Prenatal ultrasound scans utilize high-frequency sound waves to create detailed images of your body’s interior, offering a non-invasive and safe method for medical examination. Obstetricians and gynecologists (OBGYNs) often employ these ultrasounds to monitor the development of babies within the womb.
The terms “ultrasound scans” and “sonograms” are sometimes used interchangeably, but it’s important to note the distinction. The prenatal ultrasound scan is the procedure itself, while the sonogram refers to the resulting image.
How Prenatal Ultrasounds Operate
Prenatal ultrasounds rely on the principle of sound wave reflection. When sound waves encounter dense surfaces, they bounce back, with the degree of reflection varying based on density. This rebound, or echo, is translated into varying shades of gray on the sonogram. For instance, if your gallbladder is free of stones, sound waves easily pass through soft tissues and fluids. However, the presence of a stone causes sound waves to bounce back, making them visible to your physician. Advancements in technology have even enabled the creation of 3-D ultrasound images.
What to Anticipate During Your Ultrasound
During a prenatal ultrasound, a sonographer will apply gel to your abdomen before commencing the examination. Using a transducer, which resembles a microphone, they will gently glide it across your skin. The transducer emits high-frequency sound waves, which are translated into an ultrasound image displayed on a video screen.
Typically, doctors conduct an ultrasound around the 20-week mark of pregnancy. This scan serves to confirm the health of the placenta and ensure the baby’s proper growth in the uterus. Additionally, it allows you to witness the baby’s heartbeat, movements, and the development of its body, limbs, and major anatomical features. Depending on the baby’s position, the sonographer may even determine the baby’s gender if you wish to know in advance, though it’s important to remember that ultrasound gender determination is not foolproof.
Preparing for Your Prenatal Ultrasound
No special preparation is required for an ultrasound test. Wear comfortable clothing and be prepared to remove any jewelry and clothing from the waist down. Some doctors may advise drinking 4-6 glasses of water before the test to ensure a full bladder, which can enhance visibility during the ultrasound. While ultrasounds are generally painless and safe, a full bladder might cause slight discomfort.
Most ultrasound exams conclude within 30 minutes, after which you may dress and await the sonographer’s review of the images. Following the ultrasound, you can immediately resume your normal activities.
