@katrina2017 https://utswmed.org/medblog/3d-4d-ultrasound/
From the link above:
2-D, 3-D, and 4-D ultrasounds: What’s the difference?
All ultrasounds use sound waves to create an image of your baby in the womb:
A regular 2-D ultrasound creates a cross-sectional view of your baby.
In a 3-D ultrasound, many 2-D images are taken from various angles and pieced together to form a three-dimensional image. This looks more like what you’re used to seeing in a typical photograph.
4-D is similar to 3-D, but it shows movement, so you can see your baby kicking or opening and closing their eyes.
So why don’t we use 3-D all the time if we have the capability to do so? Simply, 2-D often is more efficient. We usually don’t need 3-D to assess how your baby is developing. While 3-D can give a nice picture of the outside of your baby, 2-D ultrasound is really the standard that has been developed by experts to look for abnormalities in development and growth of your baby.
However, 3-D and 4-D ultrasounds can be important tools to assess some abnormalities that are hard to look at in 2-D, such as cleft lip. They also are helpful when we need to explain an abnormality to parents. While doctors and sonographers may be able to easily recognize it in a 2-D image, parents are often able to better visualize the abnormality in a 3-D image.
Are ultrasounds safe for your baby?
The ultrasound waves used to image the baby expose the baby to energy in the form of heat. Under some circumstances, heat can lead to birth defects. That’s why we adhere to a principle while performing ultrasounds called ALARA: as low as reasonably achievable. That means we are careful with the settings on the ultrasound machine so we use as low amount of power as necessary and we limit the amount of time needed to obtain images, thereby exposing the developing baby to the least amount of energy possible.
In its warning against commercial use of ultrasound, ACOG endorsed this statement from the American Institute of Ultrasound in Medicine: “Although there are no confirmed biological effects on patients caused by exposures from present diagnostic ultrasound instruments, the possibility exists that such biological effects may be identified in the future. Thus ultrasound should be used in a prudent manner to provide medical benefit to the patient.”
Concerns about keepsake ultrasounds
Forty weeks can feel like a lifetime to wait to see your baby. 3-D and 4-D ultrasounds can seem like the perfect solution to get a sneak peek of your little one. Upon seeing one of these ultrasounds, I’ve heard parents say, “Oh, he’s got his grandfather’s nose,” or, “She looks just like her sister when she was born.”
But when you go outside the medical setting to get a 3-D or 4-D ultrasound, we worry about a couple things.
Qualifications of the person performing the ultrasound
If you get a 3-D or 4-D keepsake ultrasound outside of a medical setting, the person performing the ultrasound is focused on getting a good photo and video for you, not assessing the health of your baby. They may not have the same rigorous training that a certified ultrasound facility requires of its sonographers.
If they see something they are uncomfortable with, they may not be prepared to provide you with information, support, or follow-up. In those cases, you may need to go to your doctor for another ultrasound. This can result in unnecessary anxiety and concern.
Commercial ultrasounds also may result in false reassurance. Some women interpret a pleasing photo as evidence of healthy development. If the person assessing the ultrasound isn’t a trained medical professional, they may not have the skills to notice that something isn’t right with the baby or other structures like placenta and umbilical cord.
