Fetal Ultrasound-20 week ultrasound

In Canada, a fetal ultrasound is offered around 20 weeks to assess for fetal abnormalities.  Some woman are also offered a dating ultrasound early on to determine gestational age and give an estimated due date.

The ultrasound assesses the baby, placenta and cervix for size, location, position and also assesses the development of various organs.  The test also checks for markers, which are NOT abnormalities but can be associated with some chromosomal problems (mainly Down syndrome and Trisomy 18).  The finding of a marker is used to adjust your base risk for Down syndrome or Trisomy 18.  It does NOT mean that your baby will definitely be born with Down Syndrome or Trisomy 18!!

Many parents will worry if their ultrasounds come back with the presence of soft markers.  I know, I was once there too-

Like most moms, I was so excited to go to my 20 week ultrasound.  I had this date scheduled in my calendar for weeks and hubby took the day off to go with me. I was going to find out the gender of my baby, and officially start my baby gear shopping spree!

I was told to drink 4 tall glasses of water, and to finish them 1.5 hours prior to the exam.  Nope, not gonna happen.  I’ve had an ultrasound done before, and I knew drinking 4 tall glasses of water is just going to make me pee my pants. Not to mention, it would likely make me throw up .  So I cheated, and only drank 2.

By the time I got to the ultrasound, I already needed to pee. Really bad.  Fortunately, the technician was able to see my full bladder, and let me go PARTIALLY empty my bladder 15 minutes into the exam.  (You mean to stop peeing mid-stream?! Are you kidding me?!)

The technician was really quiet throughout the exam.  I couldn’t see what she was looking at, and I guess she could sense I was getting anxious.  She told me not to worry, everything looked okay.  She also told me, she’s pretty sure I was going to have a girl! I knew it! I knew I was having a girl. I was absolutely thrilled beyond belief.

At the end of the exam, she took my ultrasound to get them verified by the doctor.  She was gone for a really long time.  I thought something was wrong, but then she came back and told me I could leave. I specifically asked her if something was wrong, she tells me no.

 A couple of weeks later, my doctor calls me to tell me to come in to “review my ultrasound results”.  My heart sank.

Turned out, there were a couple of markers on my ultrasound.

She proceeds to tell me that my baby had a thickened nuchal fold, and an echogenic foci. I had no idea what this even meant, and neither did my hubby, but at that moment I thought my life was over.  She then tells me she’s going to refer me to see another doctor who specialized in genetics and that she would recommend another detailed ultrasound along with an amniocentesis.

In the days that followed, I was worried sick.  I researched these terms, what it meant in terms of the risks, and I asked many people for their opinions.  I searched the forums extensively for other mom’s going through the same thing, but no one had stories of having the same markers as I had.  I took comfort in the stories of other mom’s who had perfectly healthy babies despite having soft markers.  Deep down, I felt that nothing was wrong.  Yet I was still worried.

A thickened nuchal fold is a soft marker for chromosomal abnormalities like Down’s syndrome.  The nuchal skin fold is “the distance between the bone of the back of the head, and the overlying skin”.  (San Diego Perinatal Centre )

A thickened nuchal fold will increase a mother’s base risk for Down’s by a factor of 17.

The other marker I was told is an echogenic foci.  Essentially, this is seen as a dot in the heart that is as bright or brighter than bone.  This marker is considered to be a low risk marker, and increases the base risk by a factor of 2.

While we were waiting to go in for our detailed ultrasound, my hubby and I had a thorough discussion of “what if?”

It’s difficult for any soon- to- be -parent to have this discussion.  For us, we realized right away that we were far too attached to the baby already to even consider abortion.  We decided that, unless the baby has an abnormality that would cause her to be born stillborn, we would not consider terminating the pregnancy.  This is, obviously, a very personal decision.

By the time my detailed ultrasound day came around, we were quite calm.  As I laid on the exam table, I could see my baby happily kicking my cervix, raising her hands to wave at me, rubbing her eyes, and bouncing up and down.  After an agonizing amount of time, the doctor finally tells me “I don’t see any markers.”  Huh? He proceeds to tell me that yes, the nuchal fold is thickened but it isn’t thickened enough to be a worry.  It is still within normal.  I breathed a sigh of relief…and the echogenic foci? He felt the foci isn’t brighter than bone.  I cried tears of joy.  He tells me if I want to, I can still get an amniocentesis to verify (since an amniocentesis is the only thing that can definitively say whether baby had an abnormality or not).  Poke a needle inside my perfectly health womb? NO WAY!

Needless to say, my baby is a perfectly healthy baby girl.  Perhaps next time…I may decline to do ultrasounds altogether to avoid the distress of any potential “problems”.

If you’ve been told that your baby has some soft markers, a good resource can be found at the SOGC Clinical Practice GuidelinesBabyCentre.ca also has a very good explanation of ultrasound soft markers.

Unfortunately, many parents will stress over the presence of markers.  It’s important to remember that even though it does increase your risk for Down’s or Trisomy 18, many, many babies are still born healthy despite having markers.

You might find this calculator helpful in calculator your risk:

Have you ever been told you had a marker? Please share your story! 

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