Antenatal screening tests can detect maternal infections and pregnancy complications. Read for information on glucose tolerance tests, pre-eclampsia checks and more.
At your antenatal appointments you will be offered a number of prenatal screening tests to check your health, and to look for conditions that may affect your baby before and after birth. Antenatal screening test are done to help avoid health problems in you and your baby. For this reason, your health professionals will usually recommend you decide to have the tests. However, all tests are optional.
Blood pressure in pregnancy
Your midwife or doctor will take your blood pressure at every antenatal visit. Although blood pressure may naturally be higher in mid to late pregnancy, sometimes a rise in blood pressure in pregnancy (hypertension) can indicate a condition such as pre-eclampsia.
A urine test is simple and quick, and you will be asked to provide a sample at your antenatal visits.
Urine testing is used to check whether you have protein in your urine, which may indicate you have an infection in your bladder or kidneys. Certain maternal infections can trigger a premature birth.
Protein in your urine could also be a sign that you have pre-eclampsia.
Sugar in your urine could indicate gestational diabetes but you will need a second glucose tolerance test to be sure (see below). One of the problems with diabetes is that it can cause your baby to be larger than is healthy for you or the baby.
Glucose tolerance test
The glucose tolerance test is a test for both diabetes and gestational diabetes. Your blood will be taken after you have fasted for six hours. You will then be given a glucose drink and more blood is taken. The blood sugar level should rise and then quickly return to normal. This test is usually given to women if a urine test shows they might have diabetes, and as routine to some groups of mothers at greater risk of developing gestational diabetes.
Antenatal screening tests for infectious diseases
You will be offered a blood test to screen for the following:
- hepatitis B
- rubella immunity (german measles).
Although it is your choice to have these tests, your health professionals may recommend them - knowing about these infectious diseases in pregnancy can help to make sure that you and your baby stay as healthy as possible. A test will also confirm your blood group, and whether you are rhesus positive or rhesus negative.
NCT's helpline offers practical and emotional support in all areas of the antenatal stage, birth and early parenthood: 0300 330 0700. We also offer antenatal courses which are a great way to find out more about birth, labour and life with a new baby.
NHS Choices gives full information on the checks and tests offered when you are pregnant.