A Dad’s Guide to Antenatal Tests and Checks
During pregnancy there are many tests offered which aim to detect any health problems that could affect your partner or your baby. These tests include everything from urine tests to blood tests and ultrasound scans to blood pressure monitoring!
These tests are all available free of charge under NHS care and are designed to help ensure that your partner and unborn baby are well, as well as to check for any potential health issues.
Having these tests and checks is a choice, they are not compulsory. However, it is important to understand the purpose of all tests so that you can make an informed decision about consenting to, or declining them.
So here is the lowdown on what tests and checks are on offer during pregnancy:
Weight and height
This check is offered at the booking appointment at around week 9 of the pregnancy. Height and weight are used to calculate your partner’s BMI (body mass index) as there are some increased risks to women who are classed as ‘overweight’ such as gestational diabetes and pre-eclampsia.
Antenatal urine tests
At each antenatal appointment, the midwife can check your partner’s urine. She will be given a specimen bottle to collect a sample to bring to each appointment.
The urine specimens are checked for several things, including the presence of protein. Sometimes a trace can be found and this is not a cause for concern, but it can be an indicator of an infection or even pre-eclampsia, a condition which can be very serious if not treated.
Blood pressure monitoring
Your partner’s blood pressure can be checked at every antenatal appointment. A rise in blood pressure in pregnancy, especially alongside the presence of protein in the urine and some other symptoms, can be a sign of pre-eclampsia.
A number of blood tests are offered during pregnancy. Not every woman is offered all tests, as some will be deemed higher risk of some conditions than others.
The blood tests your partner may be offered include:
- Blood group
Having a record of your partner’s blood group can be useful, in case she requires a blood transfusion for any reason, for example if she were to experience heavy bleeding during pregnancy or birth.
- Rhesus disease
When and if your partner’s blood group is checked, it can also be determined whether her blood is RhD negative or positive to help determine the possibility of Rhesus disease developing. Rhesus disease is only a risk if your partner has rhesus negative blood (RhD negative) and your unborn baby has rhesus positive blood (RhD positive).
Rhesus disease is a condition where antibodies in a pregnant woman's blood destroy her baby's blood cells. This wouldn’t cause your partner physical harm, but it can cause your baby to become anaemic and develop jaundice, a condition known as haemolytic disease of the foetus and newborn (HDFN).
If your partner is RhD negative, she will be offered injections of anti-D immunoglobulin to remove the RhD foetal blood cells from her blood before her body produces the antibodies to fight them.
In pregnancy, anaemia can leave a woman feeling very fatigued, and also put her at increased risk of complications in the event of blood loss during birth.
Women need much more iron when they are pregnant, as this is what the body uses to make haemoglobin, which is the part of red blood cells that carry oxygen. Women’s blood volume increases by up to 50% during pregnancy, and so a lot more iron is needed to make all that extra haemoglobin! In addition to this, women also need extra iron for their growing baby and placenta.
When a woman does not have enough iron to make the haemoglobin required, she becomes anaemic. Blood tests can spot whether this is likely to occur or has already so that action or treatment can be taken.
Problems in pregnancy: what can happen?
Women are classed to be at a higher risk of developing gestational diabetes (diabetes which usually develops after 28 weeks of pregnancy and disappears after birth) if they are overweight or have had gestational diabetes before.
If your partner is considered to be high risk for gestational diabetes, she may be offered blood tests to check for it as gestational diabetes can increase the risk of birth complications for both your partner and baby.
Problems in pregnancy: what can happen?
Blood tests for infections
Blood tests are also offered to all pregnant women to detect:
- Immunity to rubella – as contracting rubella in early pregnancy can cause serious harm to your unborn baby.
- Syphilis – it is important to know if this sexually transmitted infection is present as it can lead to miscarriage and stillbirth if left untreated.
- Hepatitis B – this virus can cause serious liver disease, and can also infect your baby.
- HIV – this is the virus that causes AIDS. HIV infection can be passed to a baby during pregnancy, during birth or by breastfeeding so being aware of the presence of the infection will significantly reduce the chance of the baby becoming infected.
If your partner is tested positive for any of these infections, they will be offered appropriate care and treatment to reduce the risks to themselves and your baby.
Nuchal Translucency Scan
You will be offered a nuchal translucency (NT) scan (usually carried out during your Dating Scan), to assess how likely the risk is that your baby has Down's syndrome.
The pocket of fluid under the skin at the back of your baby's neck can be measured using ultrasound. All babies have some fluid at the back of their neck, but often babies with Down's syndrome have more.
A screening test like NT can only estimate how high or low the risk of your baby having Down's syndrome is – not whether they definitely do or don’t. The NT scan identifies about 77% of babies who do have Down's syndrome.
Screening tests, however, are not infallible. Sometimes, a screening test can suggest that a baby has a high risk of having Down's syndrome, even though the risk is actually low. 5% (or one in 20 women) is wrongly given a high risk result following their NT scan.
In addition, it is not always possible to obtain the NT measurement, and depends on the position of the baby. If this is the case, you will be offered a different screening option.
Scans: What to expect
Combined Test (NT scan and blood test)
A screening test for Down's, Edwards' and Patau's syndrome is available between 10 and 14 weeks of pregnancy. It is called the combined test because it combines the NT scan with a blood test.
If you choose to have the combined test, a blood sample will be taken from you. At the dating scan, the NT scan will also be done, measuring the fluid at the back of the baby's neck. The information from these two tests in combination is used to work out the risk of the baby having Down's, Edwards' or Patau's syndromes.
Again, the combined test is not always infallible. The combined test picks up about 90% of babies with Down's syndrome (so more accurate than the NT scan on its own), but still 5% (or one in 20 women) is wrongly given a high risk result following the combined test.
In addition, the same potential issue exists as with the NT scan in isolation. It is not always possible to obtain the NT measurement, and depends on the position of the baby. If this is the case, you will be offered an alternative screening test.
The anomaly scan checks for structural abnormalities (anomalies) in the baby. The scan looks in detail at the baby's bones, heart, brain, spinal cord, face, kidneys and abdomen. It allows the sonographer to look specifically for 11 conditions, some of which are very rare.
The sonographer will also be look at what is around baby - the amount of amniotic fluid, the cord flow and where the placenta is positioned.
An amniocentesis can be carried out from week 15 of pregnancy. This is a diagnostic test, not a generic screening test, and as such is usually only offered when there is a significant risk that your baby will develop a serious condition or abnormality
In an amniocentesis, a very fine needle is put through the mother's abdomen into the uterus to collect a sample of the fluid around the baby. Cells from the baby are contained in the fluid, which can be tested.
An amniocentesis does have a risk of miscarriage, estimated at about 1 in 100.
There is also a risk of developing a bacterial infection. This is rare at less than 1 in 1,000, but still something to be aware of when making a decision about such a test.
Chorionic villus sampling (CVS)
CVS can be carried out between 11 and 14 weeks of pregnancy. This is a diagnostic test, not a generic screening test, and as such is usually only offered to women when there's a significant risk their baby will develop a serious condition or abnormality.
A very fine needle is used, usually put through the mother's abdomen into the placenta, to take a tiny sample of tissue. The cells from the tissue can then be tested.
One of the main risks associated with CVS is miscarriage, which is estimated to occur in 1-2% of women tested.
Should we have the tests done or not?
Each test will have its own perceived risks and benefits for you and your partner to weight up.
Many families decide to choose to have the tests offered so that they have as many options as possible and can be prepared if all is not well. This is absolutely fine and it is why the screening tests exist and are offered to all.
However, some parents may not wish to have some or any of the tests, and this is your choice too.
Screening tests are very safe, but can sometimes lead to uncertainty and difficult decisions. They cannot usually say if your partner or baby have a health problem for definite, just if your partner or baby are at a ‘high’ or ‘low’ risk of having the problem. This might lead to additional tests being offered - diagnostic tests like amniocentesis, which do carry more serious risks, including miscarriage. If you do not want to take the risks of a diagnostic test to get a definitive answer, then it is helpful to consider first whether you wish to consent to a screening test which might raise the question.
The results of diagnostic tests could, in some instances, potentially lead to decisions about whether to continue or end a pregnancy. Having further tests or termination will always be your decision, and health professionals will support you whatever you decide – although it is likely to be a distressing time whatever path you take. If you wish to avoid having to make a decision like this, then it is worth bearing this in mind when choosing which tests you wish to consent to.
These are all very personal decisions to make, and it is worth really discussing together with your partner what you both want to know and when, and, if there is anything which you do not want to know or be tested for. You can always choose to have some tests and not others, such as having the Dating Scan but declining the NT scan. Do your research and decide what is right for you both.
Tests and checks do not stop with the birth of your baby, there are also a range which are offered to your newborn from the moments after they are born which you will need to make a decision about.