Understanding Ultrasound Abbreviations in Pregnancy

, Staff Writer
Updated March 6, 2020
Woman doctor giving ultrasound to patient
    Woman doctor giving ultrasound to patient
    Ariel Skelley / DigitalVision / Getty Images

Pregnancy can be complicated, but you can make sure your ultrasound doesn’t have to be. Rather than wonder what "HD" or "EDD" means, gain an understanding of common ultrasound abbreviations used during pregnancy. You’ll also find out why ultrasound biometry is important and the different types of pregnancy ultrasounds available.

Understanding Ultrasound Term Abbreviations

When it comes to an ultrasound of your budding baby, there are quite a few abbreviations you might come across. These are typically used by sonographers and OB-GYNs to track the health and growth of a baby as well as to detect any abnormalities. This works to make sure that everything in the pregnancy is going according to plan.

A few ultrasound abbreviations you might encounter include:

  • AC - Abdominal circumference; a measurement of the abdomen in millimeters, one of four basic measures used to measure a baby’s size and gestational age
  • AF - Amniotic fluid; the fluid that surrounds the baby
  • BPD - Biparietal diameter; measures the diameter of the baby's skull, another basic measure with AC, FL and HC to find age and weight
  • CPR - Cerebroplacental ratio; used in later pregnancies to predict adverse pregnancy outcomes like placental insufficiency
  • CRL - Crown-rump length; a measurement of the fetus from the top of the head to below the butt, which helps to determine gestational age
  • EDD - Estimated date of delivery; the estimated date, based on size and gestational age, for your delivery
  • EFW - Estimated fetal weight; estimated weight of the baby using the basic measurements
  • FHM - Fetal heart movements; a measurement of the heart beat of the fetus
  • FL - Femur length; the measurement of the femur bone, one of the basic measurements taken by the sonographer
  • GA - Gestational age; approximate age of the baby based on the last menstrual period and measurements
  • GS - Gestational sac; one of the first measurements that can be taken with an ultrasound, the sac and fluid that surrounds the fetus
  • HC - Head circumference; measurement around the baby's head in millimeters, a basic measurement used with BPD, FL and AC
  • LMP - Last menstrual period; beginning date of your last menstrual period, used to estimate the date of conception and estimated delivery date
  • MSD: Mean gestation sac diameter; measurement of the gestational sac for aging purposes
  • SGA - Small for gestational age; used when baby is measuring smaller than usual for pregnancy weeks
  • TVS - Transvaginal scan; a pelvic ultrasound done through the vagina, typically shows early pregnancies

Type of Ultrasound Abbreviations

When it comes to ultrasounds, there isn’t just one type that is available to expecting mothers. Most of the time, you’ll get a 2D ultrasound. However, both 3D and 4D ultrasounds are available. Each ultrasound technique adds a new dimension. Learn what the abbreviations stand for and how they are different.

  • A 2D ultrasound is the standard diagnostic tool used to measure and diagnose potential defects or issues. It creates a flat, two-dimensional image as the sound waves bounce off the fetus.
  • A 3D ultrasound creates a three-dimensional image of the budding baby. This allows parents to see their child’s features in more detail. While a 3D ultrasound can be used for diagnostic issues like a cleft lip, it’s typically used for keepsake purposes.
  • A 4D ultrasound creates a live motion video. This means that you get to watch your child move within the womb. The fourth dimension is time, because it is a video and not just a still image. Much like the 3D ultrasound, a 4D ultrasound is typically used as a keepsake.

Ultrasound Biometrics

Taking measurements of your baby during your pregnancy is normal. You’ll typically have about three ultrasounds completed as part of your pregnancy. These typically start around 14 weeks and continue into the 2nd trimester. Pregnancies that are higher risk will get more ultrasound examinations.

Knowing Ultrasound Lingo

When you get your ultrasound images or if you look at your chart, you might see a few abbreviations. Knowing what these sonography abbreviations mean is important. Now that you’ve explored ultrasound abbreviations, you might want to check out examples of ultrasound terminology and the meanings of prescription abbreviations. You can never be too knowledgeable when it comes to your baby’s health.