Ultrasound scans
Maternity Scans:
One adult is allowed to accompany you in the scan room.
As part of your antenatal care, you will be offered various tests to check on the health of your developing baby and for conditions that may affect you or your baby. It is important you book for antenatal care as early as possible in your pregnancy. This will help you get these tests at the appropriate time, and benefit from other care for you and your baby.
When are Scans Offered?
There are 2 routine ultrasound scans offered in England:
- Nuchal Dating Scan - 11+2 -14+1 scans
- Anomaly Scan – 18-20+6 weeks
Screening tests are used to find people at higher chance of having a health problem. This means they can get earlier, potentially more effective treatment, or make informed decisions about their health. It can be helpful to imagine screening like putting people through a sieve. Most people pass straight through but a small number get caught in the sieve. The people caught in the sieve are those considered to have a higher chance of having the health problem being screened for.
Screening tests are not perfect. Some people will be told that they or their baby have a high chance of having a health problem when in fact they do not have the problem. Also, a few people will be told that they or their baby have a low chance of having a health problem when in fact they do have the problem.
First Trimester
During the first appointment with the midwife, you will be offered several tests. The tests are to check for different conditions that may affect you or your baby. The results of these tests are given at a future appointment; however, you may well be contacted earlier if a result requires some action. These tests include hepatitis and HIV.
You can choose to have a screening test for chromosomal abnormalities when you attend for your screening and ultrasound scan visit (between 11+2 and 14+1 weeks of pregnancy).
The blood test measures the amount of two proteins PAPPA and FREE BETA HCG. These proteins appear naturally in your blood during pregnancy. A change in the level of these proteins can indicate an increased chance of abnormality, but doesn't give you a certain diagnosis.
The ultrasound uses sound waves to make a picture of your baby on a screen. It can show the age and position of your baby, and also if there is more than one baby. During the scan, the ultra-sonographer will also measure the amount of fluid behind the neck of the baby - this test is called the nuchal translucency. This measurement, along with the baby’s age, your age, and the results of the biochemical tests will allow us to calculate the individual risk of the baby having a chromosomal abnormality such as Down’s syndrome. If the risk is increased, you will be offered the opportunity to discuss further with the doctor or midwife.
If it is considered appropriate for further follow up tests, the appropriate diagnostic tests will either be chorionic villus sampling (CVS) where a small amount of afterbirth is tested under ultrasound, or amniocentesis where a small amount of fluid from around the baby is tested.
Sickle cell and thalassaemia (SCD): screening in pregnancy for SCD and thalassaemia involves having a blood test. It is best to have the test ideally by eight weeks, to allow for your results to appear on your electronic medical records by 10 weeks. This test is offered to all women cared for through our Trust.
The screening will find out if you are a carrier of the sickle cell or thalassaemia gene and therefore likely to pass it on to the baby.
Second Trimester Screening
If you book after 13 weeks and 6 days, you can still have a blood test. This test is called the Quad test and includes four markers: Free-beta HCG, AFP, Unconjugated Estriol and Inhibin-A. It will detect around 80% of Down’s syndrome cases.
Read more about Quad Tests - Screening tests for you and your baby.