Private Dating Scan in London
An accurate gestational age and estimated due date measured from the baby, not from a calendar — explained on screen as we scan, by the sonographer scanning you.
- 30-minute appointment — unhurried, where most clinics allow 20
- Dating from crown-rump length — the most accurate method available
- Findings explained during the scan, before you leave
- Written report usually with you within two hours
- No GP referral required — report and images included
CQC-registered clinic · Provider ID 1-2775844974 · HCPC-registered sonographers
Booking scan, dating scan — what is the difference?
They are largely the same measurement under different names. The NHS calls its first scan a booking or dating scan, and it establishes how many weeks along you are, whether there is more than one baby, and where the placenta lies. A private dating scan answers the same core question — gestational age — on your timetable rather than the hospital’s.
What it is not is NHS combined screening. That assessment, which screens for chromosomal conditions using a nuchal measurement alongside a blood test, is arranged through your midwife at around 12 weeks. We do not provide it, and a private dating scan neither replaces it nor affects your place in that pathway.
How dating actually works
Dating in the first trimester uses crown-rump length — the measurement from the top of the baby’s head to the bottom of the torso. Early on, babies grow at a remarkably consistent rate, so that single length converts to gestational age with real precision.
It is more reliable than counting from a last period, and considerably more reliable if your cycles are long, irregular, or you were not certain of dates to begin with. That is why a scan date will override your own calculation, and why your maternity team will use it going forward.
Accuracy falls as pregnancy advances, because babies begin to vary in size. Beyond around 14 weeks, dating moves to head and femur measurements and becomes less precise — so if dating is your question, earlier is better.
- You want dates confirmed before the NHS scan
- Your cycles are irregular or you are unsure of your last period
- You conceived while using contraception or shortly after stopping it
- You are travelling and need dates confirmed
- You want reassurance in the gap between early scan and 12 weeks
- A previous scan gave dates you want checked
- Gestational age from crown-rump length
- Estimated due date
- Fetal heartbeat and rate
- Number of babies, and membrane arrangement in twins
- Basic assessment appropriate to the stage
- The ovaries and womb
Severe one-sided abdominal or pelvic pain, heavy bleeding, shoulder-tip pain, faintness or collapse need same-day assessment — contact your nearest Early Pregnancy Unit, call NHS 111, or go to A&E rather than waiting for a booked scan.
Is a dating scan right for me?
A dating scan is a good fit if any of these sound like you:
- ✓You are between 8 and 14 weeks and want accurate dates
- ✓Your last period is uncertain or your cycles are irregular
- ✓You want to know how many babies there are
- ✓You want reassurance while waiting for the NHS scan
- ✓You need dates confirmed for travel or work planning
- ✓You are already past your early scan and want the next checkpoint
And when it is not the right booking
You are under 8 weeks — an early pregnancy scan is the better fit, and cheaper.
You want chromosomal screening — NHS combined screening at around 12 weeks goes through your midwife. We do not provide it, and booking with us does not affect it.
You want the anomaly scan or a bonding scan — the 20-week anomaly scan is an NHS pathway scan, and we do not offer bonding scans. Every scan here answers a clinical question.
If another scan would serve you better, we will say so before you book — not after.
What happens on the day
- 1
Arrive with a comfortably full bladderIt lifts the womb into view and usually means the whole scan can be done abdominally. Nothing to fast for. The appointment is 30 minutes.
- 2
We check your dates with you firstYour last period, cycle length and any earlier scan. It matters, because the point of this appointment is to compare your dates against the measurement.
- 3
The scanWarm gel over the lower abdomen. If the view is limited — which happens early in this window — a transvaginal scan may give a clearer measurement. We explain why first, a female chaperone is present, and you may decline.
- 4
The measurementCrown-rump length taken carefully, more than once, and converted to gestational age and an estimated due date.
- 5
Explained as we goYou see the measurement being taken and what it means for your dates, during the scan rather than in a letter afterwards.
- 6
Your report and imagesUsually with you within two hours, with images included, ready to share with your midwife.
Why dating is done when it is
The window is narrow for a reason, and it explains most of what people find confusing about due dates.
Why early dating is precise
In the first trimester babies grow at a strikingly uniform rate. That consistency is what allows one measurement — crown-rump length — to give gestational age to within a few days.
Why it drifts later
From the second trimester onwards, genetics and growth patterns make babies differ in size. Dating then relies on head and femur measurements and carries a wider margin, which is why dates are set early and not revised.
Why the scan date wins
If the scan and your own calculation disagree, the scan is generally the more accurate of the two — particularly with irregular cycles. Your maternity team will date the pregnancy from it.
What the scan may show
Two things we will not sell you. We will not tell you the sex at a dating scan — it is too early to be reliable, and guessing helps nobody. And we do not offer bonding scans: every scan here has to answer a clinical question. If you want to know the sex, that is a gender scan from 16 weeks.
Dates measured, not counted
A 30-minute appointment between 8 and 14 weeks, explained on screen as we scan, with your report and images usually within two hours.
How we run dating scans
Scanned by the person explaining it
The sonographer performing your scan talks you through it and writes your report.
Thirty minutes, not twenty
Time to check your dates properly and answer what you actually came in with.
We will not guess
If a measurement is not clear enough to be relied on, we say so rather than round it into a number.
Alongside the NHS, never instead
Booking privately does not affect your NHS scans or your place in the screening pathway.
Dating scans — your questions answered
When should I have a dating scan?
Is a dating scan the same as the NHS booking scan?
Will a private scan affect my NHS care?
What if the scan gives different dates from mine?
Do I need a full bladder?
Will I need an internal scan?
Can you tell me the sex?
How accurate is the due date?
Can I bring someone with me?
When will I get my report?
Other pregnancy scans we offer
From six weeks — location, heartbeat and how many.
See the scan →
GenderGender Scan
From 16 weeks, when the view is reliable enough to be sure.
See the scan →
GrowthGrowth Scan
Growth, fluid and blood flow assessed later in pregnancy.
See the scan →
Unsure of your dates? Try our pregnancy calculators, or read about coping with scanxiety.
Where can you get a dating scan in London?
Our clinic is at 5a Lucerne Mews, Kensington, London W8 4ED — a quiet mews three minutes on foot from Notting Hill Gate, serving Kensington, Notting Hill, Holland Park, Bayswater and central London.
Short-notice appointments are often available. Call 0203 051 6506 for today’s availability.
Getting here
By tube: Notting Hill Gate — three minutes’ walk.
By bus: Routes along Notting Hill Gate and Kensington Church Street stop nearby.
By car: On-street parking nearby — full options in directions & parking.
Know exactly how far along you are
Crown-rump length measured properly, dates and due date explained on screen as we scan, with your report and images usually within two hours for your midwife.
Kensington, London W8 4ED
3 mins from Notting Hill Gate
Written and clinically reviewed by the HCPC-registered sonographers who perform this scan at IUS London — a CQC-registered diagnostic ultrasound clinic (Provider ID 1-2775844974). Your own findings are explained to you at the scan and set out in your report.
Author: Yianni Kiromitis, Senior Sonographer, HCPC RA38415 — over 20 years’ experience in NHS and private ultrasound · Reviewed 10 August 2026