends sound waves into the body and then "listens" for echoes reflected back from body structures. The frequency of these sound waves is higher than that detected by the human ear and are detected by the probe when they are reflected by a part of the body. An ultrasound image is produced from these detected echoes based upon their intensity and time taken to return to the probe.  The images are captured in real time on the monitor and appear as both static and moving images enhancing the diagnostic capability of the test. Ultrasound has no known harmful effects. 

Pregnancy ultrasounds may be performed by examination of the abdomen called transabdominal or by using a special probe designed to be inserted into the vagina, called transvaginal. The type of examination you will need will depend on what your referring doctor has requested and the nature of the clinical condition being investigated. Transvaginal ultrasound is commonly performed in early pregnancy.

Hours of operation:  Monday through Saturday (no Sunday appointments)

Who will perform the scan?

Your examination or scan will be performed by a fully certified trained ultrasonographer.  Because the examiner is interpreting moving images on a screen, a high degree of concentration is required to obtain accurate information. Therefore, family and friends of the patient are not generally permitted to watch the procedure and will be asked in at the end of the scan to view images of baby. If you have accompanying children, you will have to bring along someone to watch them during your examination.

Preparation for day of appointment

  • Drink 5 large glasses of fluids (no carbonated drinks) and be FINISHED 1 hour BEFORE appointment time (e.g. If exam at 12:00 pm - finish drinking by 11:00 am)
  • Arrive with a FULL BLADDER
  • Do not use the washroom or void after you’re done drinking until the ultrasound is complete
  • No food restriction (you may eat)
  • Continue your medications as usual


For most ultrasound examinations, you will be required to change into a gown and lie on an examination stretcher. You will remain covered during your examination except for the area being imaged. In order to obtain optimal images, a layer of gel will be applied to the area being imaged so that good contact is made between you and the ultrasound probe. The probe will be placed directly onto the gel and your skin for the duration of the examination. You may also be asked to hold your breath for a few seconds during the scan time. The scan is completely painless, although pressure may be applied to improve the image quality. Please tell the sonographer should this become uncomfortable.

In some instances, a transvaginal scan may be indicated. Transvaginal scans are frequently performed in the first trimester of pregnancy and also in the late stages of pregnancy and at other times to get a close-up view of the pelvic organs. The transvaginal scan is performed with an empty bladder and, as a result, many patients find it more comfortable. The small, sterilized probe, about the same diameter as a thumb, is lubricated with gel before insertion into the vagina. A protective cover (a condom) is placed over the transducer each time it is used, so there is no risk of infection. Transvaginal scans are only performed if requested or clinically indicated and always with the patient’s consent. Please discuss any issues you may have with the sonographer.

Indications for Pregnancy Ultrasound

Ultrasound is a highly valuable diagnostic tool and particularly useful during pregnancy because it is completely safe for you and your baby. Some of the useful indications for use during pregnancy include:

  • 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.

Most ultrasound examinations will be completed within 45-60 minutes, however, some studies will take longer especially if a transvaginal scan is indicated after the initial ultrasound is performed. The radiologist will then interpret all images produced during the examination and the results will be forwarded to your doctor within 2-3 business day. We can provide you with some still pictures should you wish. We do not provide videotapes or allow patients to use electronic devices during the ultrasound examination.

Day of your Appointment

Patients should arrive 15 minutes before their appointment time. Patients arriving late may be rescheduled.

Please bring your health card and requisition. 

Please be aware that this is a "Fragrance Free" facility. Please ensure that you are not wearing perfume or scented products.

Please do not bring small children to your appointment, unless accompanied by another adult.

Directions & Parking

Park park off of Noxon St., in the Visitor parking lot, located to the southeast, south and southwest of the hospital. Enter the hospital through the Registration/Emergency (ER) Entrance. Continue to Registration, just up the hall and on the left.

If you have any questions or need to re-schedule your appointment, please contact our scheduling department at 519-485-9611 (Monday-Friday 9:00-5:00).

NOTE: If not properly prepared, the examination will be rescheduled.