Why is my ultrasound not clear?

There are several reasons why your ultrasound image might not be clear. The two most common culprits, particularly in obstetric ultrasounds, are fetal position and difficulty with visualization.

Here's a more detailed breakdown:

• Poor Fetal Position:

  • If the baby is in an awkward position, certain structures can be difficult to see clearly. For instance, if the baby is facing away from the ultrasound probe, it may be harder to get a good view of the face or spine.
  • As the reference indicates, a less-than-ideal fetal position is a common enough issue that a repeat scan is often necessary. One study showed this to be around 4% in non-obese women.
  • Solution: Often, the technician will ask you to move around to try and encourage the baby to shift position. A follow-up appointment might be scheduled if the initial scan is inadequate.

• Poor Ultrasonic Visualization:

  • This refers to factors that prevent the sound waves from penetrating and returning clearly. Several elements can contribute to this:

    • Body Habitus: Excess tissue (particularly abdominal fat) can impede the passage of sound waves, resulting in a less clear image.
    • Scar Tissue: Prior surgeries can create scar tissue that distorts ultrasound waves.
    • Bowel Gas: Gas in the intestines can interfere with the image quality.
    • Insufficient Bladder Filling (for early pregnancy scans): A full bladder acts as an "acoustic window" allowing better visualization of the uterus.

  • Solutions:

    • Drinking water: For transabdominal ultrasounds, drinking water beforehand can help improve visualization (especially in early pregnancy).
    • Transvaginal ultrasound: If a transabdominal ultrasound is unclear, a transvaginal ultrasound might be recommended. This allows the probe to be closer to the area of interest, improving image quality.

In summary, a blurry ultrasound can arise from issues related to the baby's position, or factors hindering the transmission and reception of ultrasound waves. Usually, the sonographer will try to address these issues during the scan or schedule a follow-up if needed.