A sonogram is an image that results from a sonograph, or ultrasound. A baby sonogram is an image of a growing fetus that allows doctors and other specialists to check on the health of the pregnancy and identify any underlying health conditions that require immediate treatment.

Sonography, or fetal ultrasound, is a procedure that uses sound waves to create an image of the developing fetus in the womb.

There are two main types of ultrasound examinations, transvaginal and transabdominal. Doctors usually decide which type to use according to the pregnancy stage and condition.

This article provides an overview of sonograms, including the different types of ultrasound scans, how each works, and what someone can expect during an ultrasound appointment.

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A sonogram is an image created when ultrasonic sound waves bounce off tissue. An ultrasound machine is a device that a sonographer uses to generate a sonogram. Fetal, or prenatal, ultrasound is another name for a sonogram of a fetus.

Unlike X-rays, ultrasound machines do not use ionizing radiation. This makes them safer and more convenient to use.

During a fetal ultrasound scan, a sonographer uses a transducer to send sound waves through the body. These waves interact with the internal organs and tissues in the body before returning as echoes. The transducer turns these echoes into images of what is happening in the body.

There are two main types of sonograms, or fetal ultrasounds:

Transvaginal ultrasound.

Some people may refer to transvaginal ultrasounds as endovaginal ultrasounds.

Sonographers perform this type of fetal ultrasound test internally. They insert a transducer into the vagina that sends out sound waves and produces detailed images of the pelvic region.

Typically, sonographers carry our transvaginal ultrasounds during the first trimester. Medical professionals may recommend transvaginal ultrasounds if a transabdominal ultrasound scan is insufficient.

Transabdominal ultrasound

Transabdominal fetal ultrasound involves the sonographer moving a transducer over the abdomen.

According to a 2020 study, transabdominal ultrasound is a less invasive way of viewing the abdominal organs and fetal development than transvaginal ultrasound.

Ultrasound machines have various modalities that allow them to perform different functions, including:

  • 3D ultrasound: 3D ultrasounds use high-frequency sound waves to detect a growing fetus. Some healthcare providers use them to detect anomalies in the womb.
  • Doppler ultrasound: A Doppler ultrasound focuses sound waves on slight changes in motion. Sonographers can use a doppler ultrasound to get information about the blood circulation of a baby.
  • Fetal echocardiography: Fetal echocardiography produces a distinct image of the fetus’s heart, allowing doctors and other specialists to identify potential heart problems.

Some people choose to have a fetal ultrasound so that they can see an image of the baby.

Other people have a sonogram to:

  • confirm the pregnancy and the baby’s sex
  • check the baby’s heartbeat
  • examine the womb for any fetal abnormalities
  • check for any issues with the placenta
  • examine the condition of the pelvic region

According to March of Dimes, ultrasounds are safe, convenient, and painless. Because they use sound waves, not ionizing radiation, ultrasounds do not affect the fetus.

A professional sonographer must carry out the ultrasound, as complications can arise if untrained people carry out scans.

Sonographers carry out fetal ultrasound scans to ensure the safety of the pregnant person and fetus. Sonograms can also detect if there are abnormalities that require medical attention.

There are different ways to prepare for a sonogram.

For instance, during the first trimester, most people will have a transvaginal ultrasound. This requires an empty bladder to help the sonographer form a clear image of the fetus.

Conversely, transabdominal ultrasounds require a full bladder. This may require a person to drink lots of water before the exam.

For all ultrasound exams during the second and third trimesters, sonographers prefer an empty bladder.

A person having a fetal ultrasound will lie on an examination bed. The sonographer will apply a water-based lubricant gel on the abdomen or in the vagina, depending on the type of scan they are doing. The gel helps the sound waves to travel through the body.

The sonographer will then place a transducer on the abdomen and move it round to capture images on the ultrasound video screen.

Sometimes, the ultrasound technician may measure the images on the screen depending on the purpose of the scan.

If the captured images are clear, the sonographer will clean off the gel, and the person is then free to go. If the sonogram is not clear, the sonographer can perform further scans.

Baby sonograms are one of the most common, safe, and convenient ways to view a growing fetus.

Sonograms allow people to see the moving fetus. However, sonograms show much more than just movement; they provide information about the development of the fetus and the health of the pregnancy and help identify issues that may require treatment.

Always visit a trained sonographer for fetal ultrasounds to avoid any complications.