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20-week Anatomy Scan: What and What Not to Expect

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20-week Anatomy Scan

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First of all, congratulations on covering the major milestone of your pregnancy journey! You are halfway through the months of anxiety, exhaustion, and nausea, and it’s time for your big anatomy scan at 20 weeks.

A sonographer will take a few measurements and make sure you and your little human are progressing as you both should be. You will even get to know the sex of the baby at this scan (but of course, it’s up to you if you want to keep that piece of information in suspense).

What’s the best thing to happen at this scan? You get to walk away with some precious pictures of your unborn joy that you can share with family and friends. It will be an exciting day punctuated with stress and nervousness. Want to prepare yourself for the 20- week’s anatomy scan? We have got you covered with this blog on what happens on this big day for you and your baby.

What Does a 20 Weeks Anatomy Scan Look Like?

During your pregnancy, you will be scheduled for an ultrasound in the 20th week of your journey. Sometime between 18 and 22 weeks of gestation, an anatomy scan will be taken to monitor your baby’s changing form. This ultrasound uses high-frequency sound waves to generate pictures of your womb and the baby in it.

Some warm gel is put on an ultrasound wand or a transducer which is moved around your baby bump to evaluate key measurements of your baby’s development and growth. This appointment will also let you know the general size of the baby and whether they are trending small, big, or right on target.

What are The Measurements Taken for a 20-week Anatomy Scan?

The sonographer or ultrasound technician will take some measurements to make sure the little one’s growth is bang on track. Here’s what they measure:

  • Hands
  • Feet
  • Legs
  • Arms
  • Chest
  • Face
  • Genitals
  • Diaphragm
  • Bladder
  • Stomach
  • Kidneys
  • Heart
  • Brain
  • Spine

You can hear the sweet rhythm of your baby’s pitter-patter heartbeat at 120 to 180 beats per minute. Apart from that here’s what the technicians find in a normal healthy baby from an anatomy scan at 20 weeks:

  • The vertebrae of the baby must be aligned and covered with their skin.
  • The umbilical cord will have 3 vessels and meet the abdomen.
  • The placenta will be assessed to rule out placenta previa.
  • They will also ensure that you have amniotic fluid enough to sustain your little swimmer.
  • They will also examine your cervix to check if it’s closed and long. An open or short cervix puts you at risk of premature labor).

How Does a 20-week Anatomy Scan Identify The Baby’s Sex?

During the 20-week anatomy scan, the technician will be able to tell you the baby’s gender. Depending on the baby’s position inside the womb, the ultrasound wand will identify the testicles and penis or clitoris and labia. If you are okay with keeping it as a surprise till the delivery date, then let the technician know that beforehand so they don’t blurt anything out. If your baby is not in the proper position, it will be difficult to determine the sex with absolute certainty.

Can a 20-week Anatomy Scan Identify Abnormalities?

The anatomy scan at 20 weeks is also an opportunity to identify markers or abnormalities for potential disorders like Trisomy 18 and Down syndrome. A combination of ultrasound scanning and blood work from your first trimester must have already provided some information but as the baby gets bigger, it becomes easier to notice abnormalities.

  • A 20-week ultrasound can not only identify genetic defects but also organ abnormalities such as congenital heart defects, or disorders that cause infant death. The technician will carefully examine the 4 chambers of the great and check its functioning to rule out any heart defects.
  • They will also look for fluids in the bladder that points out if the kidneys are working well enough.
  • The spine must also not have any openings at all.
  • They can also identify a cleft lip or a cleft palate during the ultrasound at 20 weeks.

Remember that any potential defects that are identified early on will only help your medical team to develop a plan while birthing and beyond. It can also prepare you emotionally for the unique journey ahead.

Here’s What You Can Expect at a 20-week Anatomy Scan

An anatomy scan at 20 weeks might be exhausting with all that excitement and anticipation. We have curated all the tips to help you be prepared for that appointment you have been waiting for.

  • Plan to Be There for a While

An anatomy scan at 20 weeks is not an in-and-out appointment. You might need to spend at least 45 minutes in the scanning room. So do not schedule the scan around meeting hours or when you are in a rush. The scan time also depends on how active your munchkin is. The baby needs to move and be active to take pictures and take measurements. You might also need to meet your OB-GYN, later on, to discuss how the anatomy scan went. So pre-plan the appointment ahead of time and do not have other commitments right before or after the scan.

  • It Might Take Some Work

Most probably, the sonographer will take some time to measure the baby’s organs and body parts to ensure that the baby is healthy. And if your little one doesn’t feel like showing off their little foot or frontal, you might have to engage in some gymnastics to get the baby in the right position. All this takes time and work.

Furthermore, if you are carrying multiples, you will have to wait till both your adamant little ones show off their respective parts. If they are not active enough you might have to take a walk, drink something, or shift your position so that the babies shift inside you. The tech may also prod or probe your belly and its sides to get the baby to shift its position.

  • You Can Ask for a Break

Making your shy thumb sucker active can get tiring at times. You might have to move around yourself to get your little one moving. It’s OK to pause for a while if getting all the measurements right is taking time. If you need a few minutes or are getting uncomfortable, speak up. Do not shy away from asking for a break because it is a completely understandable situation.

  • You Need to Wait on Answers

Patience is a virtue. The sonographer in attendance might or might not be super chatty during the process because they are really busy. Some might give you updates throughout the process but if they don’t then your doctor will catch up with you after the scan. Technicians may not be allowed to answer certain questions depending on the center’s policy so you gotta wait till you get an answer.

  • Bring a Support Person

Have someone accompany you to the appointment but not a crowd as the whole process could be stressful. You could have a limited number of people depending upon your doctor’s or the medical center’s visitors policy. Check with them before making plans to avoid last-minute confusion because everyone wants to have a sneak peek at the baby. Having a crowd of people around might make you extra nervous because of all the stress of the scan involved. It’s best to have those around whom you are emotionally dependent to support you through the appointment.

  • Expect Unexpected Pictures

There will be pictures but they might not be what you expected so brace yourselves. The quality of these pictures might vary depending on whether they are 2D, 3D, or 4D. 3D or 4D images are quite detailed but taking them requires special types of equipment that may not be available at every clinic. Depending on what they see, the technician will be able to shift from each of these versions.

Your experience of the 20 weeks anatomy scan varies depending on the medical insurance you have and the pieces of equipment the doctor’s office is having. It might be tempting to get a picture-perfect photo of your little one but the American College of Obstetricians and Gynecologists advises against non-medical ultrasounds.

The Bottom Line: 20-week Anatomy Scan

The 20 weeks anatomy scan is the biggest day in the journey of your pregnancy. You will get a glimpse of your munchkin’s precious face, find out if they have any abnormal body features, get updates on their size, and if you want you can know the much-anticipated news of whether it’s a boy or a girl. Remember to prepare for the appointment in advance so that you have enough time on your hands to get the measurements done without errors.

Leave that spot in your nursery or your room for all the ultrasound pictures of squishy cuteness. Make sure you take only medically approved ultrasounds and get the best for your baby.

20-week Anatomy Scan: What and What Not to Expect FAQs

1. What does the 20-week anatomy scan check for?

An ultrasound at the 20th week of pregnancy looks for details in the baby’s anatomy to find any abnormalities whatsoever. The scan check for
  • Abdomen
  • Kidneys
  • Face
  • Spinal cord
  • Brain
  • Heart
  • Bones
  • 2. What birth defects can a 20-week anatomy scan detect?

    The ultrasound scan taken at 20 weeks of pregnancy detects abnormalities in the unborn child. It finds out of the baby has
  • Omphalocele (type of abdominal wall issue)
  • Gastroschisis (intestinal issues)
  • Renal agenesis (missing one or both kidneys)
  • Congenital heart defects
  • Spina bifida
  • Cleft lip
  • Indicators of trisomy 13 and Down’s syndrome or trisomy 18
  • Anencephaly
  • 3. Do they check your cervix at a 20-week anatomy scan?

    During an ultrasound scan at 20 weeks of pregnancy, the sonographer will typically use warm gel on your baby bump and guide the wand around to have a good look at your baby. You can get pictures and measurements at this scan. At this appointment, the sonographer may also take a transvaginal ultrasound with a wand to get a closer look at your cervix.

    4. What can you eat before an anatomy scan?

    Some pregnant women drink a glass of orange juice, have a sugary snack, or munch on some fresh fruits an hour or so before they get an anatomy scan. It is believed that the temporary infusion of sugar in your bloodstream will make the baby move around actively during the ultrasound. However, don’t get sugar-rush with this concept in mind. If your baby is shy during the ultrasound, your sonographer will ask you to switch positions.

    5. Do you need a full bladder for an anatomy scan?

    Generally, you will be asked to drink around a liter of water before you take the scan so that you have a full bladder. A full bladder helps the physician or the sonographer take pictures of the ultrasound.

    6. Can an anatomy scan show Down's syndrome?

    Structural abnormalities may be identified during the 20 weeks anatomy scan. It can detect defects such as
  • Heart abnormalities
  • Urinary defects
  • Body wall abnormalities
  • Significant clubfeet
  • Cleft palate or lip
  • Spinal defects
  • Down’s syndrome
  • Trisomy 18
  • 7. Can autism be detected in an anatomy scan?

    Autism is detected through fetal anomaly ultrasound scans. It has been seen that kids who went on to develop ASD had a greater abdominal and head circumference along with greater cerebellar diameter. This abnormality could be detected at their 20 weeks anatomy scan.

    8. Is the 20 weeks anatomy scan 3D?

    The anatomy scan at 20 weeks can be done in 2D, 3D, and 4D ultrasound. It checks on the progress of the physical development of your baby so that you can rule out any congenital disorders or defects along with any anatomical abnormalities.

    On behalf of the editorial team at Parenthoodbliss, we follow strict reporting guidelines and only use credible sources, along with peer-reviewed studies, academic research institutions, and highly respected health organizations. To learn about how we maintain content accurate and up-to-date by reading our medical review and editorial policy.

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