All women will be offered a dating scan, and an 18- 20 week fetal anomaly ultrasound scan, in line with NICE and UK National Screening Committee recommendations.
Women also have routine blood tests (or ‘blood screening’) to find out the mother’s blood group and several other things. (For more detailed information about women’s experiences of antenatal screening see our ‘Antenatal Screening’ website). For more information on screening tests please see ‘Resources‘.
Though all the pregnancies considered here began in the usual way with early scans and blood test screening, they all differed subsequently because the baby was found to have problems. (See also ‘Having the 18-20 week scan and further tests’.)
Explains what she understood different scans were for.
The dating scan
Many people couldn’t remember much about early scans, particularly if they had experienced other scans later on in pregnancy. People we interviewed expressed a range of views about the purpose of the 12-week scan. Some thought it was to verify the pregnancy, work out likely dates for the baby’s birth and give parents a chance to see the baby. Others thought the scan was done to check that the baby was alive and that s/he had all the major organs and limbs. This scan is part of the screening test for Down’s syndrome known as the combined screening test it is most effective if done before 14 weeks (it is normally done as part of the dating scan 11- 14 weeks of pregnancy), women need to know about this option early enough and not delay the dating scan past 14 weeks if they want one (for more details see the section below on nuchal translucency scan).
Some people experiencing their first pregnancy didn’t realise when they were asked to ‘come back in a few days’ or told that someone else needed to look at the scan, that their baby had a problem. One man had been confused by what he was told at the first scan which seemed to cast doubt on the pregnancy.
He felt happy at seeing his baby for the first time on the screen and took scan pictures to…
Some people who had been told that the baby looked ‘structurally sound’ at the first scan, said they felt relieved that the pregnancy had moved onto ‘safe ground’, and decided to break the news to family and friends.
Her baby looked structurally fine on the 12-week scan and she and her partner decided to tell everyone about the pregnancy (a blood test shortly afterwards detected signs of spina bifida).
Most people were amazed and overawed by the sight of their baby on a screen, and said they treasured the photographs and videos from the scan. For people who ended up having a surgical termination, scan photographs of the baby were often the only memento they had of the baby.
She and her partner paid to have extra photographs of the baby’s 12-week scan.
Her mother has all the scan photos of her grandchildren up on her bedroom wall and her other…
Several men said that seeing the baby on the scan helped them get to know the baby – one man said the scan gave him ‘something to focus on rather than just a big bulge’. Not everyone felt that they bonded with the baby during the scan – one woman said she couldn’t relate the fuzzy images she saw on the scanner to her baby.
Sometimes 12-week scans were not reassuring, particularly when sonographers discovered that the baby looked small and that the dates might be wrong. Some women felt instinctively that something was wrong with the pregnancy – some had experienced bleeding – and so did not always believe sonographers when they said that the baby was alright. (See also ‘Feelings about the pregnancy‘).
She felt anxious and uncomfortable during her first scans.
Nuchal translucency scan
All pregnant women in England are now offered tests for Down’s syndrome. The tests can provide information about the chance of a baby having Down’s syndrome. These tests use blood samples taken from the mother, measurements taken from ultrasound scans (nuchal translucency scan/dating scan) or both to work out this chance. The NHS Fetal Anomaly Screening Programme now recommends that women have the combined screening for Down’s syndrome (blood test and nuchal translucency scan) rather than just the blood test or the nuchal translucency scan. The vast majority of units in England, Scotland and soon Wales now offer combined screening for Down’s syndrome.
Nuchal ultrasound scans are performed at 10-13 weeks of pregnancy. They measure a small fluid collection within the skin at the back of the baby’s neck (nuchal translucency) to help identify the risk of Down’s syndrome and other chromosomal abnormalities. The results can be combined with a blood test result (combined screening) to give a more accurate calculation but these tests cannot give a definite diagnosis. If the risk is more than 1 in 150, further tests will be offered. The nuchal translucency scan can also indicate cardiac or other problems, if the measurement of the fluid is the same or greater than 3.5mm, the mother will be advised and further tests may be offered along with a referral to a fetal medicine specialist. She will be given this information even if she has chosen not to have Down’s syndrome screening.
The nuchal scan has only fairly recently been offered routinely on the NHS and several people we talked to had chosen to pay for the scan to be done privately because they wanted to know whether the baby was at risk of Down’s syndrome and because they didn’t want to go for an amnio or CVS unless absolutely necessary (see ‘Information’ section – Diagnostic tests ).
A woman who had private fertility treatment said that when health professionals detected signs of abnormality in the baby during a nuchal scan, she was told that she needed to have more detailed scans in her local NHS hospital. One woman was offered a nuchal scan on the NHS and took her sister and twin babies with her – a decision she looked back on as ‘na‚àö√òve’.
The nuchal fold test showed that both her twin babies could have Down’s syndrome.
Non Invasive Prenatal Test (NIPT) is another screening test that can be used to detect Down’s syndrome. It is a non-invasive test using a maternal blood sample to test free-cell fetal DNA. During pregnancy, fragments of DNA from the placenta called free-cell fetal DNA circulate in the mother’s blood steam. These DNA fragments (CFFDNA) can be genetically tested along with the mother’s blood to show if there is an increase in the number of abnormal chromosomes. This screening test is not currently offered by the NHS, however some NHS Trusts have piloted the test and a number of maternity units do offer testing privately. The sample has to be sent outside the UK for analysis so the results take about two weeks to come back. The cost of the test varies between clinics.
Large scale studies show that the test has a detection rate of over 99% (ARC July 2017) and also tests for some other common chromosomal anomalies; Edwards syndrome (trisomy 18), Patau syndrome (trisomy 13) and Turner syndrome. It can be performed from 10 weeks of pregnancy and unlike amniocentesis and CVS has no risk of miscarriage. However if the NIPT gives a positive result, an amniocentesis is required for confirmation. For more information see RAPID (Reliable Accurate Prenatal non-Invasive Diagnosis) website or ARC (Antenatal Results and Choices) website. None of the people we interviewed had had this test.
Women who already experienced difficulties getting pregnant or carrying pregnancies to term, said that they found that every scan made them feel nervous. We also talked to women who had gone through two or more terminations because of they were carriers of a recessive gene, and they and their partners also felt extremely anxious about early scans in subsequent pregnancies.
Having ended two pregnancies because the babies had neural tube defects she is pregnant again but…
She dreads scans because of her previous experiences.
If the scan reveals either a suspected or confirmed abnormality, the woman should be informed by the sonographer at the time of the scan. It is essential that all practitioners performing fetal anomaly ultrasound screening should be trained to communicate abnormal findings to women, as such information is likely to have significant emotional impact.
Usually, sonographers will ask a senior sonographer colleague to confirm findings and this should be done immediately. If an abnormality is confirmed or suspected, referral is usually required, although some obvious major fetal abnormalities, such as anencephaly, may not require a second opinion (this should be decided by local guidelines).