A 4D ultrasound is used in pregnancies to form a real-time image of the developing baby. Sound waves are produced at a high frequency, bounced off tissues, and sent to a monitor that displays the womb and fetus. Standard ultrasounds are only 2D, providing a two-dimensional look at the fetus. While 2D ultrasounds can be effective in some cases, a 4D ultrasound gives a much more detailed look at the baby. Many women receive 4D ultrasounds during their pregnancies for a variety of reasons. Here’s a look at understanding 4D ultrasounds.
Why is my doctor performing a 4D ultrasound?
A 4D ultrasound may be appropriate for many reasons. Your doctor’s imaging technician may perform one to see how the baby is developing, to determine how far along gestation has progressed, or to finding any fetal defects (particularly if a 2D suggests the potential for any concerns). This image can also ensure there’s sufficient amniotic fluid.
This procedure is generally used in the second trimester of pregnancy. The baby's features are usually not developed enough to make the ultrasound worthwhile in the first trimester, and the baby is generally too large to be accurately viewed on a monitor in the third trimester.
What are the advantages of a 4D ultrasound?
The 4D ultrasound allows a physician to see your baby's movements in real time. It’s a more sophisticated form of ultrasound than 2D, thus permitting health care professionals to see the image in more detail and form a more accurate idea of how the fetus is progressing. A trained technician may also be able to locate the baby's features in detail.
This procedure can also help indicate heart defects and a variety of other problems in the fetus. When performed around the fourth or fifth month, your doctor can also take measurements (of the baby and the baby’s developing organs), estimate the baby’s weight, and even determine gender.
How is a 4D ultrasound performed?
Ultrasounds are often performed in private offices as a regular part of prenatal health care visits, although emergency visits may also merit imaging techniques. To begin, your doctor or ultrasound technician will spread a conductive gel over your abdomen. A transducer, which is a tool used to conduct the energy needed to create the ultrasound picture, is rubbed over the area. An image from the transducer is sent to a nearby monitor, from which both you and your healthcare team can view your baby as they move around. Generally, a still shot can be printed so you can keep a picture of your developing baby.
What are the risks of a 4D ultrasound?
Though the small amount of energy emitted from a 4D ultrasound usually isn’t harmful, most experts recommend only having a 4D ultrasound when strictly necessary (generally twice during a normal pregnancy, though sometimes more during high-risk pregnancies). The length of time exposed to the ultrasound waves, the strength of the waves, and the number of ultrasounds performed in a short period of time all influence how risky the procedure(s) may be. If you’re concerned about the safety of the procedure, talk to your obstetrician beforehand.
