Pregnancy Ultrasounds Explained
Seeing your baby during pregnancy ultrasounds are some of the most exciting moments for expectant parents as they take a glimpse into their baby’s growth and development in-utero.
Ultrasounds are also valuable tools for medical professionals. They allow for the early detection and diagnosis of many conditions prior to baby’s birth. They also allow your Dr or Midwife to check your baby is growing as expected, monitor your amniotic fluid levels, check your baby’s position with greater accuracy, and establish the location of your placenta (among many other things!).
How do ultrasounds work during pregnancy?
Pregnancy ultrasounds are also known as sonograms. They use high-frequency sound waves (that we cannot hear) to produce images of what is going on inside our bodies. They are performed by an ultrasound technician/sonographer. But if you have an OBGYN caring for you, they may also do these themselves.
Ultrasounds are usually done with an ultrasound wand (called a transducer). The sonographer will place it on your abdomen after applying lubricant. The wand will be pressed onto your belly. Depending on what the sonographer is trying to assess it may be firm or lightly.
Sometimes, an ultrasound needs to be performed inside your vagina, a transvaginal ultrasound. To do this, the sonographer will ask for your consent to insert a small wand inside your vagina. This can be uncomfortable. But it shouldn’t cause you any pain. This kind of ultrasound is more common during the first trimester when baby is tiny as it allows the technician to get a clearer view of a very early pregnancy.
When do pregnancy ultrasounds take place?
You will usually get two to three ultrasounds during your pregnancy. However, it largely depends on where you are based. In Australia and New Zealand, you’re generally offered one around 12 weeks, and one around the halfway mark. Sometimes you’ll also have an early one if you’re not sure about dates. Occasionally if baby needs extra monitoring, you might have extra ultrasound growth scans during your pregnancy
Let’s take a look at some of the common ultrasound appointments and what they are for!
Dating Scan
The pregnancy dating scan is done in the first trimester usually around 8-14 weeks but sometimes earlier depending on when you found out you were expecting! Not everyone needs a dating scan. It’s just helpful for your provider to get an idea on when you might be due because at this gestation, babies typically have similar measurements.
At your dating scan, your Dr will also be looking for a heartbeat – often visible around 5.5-6 weeks. Just so you’re aware – often a transvaginal scan is also needed when it comes to the dating scan to give a better view at this early stage.
Note: you may be instructed to arrive to your first ultrasound with a full bladder – which can be hard for a pregnant woman who is needing to use the bathroom a whole lot more! The reasoning for the full bladder is that it can help to ensure a better view of your uterus.
Early Anatomy/Nuchal
The nuchal scan is usually performed around 12-14 weeks. The sonographer will check your baby’s anatomy to make sure everything is developing as it should. As well as screening for any conditions/chromosomal anomalies (the results of this are combined with a blood test you’ll have done around a week before.) They’ll also check your uterus and ovaries and the location of your placenta.
Morphology
This is done around 19-20 weeks. Again, the sonographer checks everything is measuring as it should and has a thorough look over baby’s organs and placenta, as well as things like amniotic fluid. You can also find out your baby’s gender at this scan if you would like to! For many normal pregnancies, this is the last pregnancy ultrasound you will receive before you meet your baby!
Growth Scans
These are not routinely offered – but some mamas do have extra scans, particularly in the third trimester. This is usually because your pregnancy/baby’s growth needs to be monitored a bit more closely. Reasons for growth ultrasounds may include:
- You have a placenta condition such as placenta previa or accreta.
- Your baby is tracking large for gestational age.
- Your baby isn’t growing as much as anticipated.
- Your fundal measurements aren’t consistent with your baby’s gestation.
- If your cervix needs to be checked regularly (if it is short or thin)
- You are expecting multiple babies.
- A condition was identified earlier in the pregnancy that requires further monitoring.
If you ever have any questions
Please don’t be afraid to ask. The sonographer may be able to tell you what they are able to see. If there are any concerns, these will be followed up quickly by your Dr of Midwife.
Make sure you check out our instagram post: “I’m pregnant when will I have my ultrasounds?” for more information on your upcoming pregnancy ultrasounds.
Pregnant Mamas make sure you check out our FREE Prenatal class that 8 out of 10 new mothers say they wish they took before birth to ease their stress and worries. You can even watch it at your own pace from the comforts of your own home! Sign up here!
It’s important to note that ultrasounds should be discussed with a healthcare provider to ensure safety and suitability for individual circumstances. This blog is general education only. For any personal based advice regarding you or your baby please seek advice from your own healthcare professional.
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