Sonograms VS Ultrasounds: How Are They Different?

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April 17, 2018

It’s easy to get confused when your doctor uses the words ultrasound and sonogram interchangeably during your prenatal checkup.

Most women, especially those who are pregnant for the first time, find themselves wondering why in the world their obstetrician tells them that they will need an ultrasound one second and then reminds them to go in for their sonogram (not ultrasound) before they leave the office.

Though the words ultrasound and sonogram are often used interchangeably in everyday speech, they’re actually two very different things.

What’s The Difference Between An Ultrasound And A Sonogram?

An ultrasound is the actual procedure in which the ultrasound technician scans your belly with a device called a Doppler in order to gather information about what’s really going on inside.

A sonogram, on the other hand, is simply the term used to describe the picture that is generated due to this ultrasound technique. This sonogram can also be called a scan or an echogram.

So, even though your doctor may say you have a sonogram tomorrow, they really mean ‘you have an ultrasound tomorrow which will produce a sonogram for me to evaluate’.

As you can see, it’s much easier to just say sonogram.

Key Differences

  • Ultrasounds are the technique in which sound waves are used to gather images from inside one’s body
  • Sonograms are the images produced by ultrasounds

How Do Ultrasounds Work?

Ultrasounds use a fascinating technology to gather the information from inside your womb.

When you were in school you probably learned about echolocation; the technique that bats and dolphins use to get around and ‘see’.

Well, ultrasounds work in a very similar manner.

Ultrasounds basically use sound waves which we can’t hear since they’re at such a high frequency.

The frequency of these sound waves is incredibly high but the wavelengths are much shorter than ordinary sound waves.

This short wavelength enables these sound waves to bounce off of objects very easily and therefore, they are phenomenal at displaying detailed images.

Why Don’t Doctors Use X-Rays or CT scans to See the Fetus?

You are probably well aware that ultrasounds are not the only method available to see inside a person’s body.

There are many other options available such as X-rays and CT scans.

So, why do doctors never recommend these methods to check up on the innocent fetus dozing inside of you?

The answer to this is rather simple.

Ultrasounds are the least invasive technology that can check inside one’s body.

X-rays and CT scans use radiation to get the job done, and radiation can be very harmful to the fetus or even harmful to you, especially during these fragile 9 months.

What Are Ultrasounds Used For?

You may very well know how ultrasounds are used to see your developing fetus, but you’re probably wondering what exactly it is that obstetricians can figure out by looking at pictures of your fetus.

By looking at the sonograms produced from your ultrasound procedure, obstetricians are actually able to determine a variety of factors, including:

  • The estimated gestational age
  • The size of the fetus
  • The size and position of the placenta (your baby’s organ of support)
  • Potential abnormalities in the fetus
  • Amniotic fluid levels

Ultrasounds are essential parts of a complicated pregnancy and can act as a source of support and reassurance for obstetricians and soon-to-be mothers alike.

How Often Can I Get An Ultrasound When Pregnant?

Ultrasounds are usually scheduled between 1-3 times during a normal pregnancy.

There are no exact dates in which ultrasounds are required, but obstetricians will probably book you an ultrasound in your first and second trimester to ensure the proper growth of the fetus.

1) First Trimester

Your doctor schedules the first trimester ultrasound (between 1-12 weeks) probably looking to check the gestational age of the fetus, or in other words, to see how many days the fetus has been developing since it was conceived in the first place.

Knowing the gestational age will allow the doctor to accurately predict a delivery date.

Apart from the age, the number of fetuses (whether you’re having one child, twins or triplets!) is usually determined in this first ultrasound.

Chromosome abnormalities and the potential for certain abnormalities such as Down syndrome or diseases which affect the brain and spinal cord can be detected in this first ultrasound as well.

2) Second Trimester

The second-trimester ultrasound (between 12-24 weeks) notoriously known as ‘the gender ultrasound’ will probably have you more excited than the first.

This is the time you actually have a chance of seeing your baby moving around on the screen, and if you’re lucky, you can find out if you’ll be blessed with a little girl or a little boy!

This ultrasound, however, is not specifically done for the purpose of detecting your child’s gender, that’s just a bonus.

The real reason for this ultrasound is basically to check up on the position of your baby, umbilical cord and amniotic fluid levels.

This ultrasound can also help detect serious birth defects.

3) Third Trimester

No matter how smoothly the pregnancy is going, you may find yourself fretting and panicking at the slightest hint of trouble.

This panic usually has a tendency to increase as the days pass and you get closer to giving birth and meeting your child for the first time.

The third trimester ultrasound usually never happens in a normal pregnancy, but if it does, it’s just to check up on the well-being of the tiny human being inside of you, or perhaps to check on amniotic fluid levels.

It’s not uncommon for women to panic in the third trimester and request additional ultrasounds because they haven’t felt their baby move in a few hours, only to find out that everything was okay and their baby was simply having a lazy day.

Parenthood … am I right?

Are Ultrasounds Always Accurate In Predicting Gender?

Though ultrasounds will be mostly accurate, especially when the gender is predicted after 12 weeks, they are still not 100% accurate.

This is why experienced obstetricians will tell you to wait until delivery before you buy your little one’s gender-specific wardrobe!

There are many cases each year where pregnant women are told they will have a girl but they give birth to a boy and vice versa.

Determining the gender really depends on the position of the fetus and how much it has developed.

If the fetus is willing to lay in the correct position and not with its legs curled up then it can be quite easy to determine its gender.

However, if the fetus is lying curled up tight, there isn’t much for a sonographer to work with.

It’s important to note that many medical institutes dislike informing parents about the gender of the child simply because the information is not always 100% accurate and it can lead to more problems down the road.

Can Baby Feel The Ultrasound?

One of your biggest concerns about getting an ultrasound is probably your fear the fetus will feel or even hear the ultrasound and get disturbed.

We would love to give a definite answer on this, but the science on this is conflicting.

Some studies show that ultrasounds can increase amniotic fluid levels as high as 4 degrees, (when the ultrasound happens for extended periods of time and at higher intensities) and the fetus can even hear the ultrasound and it sounds like a ‘screeching subway’.

Naturally, this probably horrifies you, but you should rest assured that as of this writing, these claims have not been backed up properly and therefore they are not openly accepted as scientific facts.

How Will The Ultrasound Be Delivered?

Your pregnancy ultrasound will most likely be a traditional 2D ultrasound.

You will be asked to get into a gown through which the ultrasound technician has easy access to your growing belly.

The technician will apply a gel onto your stomach and then use a Doppler (device that looks and feels sort of like a deodorant with the lid on gliding over your stomach) and begin poking and prodding your belly until they have all the desired pictures.

The pictures will be coming up on a monitor and you can see them yourself as well.

If the technician is unable to get clear pictures, you may be called in for other versions of ultrasounds – which we’ll be discussing in the following list.

1) Transvaginal Ultrasound

Most women dread hearing the words ‘transvaginal ultrasound’ and unfortunately it is as intruding as it sounds.

Transvaginal ultrasounds give the sonographer a much clearer picture of everything going on inside.

The procedure involves inserting a probe into the vagina and the images are taken through this probe.

Transvaginal ultrasounds are usually only done in the first trimester when it is difficult to gather clear images due to the size of the fetus.

2) 3D Ultrasound

3D ultrasounds create a much clearer, and more – you guessed it – 3 dimensional image of the fetus, giving doctors valuable information on the height, width and depth of the fetus and its organs.

3D ultrasounds are given the traditional way, in which gel is placed on your lower belly and a Doppler is used to gather images.

However, the only difference is that more specialized equipment is used during the procedure, and you probably have to see a specialist in the field.

Not every sonographer is equipped with the skills to run a 3D ultrasound.

3) Fetal Echocardiography

Fetal Echocardiography is not done in every pregnancy but may be recommended if your obstetrician has reason to be concerned.

Fetal echocardiography is basically an ultrasound that is dedicated to the fetal heart, where different images of the heart are taken to determine if there is anything out of place.

This procedure is not done by an ordinary sonographer, but rather by an experienced pediatric cardiologist.

Can I Talk To The Sonographer During The Ultrasound?

When going in for an ultrasound you will most likely have butterflies in your stomach and may be incredibly excited to see your baby on screen.

However, the experience may not be as exciting as you anticipated, and if your sonographer is having particular difficulty gathering the images – then it may be a solemnly boring experience.

Most soon-to-be moms are bursting with questions and it’s perfectly okay to ask the technician what they’re seeing and if everything looks alright to them.

Every ultrasound technician is different and they may be open to your questions, or they may be so into their work that they don’t have any time to respond.

Whatever the case is, don’t take it personally and try your best to enjoy yourself and relax as much as possible.

How Do I Prepare?

Having a full bladder for the ultrasound is probably the only preparation that needs to be made beforehand.

Having a full bladder is not necessary, but it can help create a clearer image for sure.

When the bladder is full, the uterus is pushed up and the bowels move down, and this will allow the sonographer to gather clearer pictures.

Drinking three full glasses before coming in for the fetal photo shoot is a good idea.

What About Ultrasound Photo Shoots (4D)?

On the topic of fetal photo shoots, is it a good idea to go in for an actual 4D fetal photo shoot?

Self-selected 4D photo shoots are on the rise and many couples are actively looking for and paying private companies to conduct entire 4D photo shoots and filming sessions for their nearly developed fetus.

Unfortunately, exploiting pregnancy is a multi-million dollar business and 4D photo shoots are a large part of it.

The problem with 3D and 4D photo shoots is that parents are choosing to invade their fetus’ private lifestyle for absolutely no real reason.

The medical community agrees that 3D and 4D ultrasounds are just extra and do not hold any real place for prenatal care.

Another thing is that the services that offer 4D photo shoots are usually private and therefore no one can have any real assurance of how regulated their sonography practices are.

Seeing your baby kick and move is great entertainment, but that’s all it is, simply a fun way to pass time.

There are no proven risks to getting this sort of recreational ultrasound but it really is better to be safe than sorry!

Can Ultrasounds Be Dangerous or Harmful?

Prenatal ultrasounds do not have any known negative effects, especially if they are carried out using legislated methods and techniques.

No studies have been able to successfully prove that a normal ultrasound can harm a baby or cause pregnancy complications.

This makes sense because an ultrasound is simply just sound waves bouncing off of the fetus and no radiation is involved whatsoever.

However, ultrasounds can be dangerous if they heat your tissue above 4 degrees Celsius.

Typical 2D ultrasounds only heat the tissue roughly 1 degrees so there is really nothing to be concerned about.

Can I Opt-Out of Getting a Prenatal Ultrasound?

If for some reason you still feel like you would rather not have your fetus looked at and your belly poked and probed, then by all means, go ahead and discuss your concerns and feelings with your medical practitioner.

Obstetricians will never recommend an ultrasound unless they find it necessary or if they are concerned about your well being or that of your baby.

It is often necessary to have an ultrasound to check on the amniotic fluid levels and to determine a more accurate delivery date.

These things are essential to find out, and if your obstetrician is saying that you need an ultrasound for your own safety then it’s best to listen to them.

Are Ultrasounds Only Used For Pregnancy?

Not only pregnant women have to undergo ultrasounds. Ultrasounds are great for giving detailed images of whatever is happening inside the body and since they don’t use harmful radiation, they are used in a variety of circumstances:

  • Musculoskeletal scans (Shoulders, hips, elbows, breasts)
  • Abdominal Scans (Gallbladder, kidney, liver, etc.)
  • Pelvic Scans( Used to locate cysts in the pelvic area)

It is interesting to note that ultrasound waves travel best through solid materials and that’s why they do not produce good images in areas full of air such as the stomach.

Is It Easy Being A Sonographer?

As you lay on the table and wait for the sonographer, ultrasonographer, or ultrasound technician (whichever you prefer, really) to finish up with your fetus, you may begin wondering about how qualified they are.

(Trust me, some ultrasounds can take a while, especially if the fetus refuses to cooperate).

Sonographers get their well-paying jobs by completing either an associate’s degree, bachelor’s degree, or sometimes even a master’s degree in an area revolving around Sonography.

By well paying, we’re talking roughly $65,000 a year.

After they complete their degree, they have to get licensed for their region and then they are usually good to go ahead and start practicing in a clinic.

Ultrasounds give your prenatal healthcare providers a method of evaluating what’s going on inside your womb.

The sonogram – or pictures produced during an ultrasound procedure – provides a wealth of information on your fetus, placenta, and amniotic fluid.

Ultrasounds use sound waves to gather information and therefore have no known health risks, especially if they are administered in an appropriate manner.

Getting an ultrasound is incredibly exciting because it allows you to see your little one for the first time and gives you peace of mind and reassurance that everything is running smoothly inside.

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2 thoughts on “Sonograms VS Ultrasounds: How Are They Different?”

  1. Avatar

    Thanks for mentioning how ultrasounds will be able to detect any possible abnormalities of the fetus in the womb. My daughter is expecting her first child. The couple wants to be as safe as possible going into pregnancy, so I will be sure to advise them to take the ultrasounds as soon as they can to catch any potential issues early.

  2. Avatar

    That’s good to know that when you get an ultrasound that it’ll most likely be 2D and that when it is happening that you can actually see the images on the monitor yourself. I just found that I’m pregnant so I wanted to learn more about how an ultrasound would work. This makes me wonder if there are 3D ultrasounds since I’d love to see how that would look and if I could get one when my baby gets bigger.

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