Screening tests are used to find people who may have a higher chance of a health condition. All pregnant women, and babies will be offered a range of tests throughout the pregnancy, and after birth, for certain conditions. Awareness of these conditions enables us to provide you with the best, early individualised care. Early diagnosis provides more treatment options. All the tests are free and based upon the best clinical evidence available. It is your choice whether you wish to be tested or not.

If you have difficulty reading or writing, please follow this link for easy read guides to screening: Screening tests for you and your baby: easy guides - GOV.UK (www.gov.uk).

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Screening tests allow us to find out if you have a high or low chance of a health problem during your pregnancy.  All pregnant women will have an equal opportunity to be offered a screening test.  This should be done at the earliest opportunity in pregnancy, ideally less than 10 weeks of pregnancy.

Your midwife will discuss the range of screening options available at your first appointment and signpost you to the online information “Screening tests for you and your baby”.

A copy of the booklet is available to download in a variety of languages – click here

At your booking appointment the midwife will offer you the following blood tests:

Full blood count

To check your iron levels, platelets and white blood cells.

Blood group and antibodies screen

This will confirm your blood group and check if you have any abnormal antibodies.  Antibodies are your body’s natural defence against anything which is
different from yourself. For example, a virus, vaccine or a different blood
group. They are part of your immune system and protect your body against
harmful invasions like infections.  Not all antibodies are harmful to the pregnancy.  The midwife or doctor will discuss the changes to your pregnancy based on antibody results.

Haemoglobinopathies

This will check if you are a carrier for inherited conditions such as Sickle Cell or Thalassaemia. If your tests show that you are a carrier for one of these conditions, screening can be arranged for the baby’s biological father to help in the assessment of the risk of your baby being affected by one of these conditions. We can also offer prenatal screening if you are both found to be carriers of one of these conditions. 

Infectious diseases

This will check if you have HIV, Hepatitis B and Syphilis. Early detection and confirmation of these conditions enables your care pathway to be tailored to promote the best health outcome for you and your baby.

Dating Ultrasound Scan and Combined screening test

This scan is usually carried out between 11 – 14 weeks of your pregnancy. Your baby’s size will be measured and the measurements will be used to accurately date your pregnancy and give you an estimated date of delivery (EDD).

The scan will also check your baby’s general health and wellbeing and confirm if you are carrying one or more babies.

Screening for Down’s, Edwards’ and Patau’s syndrome.

During this scan you can consent to a screening test for Down's, Edwards' and Patau's syndrome.  These syndromes are genetic disorders that occur when there are extra copies of certain chromosomes. The screening involves measuring a pad of fluid called the Nuchal Translucency (NT) at the back of the baby’s neck, and taking a sample of your blood to check some placental hormone levels.

This test is not diagnostic but will tell you whether you have a high or low chance of your baby being affected.  If your result is a high chance (greater than 1 in 150) you will be contacted and the result fully explained; and you will be offered further diagnostic testing.

The test should ideally be performed from when the baby’s length is 45mm – 84mm on scan.  If the baby is larger than this, the NT cannot be measured. However, you can still have a blood test which measures the pregnancy hormone levels.

Anomaly Scan

An anomaly scan can be carried out from 18+0 – 22+6 weeks of pregnancy.  However it is usually carried between 20-21 weeks. This is a detailed scan of all your baby’s organs and looks for any signs of abnormalities.

The scan also checks for the position of your placenta. In about 10% of pregnancies, the placenta may be located in the lower part of the uterus at this stage of pregnancy but changes position as your uterus grows in size. If this is the case, a further scan will be arranged when you are 32-34 weeks pregnant to re-assess the position of your placenta.

It may also be possible to find out the gender of your baby at the anomaly scan, although a correct diagnosis cannot be guaranteed. Please let the Sonographer know at the beginning of the scan if this is something you would like to know.


It is important to remember that screening is an informed choice. You can choose to accept all, some or none of the screening tests offered to you.  The midwife will ensure that you have a complete understanding of screening to help you make a decision that is right for you and your family.