Everything You Need to Know About Ultrasound Scans in Pregnancy
A calm guide for expectant parents in Bexley, Dartford and the surrounding areas
For many parents, pregnancy scans are one of the most exciting parts of pregnancy. Seeing your baby on the screen, watching their little movements, and hearing that everything looks as expected can feel incredibly reassuring.
But scans can also bring up lots of questions.
What are they looking for?
Are ultrasound scans safe?
What happens if they cannot see everything clearly?
And what if you want an extra scan for reassurance?
This blog explains what ultrasound scans are, what to expect during pregnancy, and what to know about NHS and private scans.
What is an ultrasound scan?
An ultrasound scan uses high-frequency sound waves to create an image of your baby inside the womb.
It does not use radiation. This is an important difference. Ultrasound is not the same as an X-ray or CT scan. X-rays and CT scans use ionising radiation, while ultrasound uses sound waves.
During most pregnancy scans, gel is placed on your tummy and a handheld probe is gently moved over your skin. This probe sends sound waves into the body, which bounce back and create the image you see on the screen.
In very early pregnancy, a transvaginal scan may sometimes be offered. This uses a slim internal probe and can give a clearer picture when the pregnancy is still very small. You should always be asked for consent, and you can ask questions before deciding.
Are pregnancy ultrasound scans safe?
Ultrasound scans have been used in pregnancy care for many years. The NHS says ultrasound scans do not use radiation, and the sound waves used are safe.
Like any part of maternity care, scans should be carried out by trained professionals and used appropriately. The aim is always to gain useful information about your pregnancy and your baby’s wellbeing.
A medical scan is different from having repeated, long scans purely for entertainment. Private scans can be lovely and reassuring, but they should still be carried out by qualified professionals and should never replace NHS maternity care.
How many scans will I be offered on the NHS?
In England, most pregnant people are offered two routine NHS ultrasound scans.
These are:
The dating scan, usually between 11 and 14 weeks
The 20-week screening scan, usually between 18 and 21 weeks
You may be offered extra scans if there is a reason to monitor your pregnancy more closely. This might be because of your medical history, your baby’s growth, the position of the placenta, twins or multiples, or something seen at an earlier scan.
Having extra scans does not automatically mean something is wrong. Sometimes your maternity team simply needs more information.
The dating scan: around 11 to 14 weeks
The first routine scan is often called the dating scan, or the 12-week scan.
This scan helps to:
Check your baby’s heartbeat
Confirm how many weeks pregnant you are
Estimate your due date
Check whether you are carrying more than one baby
Look at early development
Offer screening for Down’s syndrome, Edwards’ syndrome and Patau’s syndrome, if you choose to have it
It is very common for your scan due date to be different from the date you worked out using your last period or a pregnancy app. This does not usually mean anything is wrong. The scan measurement is used because it gives a more accurate estimate of how far along you are.
The scan usually takes around 20 minutes, although this can vary. Sometimes babies are not in the easiest position, and the sonographer may need more time to get the measurements they need.
The 20-week scan: around 18 to 21 weeks
The 20-week scan is also called the anomaly scan or mid-pregnancy scan.
This is a more detailed scan that looks at your baby’s development. The sonographer will check different parts of your baby’s body, including the head, brain, face, spine, heart, stomach, kidneys, arms, legs and feet.
The scan also checks the position of your placenta.
Although many people think of this as the scan where you may be able to find out your baby’s sex, that is not the main purpose of the appointment. The main purpose is to look for certain physical conditions and check your baby’s development.
You may be able to find out if your baby is a boy or girl, depending on your hospital’s policy and your baby’s position, but it is not guaranteed.
It is also important to know that no scan can detect every possible condition. A normal 20-week scan is reassuring, but it does not guarantee that a baby will not have any health conditions.
What if they cannot see everything clearly?
Sometimes a scan cannot be completed because of your baby’s position, the position of the placenta, your gestation, or other factors that affect the view.
This can feel worrying, but it does not always mean there is a problem.
You may be asked to walk around, change position, empty your bladder, or come back another day. Often, the sonographer simply needs a better view.
If there is anything they are concerned about, they should explain what has been seen and what happens next. This may involve another scan, referral to a specialist, or further tests.
Extra scans during pregnancy
Some people are offered additional NHS scans during pregnancy.
These may include:
Growth scans
Placenta location scans
Doppler scans to check blood flow
Presentation scans to check baby’s position
Follow-up scans after an earlier finding
Growth scans are common, especially if there are concerns that baby may be measuring smaller or larger than expected. These scans estimate your baby’s size, but they are not perfect. Measurements can vary, and your maternity team will usually look at the overall pattern rather than one measurement alone.
Private pregnancy scans
Some parents choose to book private scans during pregnancy.
This might be for:
Early reassurance
Seeing baby between NHS appointments
Finding out baby’s sex
3D or 4D bonding scans
Reassurance later in pregnancy
Private scans can be a positive experience for many families, but they should be viewed as an addition to NHS care, not a replacement.
If you have pain, bleeding, reduced baby movements, feel unwell, or feel that something is not right, contact your maternity unit or triage team. Do not rely on a private reassurance scan instead of medical advice.
If you are booking privately, it is sensible to choose a clinic that is clear about who performs the scan, what training they have, whether the clinic is CQC registered, what the scan can and cannot tell you, and what happens if anything unexpected is seen.
Local private scan options: Dartford and Bluewater
For families in Bexley, Dartford, Gravesend, Swanley, Greenhithe and the surrounding areas, there are a couple of local private scan options that parents may come across.
These are not a replacement for NHS maternity care, but they may be helpful if you are looking for extra reassurance, a bonding scan, a gender scan or a 3D/4D scan.
Hey Baby 4D Dartford
Hey Baby 4D Dartford is based in The Orchard Shopping Centre in Dartford.
They offer a range of private scan options at different stages of pregnancy, including early reassurance scans, gender scans, wellbeing scans, 4D baby scans, late reassurance scans and NIPT screening.
Their listed scan options include:
Early Reassurance Scan from 6 to 16 weeks
Wellbeing and Gender Scan from 16 weeks
Wellbeing and 4D Baby Scan from 24 to 34 weeks
Late Reassurance Scan from 16 to 38 weeks
Express Gender Scan from 18 to 38 weeks
NIPT and reassurance scan from 10 weeks
Hey Baby 4D Dartford states that their pregnancy scans are performed by qualified and highly experienced sonographers. Their Dartford clinic is also registered with the Care Quality Commission.
Their clinic is located at:
Hey Baby 4D Dartford
Unit 2, The Orchard Shopping Centre
Dartford
DA1 1DN
Phone: 01322 479939
They also describe the clinic as wheelchair accessible, with space for guests. Their website says families can bring up to three guests, and children are welcome.
My Scan Hub at Bluewater
My Scan Hub is based at Bluewater Shopping Centre in Dartford.
They are a private medical imaging centre offering ultrasound scans, MRI scans and blood tests. Their website describes the clinic as an independent healthcare provider based at Bluewater, with online booking and no GP referral needed for many services.
For pregnancy scans, My Scan Hub offers private pregnancy ultrasound options, including individual pregnancy scans and pregnancy scan packages.
Their website highlights:
Private ultrasound scans at Bluewater Shopping Centre
Same-day appointments, subject to availability
Online booking
No GP referral required for many services
Free parking
Same-floor access
A location around 10 minutes from Dartford and around 15 minutes from Sidcup, Bexley and Swanley
Scan reports and images available securely online
Published pricing, with pregnancy ultrasound options listed from £80
Their clinic is located at:
My Scan Hub
Guildhall Outer Car Park
Bluewater Shopping Centre
Dartford
DA9 9ST
Phone: 0800 151 2227
My Scan Hub may be a useful option for parents who want a private scan in a medical imaging setting, especially if Bluewater is convenient for them.
Things to ask before booking a private scan
Before booking any private scan, it is worth asking:
Who will carry out the scan?
Are they appropriately qualified?
Is the clinic registered with the CQC?
What exactly is included in the appointment?
What happens if they see something unexpected?
Will they refer you back to NHS maternity services if needed?
Is the scan medical, reassurance-based, or mainly for bonding images?
How long will the scan last?
What happens if baby is not in a good position?
A good clinic should be clear about what the scan can and cannot tell you.
Scans are your choice
It is important to remember that screening scans are offered to you. They are your choice.
Some parents want every scan and every piece of information available. Others may feel anxious about screening or unsure whether they want certain information. You are allowed to ask questions, take time to decide, and speak to your midwife about your options.
Your maternity care should continue whatever decisions you make.
Final thoughts
Pregnancy scans can be exciting, emotional and sometimes nerve-wracking. They can provide reassurance, help date your pregnancy, check your baby’s development and give your maternity team important information.
The main things to remember are:
Ultrasound uses sound waves, not radiation
Most people are offered two routine NHS scans
The dating scan is usually between 11 and 14 weeks
The 20-week scan is usually between 18 and 21 weeks
Extra scans may be offered if your team wants to monitor something more closely
Private scans can offer reassurance, but they should not replace NHS care
If you are worried about symptoms, always contact your maternity unit or midwife
At Little Village Antenatal, we believe information should feel clear, calm and easy to understand. The more you know about your pregnancy care, the more confident you can feel asking questions, understanding your options and making decisions that feel right for you.
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View our upcoming course dates and book your place here.
Because the more you know, the calmer you'll be, and the calmer you are, the better labour tends to go.
This blog is for informational purposes only and does not replace the advice of your midwife or maternity team. If you are ever unsure whether you are in labour, or if you have any concerns at all about your health or your baby's wellbeing, always contact your maternity unit or midwife. In an emergency, call 999.