Prenatal ultrasounds have been a part of obstetrical care in the United States since the 1970s. For much of that time, simple 2D ultrasounds have been used. These simple scans can diagnose and confirm pregnancy, determine gestational age, estimate fetal size, locate the placenta, and check for multiple pregnancies or fetal malformations, among other things.
Newer 3D and 4D ultrasounds allow parents an even more in-depth look at the pregnancy. Rather than a flat, two-dimensional picture of what is in the womb, the transducer, or probe, can actually take multiple pictures in a series, and then reassemble them as a 3-dimensional image. These images can then become dynamic with the use of 4D ultrasounds; movements and even facial expressions can be seen on the ultrasound images.
Many obstetricians offer simple 2D ultrasounds to their pregnant patients, and there is a belief that 3D and 4D ultrasounds are often simply for entertainment only. However, there can be distinct benefits to receiving the more advanced 3D and 4D ultrasounds.
There are limitations to the diagnostic abilities of 2D ultrasounds. The 3D scans can often pick up clearer images than the 2D ultrasounds, and they may also have a better picture of certain areas than the 2D ultrasounds do.
While 2D ultrasounds can be useful in diagnosing very obvious birth defects, some more subtle ones can be more difficult to see on 2D ultrasound scans. Clubbed feet, polydactyl, facial abnormalities, cleft lips and palate, and even spina bifida may be easier to diagnose using 3D and 4D ultrasonography.
Bonding can also begin earlier for many parents with the use of 3D and 4D ultrasound scans. Often the sex of the baby may be determined earlier than with the traditional 2D ultrasounds, and many parents find that knowing the sex can help them begin to name and bond with the baby. Seeing most distinct facial features and even facial expressions can also be a very attractive proposition for many expectant parents.
Mothers can benefit both emotionally and mentally from having a 3D ultrasound. They can not only receive the reassurance that their baby and pregnancy is progressing as it should, they can bond more closely than ever before birth. If the pregnancy is not progressing as it should, or if the baby has health problems, the advance notice given through the 3D ultrasound can allow the parents the time they need to determine the best course of action for their family.