Stages of Ultrasounds

Ultrasounds are routinely performed during prenatal care. The first ultrasound, which usually takes place at the end of the first trimester, is a very exciting time for parents. Ultrasounds may be performed at subsequent visits, especially when birth defects or other pregnancy-related problems are suspected. Ultrasounds are also useful for other applications, such as stroke and blood-vessel-related disorders.

Transvaginal Ultrasound

• Transvaginal ultrasound is used to diagnose problems with a woman's reproductive organs or to assess fetal development during the very early stages of pregnancy. Transvaginal ultrasound involves insertion of a probe, called a transducer, into a woman's vagina. Sound waves produced by the transducer reflect off tissues, creating a sonogram of the woman's reproductive organs or a developing fetus.

  During certain situations, when distension of the vaginal walls is needed for a clearer image, a saline infusion sonogram is performed. For this procedure, a saline solution is infused into the uterus before the insertion of the transducer.

Standard 2-D and Advanced Ultrasound

• During the first trimester of pregnancy, doctors perform a standard ultrasound, which produces a 2-D image. Parents are able to view this sonogram on a television monitor during the ultrasound procedure. The standard 2-D ultrasound is useful to determine the exact stage of gestation, for monitoring the baby's development and for detecting potential birth defects.

  Advanced ultrasound procedures use more sophisticated equipment to read the ultrasound and provide specific data. Through this additional data physicians are informed of potential problems.

3-D and 4-D Ultrasound

• Three-dimensional and four-dimensional ultrasounds require additional equipment and operator training. Three-D is useful when birth defects are suspected. In 3-D, the doctor is able to view the developing fetus with greater volumetric measurements. In other words, the doctor can see a modeled image. Four-D, sometimes called dynamic ultrasound, allows the doctor to view movements.

  Both 3-D and 4-D ultrasounds are gaining popularity with parents because of the accuracy and detail of the images of the baby. Through viewing these advanced ultrasound images, parents experience more rapid bonding with their child.

Doppler Ultrasound

• Doppler ultrasound is used by obstetricians to monitor special health problems or birth defects of babies. It is also used by other specialists to monitor venous blood flow, kidney and liver function, and amount and location of plaque in arteries. Doppler ultrasound relies upon the change in pitch of sound waves as they bounce off of blood flowing through veins or arteries. There are three types of Doppler ultrasound: bedside or continuous, color and duplex.

Fetal Echocardiography Ultrasound

• Fetal echocardiography ultrasound is used when a developing fetus is experiencing problems with its heart. Through this highly specialized form of ultrasound, specialists are able to view heart function and diagnose problems. Many times doctors are able to correct these defects in utero.