Ultrasound Scanning is now considered a routine practice in ascertaining the viability, and progress of a pregnancy. It is also used for congenital abnormality screening. Most women expect and look forward to a scan to check that all is well with their baby. Some women however, view scanning as an unnecessary intervention and decline them. It is your choice whether you have ultrasound scanning during your pregnancy, and your LMC can give you a referral form and advise you of the stage in your pregnancy that is best recommended to have each scan done.
Obstetric Ultrasound is the use of ultrasound scans in pregnancy. Since its introduction in the late 1950’s ultrasonography has become a very useful diagnostic tool in Obstetrics.
Currently used equipments are known as real-time scanners, with which a continous picture of the moving fetus can be depicted on a monitor screen. Very high frequency sound waves of between 3.5 to 7.0 megahertz (i.e. 3.5 to 7 million cycles per second) are generally used for this purpose.
They are emitted from a transducer which is placed in contact with the maternal abdomen, and is moved to “look at” (likened to a light shined from a torch) any particular content of the uterus. Repetitive arrays of ultrasound beams scan the fetus in thin slices and are reflected back onto the same transducer.
The information obtained from different reflections are recomposed back into a picture on the monitor screen (a sonogram, or ultrasonogram). Movements such as fetal heart beat and malformations in the feus can be assessed and measurements can be made accurately on the images displayed on the screen. Such measurements form the cornerstone in the assessment of gestational age, size and growth in the fetus.
A full bladder is often required for the procedure when abdominal scanning is done in early pregnancy. There may be some discomfort from pressure on the full bladder. The conducting gel is non-staining but may feel slightly cold and wet. There is no sensation at all from the ultrasound waves.
In Palmerston North there are three places you can go for a Pregnancy Ultrasound. Palmerston North Hospital, Broadway Radiology, and Manawatu Ultrasound. Palmerston North hospital provides free scanning, but can be very busy and difficult to get an appointment. Broadway Radiology and Manawatu Ultrasound are private Radiology centres so it will cost you approximately $50 for a scan after the first trimester.

