Published on September 1st, 2021 and Updated on January 14th, 2025
Check out SneakPeek Gender Test to determine your baby’s gender!

Your pregnancy may have started with an easy-to-take at-home pregnancy test, but after receiving your B+ result (B+ for baby positive, that is), your doctor will run you through a gamut of other exams to check your baby’s development and ensure a healthy delivery. One test in particular you may be looking forward to is your first pregnancy ultrasound.
As you prepare for your first ultrasound appointment, you’re likely to have a lot of questions, including:
Is sonogram the same as ultrasound?
Although the terms ultrasound and sonogram are often used interchangeably, they are actually not the same. A sonogram is the image produced by an ultrasound—a procedure which uses high-frequency sound waves to show internal organs and tissues (as well as your growing baby).
In this article, we’ll take a closer look at sonograms and ultrasounds to ensure you have an A+ understanding of them. So grab your pen and notebook, and let’s get started.
Defining Sonograms and Ultrasounds
Put simply, a sonogram refers to an image, while an ultrasound refers to a procedure. Although not the same, these terms are often used interchangeably because they’re both aspects of a pregnancy ultrasound. In fact, in order to have a sonogram, you first need to have an ultrasound.
To better understand the difference between sonograms and ultrasounds, let’s break down what defines each:
- Ultrasound – An ultrasound is a medical procedure that uses high-frequency sound waves to create visual images of internal organs and tissues. These sound waves bounce off of internal structures, making echoes that are then translated into visual images by a computer. Ultrasounds are a type of diagnostic imaging that have been used since the 1950s for various medical purposes, including to examine a woman’s womb and her growing baby during pregnancy.
- Sonogram – A sonogram is the visual image produced by the ultrasound procedure. Sonograms are typically black and white, with solid whites representing hard tissues (such as bones), grays representing soft tissues (such as tendons and muscles), and blacks representing fluid (for instance, the fluid found in your amniotic sac). By studying a pregnancy sonogram, a trained medical professional can learn information about a growing baby and track development.
Other helpful terms to note include:
- Sonography – The practice of performing an ultrasound with an ultrasound machine.
- Sonographer – A medical professional who’s trained to operate ultrasound equipment. A sonographer may also be referred to as an ultrasound technician.
What happens during a pregnancy ultrasound?
There are two different types of pregnancy ultrasounds: transvaginal ultrasounds and transabdominal ultrasounds. Each type of fetal ultrasound produces a sonogram that’s then given to a radiologist who’s been specially trained to analyze sonograms. The radiologist will work together with your doctor to review the sonogram and interpret the results.
Transvaginal Ultrasounds
Transvaginal ultrasounds are most commonly used in early pregnancy ultrasounds, which can occur anywhere between 6 and 8 weeks into pregnancy. At this early stage of pregnancy, the uterus and fetus are still rather small. In fact, at 6 weeks, your baby is only the size of a pea (a little sweet pea).
To see a clear image of your tiny little pea, as well as your uterus, ovaries, fallopian tubes, and cervix, your doctor will recommend a transvaginal ultrasound. This is because, in the early stages of pregnancy, the baby, uterus, ovaries, and fallopian tubes will still be situated deep inside your pelvis, making them harder to detect with a transabdominal ultrasound. As your pregnancy progress and your baby grows, your uterus will grow too, expanding up and out until it no longer fits inside your pelvis.
To perform a transvaginal ultrasound, your sonographer will insert a probe-shaped ultrasound wand, also known as an ultrasound transducer probe, a few inches into the vagina. While this process isn’t painful, some women may experience slight pressure.
The transducer then emits high-frequency ultrasound waves which bounce off the internal organs and structures to create a sonogram (a visual image) of your baby and reproductive system on a video monitor. With the sonogram, your doctor will be able to:
- Confirm the pregnancy
- Check for an ectopic pregnancy or cysts
- Detect the fetal heartbeat
- Estimate your baby’s due date
- Examine the cervix and placenta
- Assess the uterine lining
Overall, the entire procedure takes about 30 to 60 minutes.
Transabdominal Ultrasounds
After about 8 weeks, your uterus and baby will have grown large enough to expand past your pelvis, resting closer to your belly button and making it possible for your doctor to perform a transabdominal ultrasound. This type of fetal ultrasound sends sound waves from atop the belly, rather than from inside the vagina.
To perform a transabdominal ultrasound, your ultrasound technician will first apply ultrasound gel to the tip of the ultrasound wand. This is done because ultrasound waves travel better through liquid than air. The ultrasound gel, therefore, acts as a layer of liquid between the wand and your abdomen as the sonographer rubs the transducer across your belly, which produces the sonogram on a video monitor. A transabdominal ultrasound scan is completely painless, but the tickling sensation of the wand gliding across your stomach may cause a few giggles.
Depending on the stage of pregnancy in which a transabdominal ultrasound is performed, your doctor will be able to:
- Examine your baby’s heart, brain, kidneys, and liver
- Check for chromosomal or facial abnormalities
- Measure the length of your baby
- Monitor your baby’s heart rate
- Determine your baby’s gender
If you’re carrying one baby, a transabdominal ultrasound will typically last about 30 to 60 minutes. However, for those expecting twins, triplets, or more, additional time will be needed to thoroughly examine each baby.
What will your sonogram look like?
The specific information you’ll learn from your prenatal ultrasound and the visuals you’ll see in your sonogram will depend on what stage of pregnancy you’re in, and what time of ultrasound you’re having. So, when do you get your first ultrasound?
Early Pregnancy Ultrasounds
Early pregnancy ultrasounds are often recommended if your pregnancy is considered high-risk by your doctor. This may be the case if:
- You’re experiencing bleeding or abdominal pain
- You’re 35 or older
- You have a history of miscarriage or pregnancy complications
- You suffer from certain medical conditions, such as high blood pressure or diabetes
With early pregnancy ultrasounds, your doctor can examine the condition of your reproductive organs and monitor your baby’s initial development to ensure you and your baby are healthy and to stay on top of any potential complications.
Because these ultrasounds take place early in pregnancy, a sonogram will only show the beginnings of your amniotic sac (which will look like a black blob on your sonogram) and potentially, the fetal pole—the first image of your baby, also referred to as the embryo.
At 8 weeks pregnant ultrasound, the fetal pole will appear as a gray blip within the black amniotic sac, measuring approximately 14mm in length.
Nuchal Translucency Ultrasounds
Nuchal translucency ultrasounds are performed during optional nuchal translucency (NT) screenings between weeks 11 and 13 of pregnancy. Although NT screenings are beneficial for all pregnant women, they’re highly recommended for women who have a family history of birth defects, as they can help determine the likelihood of chromosomal abnormalities, including Down syndrome.
At this stage of your pregnancy, a sonogram will show a more clearly defined image of your baby, with an easily identifiable head. Your baby will also have grown significantly since week 8, measuring between 45 to 84 mm from the top of the head to the bottom of the torso.
Anatomy Ultrasounds
During the anatomy ultrasound scan, which typically takes place between weeks 18 and 20, your doctor will measure and examine your baby’s major organs. In particular, your doctor will look at the brain, heart, liver, and kidneys to ensure they’re developing properly. With this second trimester ultrasound, your doctor will also be able to determine the gender of your baby with 99% accuracy.
The anatomy ultrasound sonogram is likely the sonogram you’re most looking forward to seeing. At this stage of pregnancy, your baby will have grown too big to measure from top to bottom in one sonogram image. Instead, you’ll receive individual sonograms showing your baby’s head, face profile, abdomen, hands, and feet.
3-D and 4-D Ultrasounds
3-D and 4-D ultrasounds are like traditional ultrasounds in that they use high-frequency sound waves to produce a sonogram of your growing baby. However, these ultrasounds also use specialized imaging software that allows the sonogram to show sharper, more detailed 3-D visuals. With 4-D ultrasounds, the sonogram actually acts as a video, showing your baby’s movement inside the womb.
Although these types of ultrasounds are generally not medically necessary, some doctors may perform them to help diagnose potential birth defects, such as cleft lips or cleft palates. But more often than not, 3-D and 4-D ultrasounds are requested by expectant parents who want a more detailed keepsake sonogram. While many commercial centers offer these types of ultrasounds, it’s safer for you and your baby to only receive these ultrasounds if they’re performed by your doctor.
How to Prepare for an Ultrasound
Before you ask how much does an ultrasound cost, there are things you need to prepare first. Regardless of which type of ultrasound you’re receiving, your doctor can let you know the best way to prepare for your appointment. In earlier stages of pregnancy, your doctor may request you arrive at your appointment with a full bladder or partially full bladder, as ultrasound waves travel better through liquid.
Other ways you can prepare for a pregnancy ultrasound appointment include:
- Reaching out to your health insurance company to confirm what costs (if any) you’re responsible for paying. While many health insurance companies cover medically necessary ultrasounds, you may still be responsible for your copay or deductible.
- Ensuring you have the proper insurance information on hand, as well as your ID.
- Confirming with your doctor how many guests (if any) can be in the room with you during the procedure.
- Choosing an outfit that’s easy to remove (for a transvaginal ultrasound) or an outfit that allows easy access to your stomach (for a transabdominal ultrasound).
- Avoiding large meals beforehand, as a full stomach may cause discomfort during the procedure.
Bond with Your Baby Before Your Ultrasound Using SneakPeek
Having an ultrasound marks a truly life-changing moment in your pregnancy journey. Hearing your baby’s heartbeat, receiving a sonogram to take home with you, and learning the gender of your little one only strengthens the bond you share.
So why wait for your first pregnancy ultrasound to get to know your little prince or princess?
With SneakPeek’s At-Home Early Gender Prediction Test, you can learn your baby’s gender as early as 6 weeks into your pregnancy. Plus, the test is easy to take and provides clinically-proven over 99% accurate1 results.
A picture of your baby may be worth a thousand words, but to discover your baby’s gender, you only need one. Find out yours sooner, with SneakPeek.
Editorial Policy
At SneakPeek, our commitment is to provide accurate, up-to-date, and reliable information to empower our readers. Our content is thoroughly researched, reviewed by medical experts, and fact-checked to ensure its credibility. We prioritize the well-being and education of our readers, and our editorial policy adheres to the highest standards of integrity and accuracy in all our articles.
This post has been reviewed for accuracy by the following medical professional:
Katie Smith is a seasoned Certified Nurse Midwife and a nurturing mother to six children, offering a unique blend of professional expertise and personal experience. She is the founder of Birth Your Way Midwifery and Women’s Wellness Center in Bay County, Florida. Katie's comprehensive approach to care is informed by her hands-on experience in motherhood and her passion for empowering women through their birthing journey. Her dedication extends beyond her center as she actively engages in community wellness and family health education.
Sources:
- The Bump. Sonogram vs. Ultrasound: What’s the Difference? https://www.thebump.com/a/sonogram-vs-ultrasound
- Health Images. Sonogram vs. Ultrasound. https://www.healthimages.com/sonogram-vs-ultrasound/
- Very Well Family. Transvaginal Ultrasound During Pregnancy. ??https://www.verywellfamily.com/ultrasound-in-early-pregnancy-2760113
- What to Expect. 6 Weeks Pregnant. https://www.whattoexpect.com/pregnancy/week-by-week/week-6.aspx
- Ultrasoundpaedia. FIRST TRIMESTER ULTRASOUND – Normal. https://www.ultrasoundpaedia.com/normal-1sttrimester/
- Parents. Pregnancy Ultrasounds Week by Week. https://www.parents.com/pregnancy/stages/ultrasound/ultrasound-a-trimester-by-trimester-guide/
- Radiopaedia. 11-13 week antenatal scan. https://radiopaedia.org/articles/11-13-week-antenatal-scan?lang=us
- NCBI. The accuracy of 2D ultrasound prenatal sex determination. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3530251/
- Parents. What Is a 3D Ultrasound? https://www.parents.com/pregnancy/stages/will-i-need-a-3d-ultrasound/