Ultrasound scans

It’s important to remember that scans are another kind of test to confirm the health of your baby. Ultrasound is a medical examination. Sonographers need to be able to concentrate and as such it is not recommended that young children attend. You will normally be offered two scans in pregnancy. The first is known as the dating scan at around 12 weeks of pregnancy and the second (sometimes called the anomaly scan) is performed at around 20 weeks gestation. This second scan will look in detail at your baby’s bones, heart, brain, spine, face, kidneys and stomach. It is important to remember that the scan cannot find everything that could be of concern about your baby. The quality of the images depends on several factors, including body mass index and fibroids. If you wish to know the sex of your baby, you can ask the sonographer, although it isn’t always possible to see clearly. All pregnant women in the UK are offered antenatal screening tests. A screening test in pregnancy cannot give you a yes/no answer as to whether your baby has a condition. It can only tell you what the chances are of your baby being affected. Screening tests in pregnancy include blood tests and ultrasound scans (ultrasound scans can suggest there might be a condition (as in screening for Down’s syndrome) or confirm there is a condition (as in diagnosing spina bifida)).

• Results are most often reported as a statistical chance and sometimes the terms “increased chance” or “low chance” will be used.
• The terms “risk” and “chance” refer to the possibility of an event happening. For example, a chance of 1 in 100 means that out of 100 women with this result, 1 will have a baby with a syndrome and 99 will not. This is the same as a 1% chance that the baby has a syndrome and a 99% chance that the baby does not.
• Most women will be reassured by the results but some (approximately 5%) will be given a result that leads to decisions about diagnostic testing. It is your choice to have any test.
• Diagnostic tests such as CVS and Amniocentesis carry a small risk (between 0.5 and 1%) of miscarriage which means the decision about whether to have them can be difficult. Unfortunately, there is no other way of knowing for sure whether your baby has Down’s syndrome and certain other genetic disorders.
• A diagnostic test in pregnancy can tell you for definite whether your baby has a condition or not. Diagnostic tests in pregnancy include CVS, amniocentesis and ultrasound scans.
• All tests should be fully explained to you by your doctor or midwife before you have them.

The results of your scan will be given to you on the day by the sonographer completing the scan. Most maternity units will provide you with scan pictures at a small cost.

Screening tests for chromosomal anomalies

A screening test can find out if you, or your baby, have a high or low chance of having a health problem. Inside the cells of our bodies there are tiny structures called chromosomes. These chromosomes carry the genes that determine how we develop. You will be offered a screening test to see how likely it is that your baby will have a abnormality in their chromosomes (Down’s, Edward’s or Patau’s syndrome). This test can be performed between 11 and 20 weeks and involves you having an ultrasound scan and a blood test. These tests are time critical, so it is very important that you attend for your scheduled appointment. If you are unable to attend contact the ultrasound department to rearrange as soon as possible. There are several different testing options available, so it is worth researching this early on. You will be contacted by the maternity unit if the results come back as high risk and you will be offered further testing. You do not have to have any testing if you don’t want to.

Blood tests

At the first booking appointment your midwife will recommend blood tests for Hepatitis B, HIV, syphilis, full blood count, blood group and electrophoresis (sickle cell and thalassemia screening). Some maternity units may also check your blood glucose levels. You may need a blood test for glucose tolerance later in pregnancy to screen for a condition called gestational diabetes. Your full blood count will be taken again later in pregnancy to ensure your iron levels remain normal. If your blood group is rhesus negative you may be offered some further tests, or you may be offered an injection of Anti-D during pregnancy. Around 15% of women are rhesus negative. Your midwife will explain this to you fully if needed. It’s useful to know your blood group in case you need to be given blood – for example, if you have heavy bleeding (haemorrhage) during pregnancy or after birth.

Anaemia

Anaemia makes you tired and less able to cope with loss of blood when you give birth. You should be offered screening for anaemia at your booking appointment and again at 28 weeks. If tests show you’re anaemic, you’ll probably be offered iron and folic acid.

Screening tests and ultrasound scans

During pregnancy you will be offered several screening tests to try and find any health problems that could affect you or your baby. It is your decision whether or not to have any of these tests. Read the “Screening tests for you and your baby” booklet from the link at the end of this page. It is important to look through the booklet before your first meeting with your midwife as it contains important information about your screening choices. The booklet is available in different languages.