At 7 weeks pregnant, an ultrasound scan can usually show your baby’s heartbeat for the first time as a small, steady flicker. For many parents this is the moment the pregnancy starts to feel real. This guide explains what a 7 week ultrasound shows, how big your baby is, what happens if the heartbeat can’t be seen yet, and when to get help.
What does a 7 week ultrasound show?
At 7 weeks, a scan is looking for the early signs that a pregnancy is developing in the right place and as expected. The sonographer will usually look for:
- The pregnancy sac (gestational sac), and that it is inside the womb
- The yolk sac, a small circle that feeds the embryo in the first weeks
- The embryo (sometimes called the fetal pole), which is measured from head to bottom
- The heartbeat, seen as a flicker and often measured in beats per minute
- How many babies there are, as twins can usually be seen by this stage
How big is your baby at 7 weeks?
At 7 weeks your baby is roughly 1cm long, about the size of a blueberry. On the scan, the sonographer measures the embryo from head to bottom. This is called the crown-rump length (CRL), and it is the most accurate way to date a pregnancy at this stage. If your dates from your last period don’t match the measurement, the scan date is usually the more reliable one, because ovulation doesn’t always happen on day 14.
Can you see a heartbeat at 7 weeks?
In most pregnancies, yes. By 7 weeks the heartbeat can usually be seen on an internal (transvaginal) scan. On a scan over the tummy it can be harder to see, especially if your dates are earlier than you think.
If the heartbeat can’t be seen, it doesn’t automatically mean something is wrong. The most common reason is that the pregnancy is earlier than expected. National guidance from NICE is that when the embryo is still small and no heartbeat is seen, a second scan should be done at least 7 days later before any conclusions are drawn. We’ll explain what we see and help you arrange a follow-up scan if you need one.
Will a 7 week scan be internal or over the tummy?
At 7 weeks, an internal (transvaginal) scan gives the clearest pictures because the probe sits closer to the womb. It is safe in pregnancy and is only done with your agreement. If you’d prefer not to have an internal scan, we can scan over the tummy instead. For this you’ll need a comfortably full bladder: drink about 0.5 litres of water 30 to 45 minutes before your appointment.
Why have a scan at 7 weeks?
- You want reassurance that the pregnancy is developing and has a heartbeat
- You’ve had a miscarriage or an ectopic pregnancy before
- You’re not sure of your dates and want a more accurate due date
- Your pregnancy followed fertility treatment
- Twins run in your family
Read our guides to the 6 weeks pregnant ultrasound and the 8 weeks pregnant ultrasound to see how things change week by week.
What you might be feeling at 7 weeks
Many people feel sick, tired and emotional at 7 weeks, and need to wee more often. Sore breasts and a heightened sense of smell are common too. The NHS week-by-week guide has more on what is normal at this stage.
When to get help urgently
Light spotting can happen in early pregnancy, and our guide to bleeding in early pregnancy explains the common causes. But some symptoms can be a sign of an ectopic pregnancy or a miscarriage and need urgent care, not a private scan. Contact your early pregnancy unit, call 111, or go to A&E if you have:
- heavy bleeding
- severe pain, especially on one side of your tummy
- pain in the tip of your shoulder
- dizziness or fainting
Your 7 week scan at The Scan Clinic
Our private early pregnancy scan can be done from 6 weeks at our East London clinic, 6 days a week. No GP referral is needed. You’ll see your baby on a large screen, we explain what we see as we scan, and you’ll leave with your report and 2 scan images.
