A 3D ultrasound is able to achieve remarkably clear images by utilising the same sound waves used in a 2D ultrasound but bending them in different angles. The clarity of the images available offers many advantages over 2D ultrasounds, but it also comes with some disadvantages.
A 3D Ultrasound provides a more detailed image of the baby than a traditional 2D Ultrasound. The images are more lifelike and give a great indication of what your baby's physical features will look like. A 3D ultrasound is able to give a very clear image of the babys facial features after the fifth month.
Unlike a traditional 2D Ultrasound it is not necessary to have a full bladder in order to obtain a clear image. Needless to say this is a great relief to expectant mothers.
The remarkably clear images can provide a false sense of reassurance that there are no underlying physical problems with the unborn baby. Mothers to be may decide that getting a 3D ultrasound is the cheap alternative to a more substantial prenatal care program and may discontinue this prenatal care under the assumption "everything is ok." While a good tool for determining the physical condition of an unborn baby. 3D ultrasound should never completely replace all other prenatal care options.
Can give a false indication of the health of the baby i.e. does not always accurately represent physical deformities. These "false positives" can become more of an issue with an inexperienced ultrasound technician. For example; harmless fetal cysts detected by 3D ultrasounds, may lead to further and more invasive tests can contribute to additional anxiety by the mother. There is also the possibility of "scanning artifacts" such as duplicated body parts, holes and unusual clefts, which usually go away after the ultrasound probe has been moved slightly. An inexperienced technician might be guilty of making this error. Again this can cause undue stress and anxiety to the mother.
Ultimately the decision to go for 2D or 3D ultrasound is influenced by the level of information the expected mother wishes to receive. Sometimes too much information is not a good thing, however, and it can lull you into a false sense of security. Sometimes it is exactly what you need. In the end the choice is yours.