Congratulations, mama. You’re halfway through your pregnancy journey. After months peppered with nausea, exhaustion, and anxiety, you’ve made it to this major milestone.
What’s more, it’s time for your big 20-week ultrasound.
A technician will take some important measurements, make sure everything is progressing as it should, and possibly be able to identify the sex of your growing baby (it is up to you if you want to learn that key piece of information).
Best of all, you’ll likely walk away from the examination table with lots of printed pictures of your precious bundle that you can enjoy and happily share with family and friends.
It’s an exciting experience, but one that’s often punctuated by nerves and stress. It can be a joyous event — but also a worrisome one.
Want to be prepared for everything the 20-week ultrasound will entail? We’ve got your back — and your burgeoning belly — covered.
Scheduled sometime between 18 and 22 weeks of gestation, the 20-week ultrasound is also often referred to as an anatomy scan.
This ultrasound uses high frequency sound waves that generate a moving picture of your internal workings and your baby’s changing form.
An ultrasound technician will gently move a transducer, or ultrasound wand, covered in warm gel around your abdomen to obtain key measurements and evaluate your baby’s growth and development.
You’ll also get a general idea of your baby’s size and whether they’re trending big, small, or right on target.
What measurements are taken?
The ultrasound technician will carefully take measurements to make sure your baby’s growth is on track.
They’ll measure your baby’s:
They’ll also check the spine to ensure that the vertebrae are aligned and entirely covered by your baby’s skin.
During the ultrasound, you’ll get to hear the sweet pitter-patter rhythm of your baby’s heartbeat. A normal heart rate range at this stage of gestation is 120 to 180 beats per minute.
The ultrasound technician will also check the umbilical cord to ensure it meets the abdomen and has three vessels. Your placenta will also have its moment in the spotlight, as the technician assesses any risk of placenta previa.
They will make sure you have adequate amniotic fluid to accommodate your little swimmer.
And finally, they may switch to use a transvaginal ultrasound wand to check that your cervix remains long and closed (if it has shortened and/or opened at all, you may be at greater risk for premature labor).
Identifying the sex of your baby
During the anatomy scan, a technician may also be able to determine the sex of your little one.
Depending on your baby’s position, and their level of cooperation, an ultrasound technician is usually able to identify either a labia and clitoris or a penis and testicles.
Of course, it’s entirely your call if you want to find out based on what’s spotted on the screen. It can be tempting to lose all resolve in the moment, but many soon-to-be parents choose to wait for the big delivery day reveal.
If you plan to keep your baby’s sex a surprise, be sure to let your ultrasound tech know your intention in advance so that they don’t accidentally blurt anything out. (Spoiler alert — it happens!)
It’s also worth noting that there’s always a small margin of potential error in determining sex (talk about a big delivery surprise!).
If your baby doesn’t get into the proper position, it can be more challenging for a technician to make the call with absolute certainty.
What abnormalities can be identified?
The 20-week scan also offers an opportunity to identify certain abnormalities or markers for potential genetic disorders like Down syndrome or Trisomy 18.
The combination blood work and ultrasound screening available in your first trimester may have already provided some information. As the baby gets bigger, though, it becomes easier for a healthcare professional to identify possible issues on screen.
The technician will also be checking for any organ abnormalities.
Since congenital heart defects are one of the most common abnormalities, and a leading cause of infant death, the ultrasound tech will carefully evaluate the four chambers of the heart and check to make sure everything is functioning properly.
They’ll look for fluid in the bladder to make sure kidneys are doing their job and scan the spine for any openings, as well.
A tech may also be able to identify a cleft lip and less frequently, a cleft of the palate during the 20-week ultrasound.
This all may sound very intimidating, and it certainly can make this exciting ultrasound feel slightly more nerve-wracking.
It’s important to remember, however, that identifying any potential abnormalities early on will help you and your medical team develop a plan of action for birth and beyond.
It also can help prepare you mentally and emotionally for the journey ahead.
Plan to be there a while
The 20-week ultrasound is not an in-and-out appointment, so leave yourself plenty of time. Do not schedule it around work meetings or other important obligations.
You could be there for 45 minutes or for well over an hour for your ultrasound.
It often depends on how compliant your little nugget is feeling that day. You may also meet with your doctor after the ultrasound is complete.
It might take some work
It can take time for a technician to get all the measurements they need.
And if baby doesn’t feel like showing off their left foot or giving you and your tech a full frontal, well, you might have to go through some veritable gymnastics to get that little one in the right position.
Furthermore, if you happen to be expecting multiples, you’ll have to repeat the process until both (or all!) of your adamant littles do their respective parts.
Nevertheless, get pumped — you are about to get up close and personal with your baby (or babies)!
If it so happens that your little one is not helping the process move efficiently, the technician might ask you to shift around, take a quick walk, change positions, or drink something to motivate baby.
The tech may gently poke or prod at your belly or side with the wand to try to nudge your babe into place.
Know you can ask for a break
Do not fret if your thumb sucker (you might be able to spot this early habit!) is acting a bit stubborn.
You and your technician will work together and get creative to get the necessary measurements and views. But also know that if it’s taking a while, it’s OK to pause.
If you’re feeling uncomfortable or need a few minutes, just speak up. It’s OK (and completely understandable) if you need a breather or a bathroom break.
You’ll have to wait on answers
The technician may not be super chatty during your appointment — they’re hard at work, after all.
Some may give you some updates throughout the process; others may not. Some may not be allowed to answer certain questions. It all depends on your practice’s policy.
If you’re not getting answers or assurances, a tech will likely have the doctor review the scans and come into the room to speak with you after your ultrasound is complete instead.
Bring a support person — not a crowd
This whole process can be stressful. You may be able to have a partner or support person in the room with you. However, don’t plan on bringing the whole family.
Depending on your hospital, doctor’s office, or medical center’s policy, you could have a limited number of visitors, so check with them before making plans.
Everyone wants a sneak peek of baby, but the main purpose of the visit is information for your doctor. It’s important that you and your tech can get the job done.
There will be pictures — but they might not be what you expect
Speaking of seeing that tiny squirmy worm on screen, you’ll be utterly amazed at seeing your little one on screen, but what you see might vary.
The quality of these pics is very different depending on whether they’re 2D, 3D, or 4D. 3D and 4D ultrasounds offer more detailed images, but they require special equipment and may not be available in all locations.
At your appointment, the tech might be able to switch back and forth between these different versions, depending on what they need to see.
The experience may also vary based on technology available at your doctor’s office and what your specific medical insurance covers.
Some people leave with a perfect 4D image of their baby’s face, but some have to settle for a fuzzy outline of their profile.
While it can be tempting to try for the perfect picture by heading out for a keepsake ultrasound another day, keep in mind that the American College of Obstetricians and Gynecologists discourages parents-to-be from getting non-medical ultrasounds.
The 20-week ultrasound is one of the biggest and most important appointments of your pregnancy.
You’ll get a glimpse of your little one’s precious face, receive an update on their size, find out if everything is functioning and developing properly, and maybe even learn if you’ll be welcoming a son or daughter in a few short months.
Prepare for the appointment in advance.
Decide if you want to know your baby’s sex and leave yourself plenty of cushion time (it can be a waiting game!). And be sure to clear a spot on your refrigerator for a whole roll of adorable ultrasound pictures.
Ah, the squishy cuteness — enjoy!