3D scanning uses advanced ultrasound technology to produce imaging in three planes. These can then be reconstructed so that the images appear to be as you would see the structure in real life.
4D scanning adds the extra dimension of time to 3D imaging, so that the 3D image is moving in real time. Note that whilst 3D/4D scanning will usually be attempted during the procedure, it may not always be possible to obtain perfect views. This is usually because the fetus is not in a good position.
Please note that we are a medical practice and do not do scans just for 3D/4D views of the baby