Standard Ultrasound Sonogram

A standard ultrasound sonogram uses a transducer to emit sound waves into a woman's uterus. The sound waves scan the uterus and return to the transducer, producing a 2-D image of the fetus.

Advanced Ultrasound Sonogram

An advanced ultrasound sonogram focuses on a specific targeted area, and it uses higher powered equipment for greater scanning detail. The resulting product is a closeup black and white 2-D image of the fetus.

Doppler Ultrasound Sonogram

The doppler ultrasound sonogram is able to detect the slightest movements in cells, such as red blood cells. It is used primarily to monitor blood flow through the baby. It can show blood clotting in the fetus, and it also shows a rhythmic graph of the baby's heartbeat.

Transvaginal Ultrasound Sonogram

Often used during early stages of pregnancy, the transvaginal ultrasound is taken using a probe that is inserted inside the woman's vagina to view her reproductive and internal organs. The image is an enhanced version of a 2-D ultrasound sonogram.

Fetal Echocardiography

This ultrasound specifically uses sound waves to monitor the baby's heart. The sonogram image shows a closeup 2-D view of the baby's heart. Specialists can then study the image for any irregularities or potential development problems.

3-D and 4-D Ultrasound Sonograms

Enhanced cameras provide digital 3-D pictures of the baby. 4-D ultrasounds specifically show closeup scans of the baby's face. Sonograms tend to be displayed in sepia tones rather than black and white. They allow for a realistic first view of the baby's facial expressions and characteristics.

Source:

American Pregnancy Organization

Radiology Information: Ultrasounds

Cleveland Clinic: Transvaginal Ultrasounds