Understanding the first trimester ultrasound

What You'll Learn From Your First Ultrasound

With your first baby, you may be unsure of what to expect from your first ultrasound. Here's some insight to help you understand the process.

First trimester ultrasound

When you're pregnant with your first baby, you're probably pretty excited about having your first ultrasound but perhaps a bit nervous too, since you're not sure what to expect. Here, we walk you through what you'll learn in this first ultrasound appointment, so you can go in with some understanding (which may ease any jitters too).

What the ultrasound appointment will be like

The ultrasound will take about 10 minutes. You'll usually be asked to arrive at your appointment with a full bladder, and as you've likely seen in movies, the doctor will put some gel on your belly and move a device over it to get a view of your baby.

Your first ultrasound will help date how many weeks pregnant you are

When you're about 10 to 14 weeks pregnant, your first ultrasound will help determine more precisely how many weeks along you are. From this, the due date can be estimated. While using the first day of your last period is one way to calculate your due date, an ultrasound is more accurate.

The ultrasound helps determine your due date based on the size of your baby. Your baby's crown rump length will be taken; this is the baby's length from head to bottom. If your baby measures 3 centimetres, you're 10 weeks along; if the baby's 7 centimetres, you're 13 weeks along.

The doctor will check the baby's heartbeat

At this ultrasound, your doctor will listen to know that the baby's heart is beating and that development is as it should be. While you will be able to make out the baby's head and limbs, it's too early for your doctor to tell if anything abnormal is occurring in the baby's development. However, if Down's syndrome is a concern, it could be tested for fairly accurately through a procedure called nuchal translucency ultrasound.

You'll find out if there's more than one baby in your womb

During the first ultrasound, you'll discover if you're carrying twins, triplets or more babies. If you are having multiple babies, it's good to know at this stage so you can prepare for them, your delivery, your life at home and more.