
Screening Tests in Pregnancy
A number of screening tests are offered to you during pregnancy in line with national recommendations:
- Infectious diseases (HIV, Hepatitis B & Syphilis)
- Sickle Cell and Thalassaemia
- Down’s, Edwards’ & Patau’s syndromes
- Anomaly scan
For more information on your screening choices visit www.nbt.nhs.uk
For tests that are available during pregnancy and after your baby has been born, please watch this NHS video. (Subtitles available in English, as well as Arabic, Bengali, Chinese, French, Latvian, Lithuanian, Polish, Portuguese, Punjabi, Romanian, Somali and Urdu. A British Sign Language version is also available.)
You will be provided with information relating to these screening tests and will have the opportunity to discuss your screening choices with the midwife during your antenatal booking appointment. You can choose to accept or decline screening in pregnancy.
For information explaining these screening tests:
Download the ‘Screening test for and your baby’ booklet at www.gov.uk
Download the 'Screening test for you and your baby' easy read booklet at www.gov.uk
To save this 'Screening Test for you and your baby' booklet on your smart phone home screen: please go to www.gov.uk
Infectious Diseases Screening
These tests are recommended as early treatment and care can protect your health and reduce the chance of passing the infection onto your baby, partner or other family members. Screening is best undertaken in early pregnancy, but can be done at any time. If you decide not to have the test, a specialist midwife will contact you to discuss a second offer.
Sickle Cell &Thalassaemia
This test is to find out if you are a carrier of the sickle cell or thalassaemia gene and therefore likely to pass it on to your baby.
- Alpha Zero Thalassaemia: description in brief
- Beta thalassaemia carrier: description in brief
- Delta beta thalassaemia carrier: description in brief
- Haemoglobin C carrier: description in brief
- Haemoglobin D carrier: description in brief
- Haemoglobin E carrier: description in brief
- Haemoglobin lepore carrier: description in brief
- Haemoglobin O Arab carrier: description in brief
- Sickle cell and thalassaemia screening: information for fathers
- Baby at risk of having sickle cell disease: description in brief
- Baby at risk of having thalassaemia: description in brief
- Sickle cell disease: managing the condition
First Trimester Combined Screening (FTCS)
This combined screening test is offered to assess the chance of your baby being born with:
-
Down’s syndrome (Trisomy 21)
-
Edwards’ syndrome (Trisomy 18)
-
Patau’s syndrome (Trisomy 13)
This screening test can only be undertaken from 11 weeks and two days (11+2) and 14 weeks and one (14+1) day of gestation.
You can choose to:
-
not have screening
-
have screening for Down’s, Edwards’ and Patau’s syndrome.
-
have screening for Down’s syndrome only.
-
have screening for Edwards’ and Patau’s syndrome only.
This screening test includes a blood test and an ultrasound scan. At the scan your pregnancy will be dated and the fluid on the back of your baby’s neck is measured.
FTCS Detection Rate
Screening strategy Threshold |
Standardised DR |
Acceptable standardised SPR |
Achievable standardised SPR |
T21 |
85% |
1.8 to 2.5% |
1.9 to 2.4% |
T18/T13 |
80% |
0.1 to 0.2% |
0.13 to 0.17% |
T21/T18/T13 |
1.8 to 2.5% |
1.9 to 2.4% |
|
Quadruple (T21) |
80% |
2.5 to 3.5% |
2.7 to 3.3% |
Occasionally, the FTCS test may not be able to be performed. If this is the case the healthcare professional undertaking your scan will inform you of the reason(s) for this and you will be offered a Quadruple test in the second trimester for Down’s Syndrome screening with your community midwife.
The Quadruple test does not screen for Edwards’ and Patau’s syndrome. Screening for Edwards’ and Patau’s Syndrome in the second trimester is at the 18-20+6 week anomaly scan.
FTCS Results
If you choose to have this screening test the result is given in figures, for example: a chance of; one in 50, one in 500, one in 50,000 and so forth.
If your result is one in 151 or greater in number (low chance result) you will receive the result in the post within 14 calendar days of the screening test.
If your result is between one in two and one in 150 (high chance result) a specialist midwife will contact you to discuss the result, options and further testing available.
Quadruple Test Results
If you have this screening test the result is given in figures, for example: a chance of; one in 50, one in 500, one in 50,000 and so forth.
If your result is one in 151 or greater in number (low chance result) you will receive the result in the post within 14 calendar days of the screening test.
If your result is between one in two and one in 150 (high chance result) a specialist midwife will contact you to discuss the result, options and further testing available.
Ultrasound Scans
Dating Scan – this scan is undertaken ideally between 10 to 14 weeks of pregnancy to accurately date your pregnancy. A dating scan is offered if you choose not to have Down’s, Edwards’ and Patau’s syndrome screening (FTCS).
Anomaly Scan – the scan usually takes place between 18 and 20+6 weeks of pregnancy to check your baby’s development. In most cases the scan will show that your baby appears to be developing as expected but sometimes a problem may be found/suspected and referral to Fetal Medicine will be made.
For more information:
- Antenatal Results & Choices (ARC) visit www.arc-uk.org
- Conditions screened for as part of the anomaly scan www.gov.uk
- Resources for prospective parents about Downs syndrome www.downs-syndrome.org.uk
- Resources for prospective parents about Edwards & Patau's syndrome www.soft.org.uk
Anaemia
Anaemia is most commonly caused by a low haemoglobin level (Hb) in the red blood cells. The Hb is usually tested as part of the ‘full blood count’. Hb carries oxygen and nutrients around the body and to your baby. Anaemia can make you feel very tired and may make you less able to cope with losing blood at the time of the birth. If you are anaemic you will be offered advice on diet and possibly iron supplements.
For more information visit A Healthy Pregnancy
Blood group & antibodies
This test tells us whether you belong to Group A, B, O or AB whether your blood is Rhesus Positive (Rh +ve) or Negative (Rh -ve) and whether you have any antibodies (foreign blood proteins).
Hepatitis B
Hepatitis B is a virus which affects the liver. Specialist care will be provided for pregnant women with Hepatitis B. You will be advised for your baby to have a course of vaccinations in the first year of their life to reduce the risk of baby being affected by this condition. Infection can be prevented in 90% of cases if the first dose of vaccine is given at birth and the full course of vaccines completed on time.
Hepatitis B: what does my positive screening result mean? Visit www.gov.uk
For information on Protecting your baby against Hepatitis B, visit www.gov.uk
Syphilis
Syphilis is a sexually transmitted disease which can cause serious problems for your baby, if left untreated. If detected, treatment can be offered with antibiotics. Specialist care will be provided for women with this condition.
Syphilis: what does my positive screening result mean? Visit www.gov.uk
For more information visit www.nhs.uk
HIV
The Human Immunodeficiency Virus (HIV) affects the body’s ability to fight infection. This test is important because any woman can be at risk. It can be passed on to your baby during pregnancy, at birth or through breastfeeding. Specialist care/ treatment in pregnancy can greatly reduce the risk of this infection being passed from mother to child.
HIV: what does my positive screening result mean? Visit www.gov.uk
Additional Blood Tests
Additional blood tests may be offered as necessary, for example to check for infections that could cause harm to your developing baby, but rarely cause problems for the mother.
Immunise against Flu, Whooping cough & German measles
For more information on immunation against against Flu (Influenza), Whooping cough (Pertussis) and German measles (Rubella) download www.gov.uk
For more information on MMR visit www.gov.uk
For more information on how to protect your child from Measles visit www.gov.uk
For more information on how to protect yourself and others from Measles visit www.gov.uk
More information on tests
For more information visit:
You can get great information about screening on www.nhs.uk
Accessible on your phone, there’s a general screening page which links to all the different screening programmes.
www.nhs.uk contains the same information as the screening leaflets but in a more screen-friendly format as the website adapts to whatever screen size is used. It also provides additional information for people looking for more detail.
It also includes videos. For example, the screening tests in pregnancy page has the new antenatal and newborn screening animation.