Arriving and getting comfortable
There is no special preparation for this scan. When you arrive we will welcome you, confirm your details and pregnancy history, and explain what the examination involves so you know exactly what to expect.
Anomaly Scan at the London Pregnancy Clinic
Our private anomaly scan perfectly complements your NHS scan, with a more extensive checklist. Usually performed at 20-25 weeks of pregnancy.
The NHS 20-week scan is part of the Fetal Anomaly Screening Programme (FASP), which looks for 11 physical conditions — our scan checks for these and many more.
Available atLPC City (E1)LPC West (SW10)
What is an anomaly scan?
An anomaly scan is a detailed ultrasound examination of your baby's anatomy, carried out in the middle of pregnancy. Working carefully from head to toe, it checks how each part of your baby is growing and developing. You may also hear it called the mid-pregnancy scan, the 20-week scan or the anatomy scan.
Its purpose is both reassurance and, where it is needed, early information. Most pregnancies are entirely healthy, yet a congenital anomaly is diagnosed in around 1 in 43 pregnancies in England, according to national NCARDRS figures. Finding a difference before birth means your care can be planned calmly and in good time, with the right specialists involved.
When everything looks as expected, the scan offers real peace of mind.
At the London Pregnancy Clinic, every anomaly scan is performed by GMC-registered fetal medicine doctors and HCPC-registered specialist sonographers, using high-resolution ultrasound equipment and working through an extended checklist that covers more structures than a routine screening scan — with unhurried time to answer your questions.
The anomaly scan at a glance
A few figures that put the mid-pregnancy scan in context. These reflect the NHS screening programme; our private anomaly scan covers the same anatomy with an extended checklist.
18–21 weeks when the NHS offers the anomaly scan (NHS)
~30 minutes how long the NHS screening scan usually takes (NHS)
~1 in 43 births in England where a congenital anomaly is diagnosed (NCARDRS, 2021)
The most detailed examination of the Fetal Anatomy
The ultimate detailed ultrasound scan of the fetal anatomy. It takes a close look of your baby, including an extensive checklist of the internal organs and structures, with special attention to the heart and brain.
Most extensive checklist of fetal anomalies
By 20 weeks of pregnancy, you are roughly halfway through your journey. This is an ideal time to re-examine the anatomical development of your baby using our anomaly scan in London. More specifically, we recommend the London Pregnancy Clinic scan to be performed at 22 weeks, when the major structures of the baby’s brain are completely developed.
The mid pregnancy scan involves a thorough examination of the fetal anatomy including a top-to-toe examination of the baby and its environment in the womb. Whilst checking your baby, we have the most comprehensive list of organs and structures that we examine, paying special attention to the fetal brain and heart defects. Read more about fetal anomalies and rare diseases and when they can be screened for using ultrasound.
The NHS provide a free screening programme, performed by specially trained sonographers, for fetal anomalies in mid-pregnancy (the anomaly scan). Please visit the NHS page for more information.
Wondering how the two fit together? See our side-by-side guide: private vs NHS anomaly scan. For what the NHS scan itself looks for and what happens on the day, read our guide to the 20-week anomaly scan.
When is the best time for an anomaly scan?
The NHS offers its screening scan between 18 and 21 weeks. At the London Pregnancy Clinic we usually suggest booking a little later — at around 21 to 22 weeks — for the reasons explained above.
The scan suits any pregnancy, whether or not you have already had an NHS scan. Many parents choose it as a thorough complement to their NHS care, for a second opinion, or simply for extra reassurance and unhurried time to ask questions. It can be especially valuable if an earlier scan raised a query, if there is a family history of a heart or genetic condition, or if you would like a more detailed look than a routine appointment allows.
Our anomaly scan complements rather than replaces your NHS appointments, and because some conditions only become visible later in pregnancy, a follow-up scan in the third trimester can be worthwhile — the FAQs below cover both in more detail.
Choose our Anomaly Scan
- We perform meticulous top-to-toe screening tests of the fetus and check more structures than any other institution,
- We perform an advanced fetal heart examination for every baby we scan,
- Our anomaly scan in pregnancy is scheduled at a slightly later gestational age (preferable 21-22 weeks) because some important structures of the brain are not completely developed at 19 weeks, which is when the majority of the NHS scans are performed,
- We check the corpus callosum, an important midline structure of the brain, which is challenging to examine,
- We have immense experience in screening for fetal anomalies,
- On your clinician request we can perform a doppler examination of your uterine arteries blood flow and/or cervical length measurements (no add-on fee for the test),
- We use the most advanced ultrasound scanners equipped by state-of-the-art high-resolution probes,
- We have the latest 3D/4D technology available to our healthcare professionals (quality of image depends on general resolution of the scan and can sometimes be low before 25-26 weeks),
- We provide you with your black and white images and videos, which can be downloaded by you from our secure cloud server.
What happens during your anomaly scan
A systematic head-to-toe survey
Most of the scan is carried out gently over your abdomen with a little warm gel. Your GMC-registered fetal medicine doctor or HCPC-registered specialist sonographer works methodically from head to toe, taking careful measurements and pausing so you can watch your baby on the screen.
Checking your baby's environment
We also look at the position of the placenta and the amount of fluid around your baby. If your baby is lying awkwardly for a particular view, we may suggest a short break or a gentle change of position, then try again.
Your report and images
The clinician who performed your scan talks you through the findings on the day, and you leave with a written report and images of your baby. There is always time to ask about anything you would like to understand better.
Understanding your results
In the great majority of cases the anomaly scan is reassuring, showing a baby whose anatomy is developing as expected. Your report summarises what was seen, your baby's measurements and the position of the placenta.
Sometimes a scan notes a 'soft marker' — a minor finding that is common in healthy babies and, on its own, rarely signifies a problem. Where a marker or a possible difference is seen, the clinician who performed your scan explains what it means, how likely it is to matter and what sensible next steps might be. This is a conversation, not a diagnosis, and you will never be left to interpret a result on your own.
Depending on what is found, next steps might include a repeat scan, a detailed fetal cardiac scan, non-invasive prenatal testing such as NIPT, or referral for specialist fetal medicine advice. No single scan can rule out every condition, which is why blood-based screening and later scans remain valuable. If anything ever worries you about your pregnancy or your baby's wellbeing, your midwife or maternity unit is there for you at any time.
Do you have any specific requests for your anomaly scan?
Talk to our team about anything you would like us to focus on during your scan. Call us on 020 3687 2939, message us on WhatsApp (+44 7305 175116), or book your anomaly scan online.
Plan your next step
You have a question? We have an answer.
The NHS also provides an anomaly scan for every pregnant woman. Why should we get this scan at London Pregnancy Clinic?
The NHS provide a free screening programme, performed by specially trained sonographers, for fetal anomalies in mid-pregnancy (the anomaly scan).
Please visit the NHS page for more information.
How is the Anomaly Scan performed?
Most of the time, a fetal anomaly scan is performed transabdominally; however, in a small number of cases, when the baby is in an awkward position and does not wish to move, we may need to perform a transvaginal scan (TVS, internal scan) to check the lowest part of the baby. Similarly, if the placenta is low or praevia (covering the birth canal), we may also need to do a TVS.
You do NOT need to have a full bladder for the scan. We want you to feel comfortable!
Can we exclude all anomalies or genetic syndromes using this scan?
Unfortunately, there is no test that can diagnose or exclude all fetal anomalies or diseases.
The anomaly scan can detect the majority of fetal anomalies, while some (up to 25% of all anomalies according to new research) are not visible or not developed at 20-23 weeks. As a result, those would go undiagnosed. Fortunately, the majority of those anomalies are mild and treatable after birth, although some of them, such as brain anomalies and tumours can be very serious.
Therefore, because the anomaly scan cannot exclude all anomalies with late manifestation and there is no routine scan after 20 weeks on the NHS, we strongly recommend having a follow-up by the 3rd trimester anomaly scan at 28 weeks.
Unfortunately, some chromosomal or genetic conditions have no ultrasound features and therefore are not detectable by ultrasound at any stage of gestation.
Can you exclude Down’s syndrome by Anomaly Scan?
Definitely not! Some of the babies with Down’s syndrome have no features on the ultrasound and will have a normal appearance on the anomaly scan.
Currently the best screening test for Down’s syndrome is NIPT. You can have the NIPT add-on for your anomaly scan (requires additional payment for the blood test).
Learn more about our harmony test or invitae NIPT options.
What is placenta previa?
Placenta praevia is a pregnancy complication where the placenta develops in the lower part of the uterus, partially or completely covering the cervix (the opening to the birth canal). The main symptom is painless vaginal bleeding, typically occurring after 20 weeks of pregnancy, though some women may experience no symptoms at all. Risk factors include previous caesarean sections, multiple pregnancies, maternal age over 35, and smoking during pregnancy.
The condition is typically diagnosed during routine ultrasound scans and requires careful monitoring throughout pregnancy. Treatment often involves hospital admission if bleeding occurs, bed rest, and restricted activity. In most cases, a caesarean section delivery is necessary to ensure the safety of both mother and baby. With proper medical care, most women with placenta praevia have successful pregnancies, though they may need extended hospital stays and careful post-operative care.
Should I still get my NHS Anomaly Scan even after having done one at London Pregnancy Clinic?
Yes, we strongly recommend having your scheduled scans by your NHS provider. It is important for the continuity of prenatal care, as well as for planning your follow-up and delivery.
Can I have my images from the scan? What else will I get?
Yes, of course. We use Tricefy which is a secure cloud system to upload images from your scan to be viewed before you even leave the scanning room! You will also receive a hard and soft copy of your detailed ultrasound report as well as some high-quality colour printouts for you to take home with you.
Tricefy also allows you to download the images from the scan to share with your loved ones via message/social media.
We provide still ultrasound images for you to take away with you on the day. We also send these to you electronically, with a couple of video clips. We provide a USB stick with the full 3D/4D experience.
What does the anomaly scan check for?
The scan is a systematic check of your baby's anatomy — including the brain and spine, the face and lips, the heart and chest, the abdominal wall and organs, the kidneys and bladder, and the arms, legs, hands and feet — along with the placenta and the fluid around your baby.
It covers the 11 physical conditions screened for by the NHS Fetal Anomaly Screening Programme — such as open spina bifida, cleft lip and serious heart conditions — and our extended checklist examines many additional structures. You can read more in our guide to common fetal anomalies.
Can you tell the baby's gender at the anomaly scan?
Often, yes. If you would like to know and your baby is lying in a helpful position, your clinician can usually check the baby's sex during the anomaly scan. It is not the main purpose of the scan, so occasionally the baby's position makes a confident view difficult.
Do let our team know at the start of your appointment whether you would — or would not — like this information included.
Is an ultrasound anomaly scan safe for my baby?
Yes. Ultrasound has been used in pregnancy for decades and is considered safe. As the NHS explains, the sound waves used in ultrasound scans do not involve any radiation, unlike X-rays or CT scans.
The scan is painless, although you may feel light pressure as the probe moves across your abdomen.
How long does an anomaly scan take?
The NHS 20-week screening scan usually takes around 30 minutes, according to the NHS.
Because our anomaly scan works through a more extensive checklist and leaves room for your questions, we set aside an unhurried appointment — please allow a little longer than a routine NHS visit.
What happens if the anomaly scan finds a problem?
Most findings are minor, and many need nothing more than a repeat scan to keep an eye on things. Whatever is seen, the clinician who performed your scan talks it through with you on the day, so you leave understanding your report rather than worrying about it.
If a finding does need further assessment, we explain the options — covered in more detail in the 'Understanding your results' section above — and, with your consent, keep your NHS midwife or maternity team informed so your care continues smoothly.
How much does a private anomaly scan cost?
Our private anomaly scan costs £260. That includes the extended anatomy checklist, your written report on the day, and your images and video clips, which you can download from our secure cloud server.
If your clinician has asked for a doppler examination of the uterine arteries or a cervical length measurement, we can include it during the same appointment at no extra fee. You can book online or call us on 020 3687 2939 if you have any questions first.
Can I bring my partner to the anomaly scan?
Yes. You are very welcome to bring your partner, a family member or a friend to share the moment with you. If you have any questions about who can join you at your appointment, just call our team beforehand.
What is a soft marker, and what happens if one is found?
A soft marker is a minor finding on the scan that is usually a normal variant, but which has historically been associated with a slightly higher chance of a chromosomal condition. Most babies with an isolated soft marker are entirely healthy.
The ones we are most often asked about are an echogenic intracardiac focus — a bright spot in the heart, sometimes called a golf ball — a choroid plexus cyst in the brain, and echogenic bowel. Each page explains what the finding means on its own, what it does not mean, and when it is worth looking further.
What if the fluid spaces in my baby's brain measure wide?
The fluid spaces in the brain (the ventricles) are measured at every anomaly scan. A measurement of 10mm or more is called ventriculomegaly, and in its mild, isolated form the outlook is usually reassuring.
Our ventriculomegaly page sets out the measurement bands, what "isolated" means and why it matters so much, and what a detailed follow-up scan is looking for.
Can I have my whooping cough vaccine around the time of the anomaly scan?
Yes — the timing lines up well. The whooping cough vaccine is offered from 16 weeks of pregnancy and most women have it at around 20 weeks, so many arrange it in the same week as their anomaly scan. It is free on the NHS through your GP surgery or maternity service.
Our whooping cough vaccine in pregnancy guide explains how mid-pregnancy timing protects your newborn, and we also cover the flu and RSV vaccines offered later in pregnancy.
Contact
Do you want to know more about our anomaly scan?
Sources & clinical references
The figures and clinical statements on this page are drawn from the sources below. Guidance evolves — always discuss your individual circumstances with a clinician.