The 11-14 Week Scan

All women booked at UCLH will be offered a scan between 11 and 14 weeks of pregnancy. 

The main reasons are: 

To date the pregnancy

This is particularly relevant for women who cannot remember the date of their last period, have an irregular cycle, or who have conceived while breastfeeding or soon after stopping the pill. By measuring the crown-rump length (CRL) of the baby, the gestational age and therefore expected date of delivery can be calculated. 

To diagnose multiple pregnancy

Approximately 2% of natural conceptions and 10% of assisted conceptions result in multiple pregnancy.  

To assess the chance of Down’s syndrome and other chromosomal abnormalities 

All women, irrespective of their age, have a chance of having a baby with a chromosomal abnormality such as Down’s syndrome, Edward’s syndrome or Patau’s syndrome. Across the UK, it is recommended that the Combined Test (looking at a part of the baby’s neck on scan and a blood test) should be offered, which you can read about more here. 

The results of this test take about two hours after your scan. You have the choice of either waiting in the hospital for your result, or we can contact you later in the day either by your MyCare app or by telephone.  

If the test results show you have a high chance of your baby having a chromosomal abnormality, we will discuss the next steps of testing available to you. 

To assess the chance of pre-eclampsia

Pre-eclampsia is a pregnancy complication in which you develop high blood pressure, protein in your urine and often problems with your placenta. This can lead to slowing of the growth of your baby and often premature birth. 

This problem occurs in around 1 in 50 women. The majorities of pregnancies developing these problems have a good outcome. However, in a few cases, pre-eclampsia can be dangerous for both mother and baby, so identifying it early is key to avoiding harm. 

At UCLH, we offer an extra test at the 11-14 week scan which assess your chance of developing pre-eclampsia, by taking into account: 

• Your medical and family history. 
• Your blood pressure.  
• The blood flow in the vessels that supply blood to the uterus and the placenta. 
• The level of PAPP-A (a hormone produced by the placenta) in your blood (the same hormone measured as part of the Down’s syndrome screening test).  

If this test shows your are of a high chance of developing pre-eclampsia, we will offer you closer monitoring in pregnancy and often recommend that you start taking aspirin. Please discuss this with your healthcare provider. 

To identify early problems with the pregnancy

The 11-14 week scan is an opportunity to check the pregnancy is developing normally, which means very sadly we occasionally found that the baby has died or has a major problem. Both of these are rare (less than 3%), but we will offer support and counselling on the next steps to couples. 

If we find something wrong, you will be given an opportunity to see our specialist teams in the early pregnancy unit or fetal medicine unit who can discuss the findings with you in more detail. 

You will be welcomed into a scan room in the Antenatal Clinic, which will usually have one or two people who will do your scan (called ultrasonographers). During your scan, we will offer: 

• To take your blood pressure. 
• To calculate your BMI, using your height and weight. 
• To take a blood sample from you. 
• To review your medical history, including previous pregnancies. 
• To do a scan of your tummy (abdominal scan). 

Sometimes, we will offer to do a scan from inside your vagina in order to get better views of the baby, or to check the neck of the womb.

There is no evidence that having a scan in pregnancy is unsafe to you and your baby. 

You can say no at any time during your maternity care – having a scan and any of the screening offered alongside, is a choice. If you do not feel comfortable with your options, ask your midwife to be referred for a discussion with a senior midwife or doctor. You will then be supported to find an option that works for you. 

You do not need to have a full bladder before your scan. You are more than welcome to bring someone else with you. We understand that sometimes you need to bring young children with you, but please be mindful that the ultrasonographers need some level of quietness to concentrate when scanning.  

If possible, please try to avoid using any creams on your abdomen for 24 hours before your scan, as they can occasionally interfere with our machines. If you have any concerns about this, please speak to your midwife. 

We do our best to provide women with a photo of their baby as a keepsake, but this is dependent on the position of the baby and availability of our resources. You are able to use your phone to take photos throughout the scan, but please discuss this with the sonographer in the room.

NHS Screening Tests 

Screening for Down's syndrome, Edwards' syndrome and Patau's syndrome - NHS

Screening tests for you and your baby: easy guides - GOV.UK 

Screening tests for you and your baby - GOV.UK

Antenatal Results and Choices (ARC) – non-directive information and support before, during and after antenatal screening

Downs Syndrome Association

Sands | Saving babies' lives. Supporting bereaved families. 

Twins Trust - We support twins, triplets and more... 

UCLH - Screening tests

UCLH cannot accept responsibility for information provided by other organisations.  

Maternity Direct Line: 020 344 79400 

Switchboard: 020 3456 7890 

Email: uclh.obstetricscanqueries@nhs.net  

We will endeavour to reply to your email within five working days. 

Website: www.uclh.nhs.uk