During your pregnancy, you'll be offered a range of tests, including blood tests and ultrasound baby scans.
They are designed to help make your pregnancy safer, check and assess the development and wellbeing of you and your baby, and screen for particular conditions. You don't have to have any of the tests, but you need to understand the purpose of them so you can decide whether to have them or not. Discuss this with your maternity team.
Public Health England have published a short animation explaining antenatal and new-born screening. You can see it here.
You will be asked to be weighed at your booking appointment. Your height and weight are used to calculate your BMI (body mass index). Women who are overweight for their height are at increased risk of problems such a gestational diabetes or high blood pressure during pregnancy.
Most women put on 10-12.5kg (22-28lb) in pregnancy, most of it after they are 20 weeks pregnant. Much of the extra weight is due to the baby growing, but your body also stores fat for making breast milk after the birth. During your pregnancy, it's important to eat the right foods and exercise regularly.
You'll be asked to give a urine sample at your antenatal appointments. Your urine is checked for several things, including protein (albumin). If this is found in your urine, it may mean you have an infection that needs to be treated. It may also be a sign of pre-eclampsia.
Pre-eclampsia affects 5% of pregnancies and can lead to a variety of problems, including seizures (fits). If left untreated it can be life threatening. Pre-eclampsia can also affect the growth and health of the baby. Women with the condition usually feel perfectly well, so it is important you have this test.
Your blood pressure will be taken at every antenatal visit. A rise in blood pressure later in pregnancy could be a sign of pregnancy-induced hypertension or pre-ecplampsia.
It's very common for your blood pressure to be lower in the middle of your pregnancy than at other times. This isn't a problem, but it may make you feel lightheaded if you get up quickly. Talk to your midwife if you're concerned about it.
As part of your antenatal care you'll be offered several blood tests. Some are offered to all women, and some are only offered if you might be at risk of a particular infection or inherited condition. All the tests are done to make your pregnancy safer or to check that your baby is healthy, but you don't have to have them if you don't want to. Talk to your midwife or doctor and give yourself enough time to make your decision. Routine blood tests will be offered and taken at your booking appointment (they should be taken prior to 11 weeks of pregnancy)and again at 28 weeks of pregnancy.
If you choose to have the Maternal serum screening that gives you a risk of your baby having Down’s, Edwards or Patau’s syndrome then this should be taken by the time you are 14 weeks (most women will have the blood test taken following their early dating scan alongside the nuchal fold measurement). If it is not possible to measure the nucal fold then the Quad test can be taken from 14 to 20 weeks of pregnancy. If you chose to have this test you will receive a letter confirming your result through the post.
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 birth.
The test tells you whether you are blood group rhesus negative or rhesus positive. Women who are rhesus negative may need extra care to reduce the risk of rhesus disease.
People who are rhesus positive have a substance known as D antigen on the surface of their red blood cells. Rhesus negative people do not. A rhesus negative woman can carry a baby who is rhesus positive if the baby's father is rhesus positive. If a small amount of the baby's blood enters the mother's bloodstream during pregnancy or birth, the mother can produce antibodies against the rhesus positive cells (known as anti-D antibodies).
This usually doesn't affect the current pregnancy, but if the woman has another pregnancy with a rhesus positive baby, her immune response will be greater and she may produce a lot more antibodies. These antibodies can cross the placenta and destroy the baby's blood cells, leading to a condition called rhesus disease, or haemolytic disease of the newborn. This can lead to anaemia and jaundice in the baby.
Anti-D injections can prevent rhesus negative women from producing antibodies against the baby. Rhesus negative mothers who haven't developed antibodies are therefore offered anti-D injections at 28 weeks of pregnancy, as well as after the birth of their baby. This is safe for both the mother and the baby.
Anaemia makes you feel tired and less able to cope with loss of blood when you give birth. If tests show that you're anaemic, you'll probably be given iron and folic acid.
For a low-risk pregnancy you will be booked in for two routine ultrasounds scans. The first will take place between 11-13 weeks of pregnancy and is more commonly known as the 'dating' scan as it enables the sonographer to provide you with an estimated due date for your baby's birth.
The second scan is taken between 18-20 weeks and is also known as the 'anomaly' scan. This scan measures your baby's growth and checks for structural abnormalities.
We are offering Carbon Monoxide monitoring to all women throughout pregnancy whenever you’ve seen in community and when you’re seen in our hospitals. We’re particularly concerned about taking these at booking and at 36 weeks.
The glucose tolerance test is performed to screen women at risk of gestational diabetes
Glucose tolerance tests are not currently carried out at Peterborough City Hospital due to Covid-19 restrictions but you will have HbA1c (what’s this?) and fasting blood glucose tests done.
At Hinchingbrooke the glucose tolerance test (GTT) are done in phlebotomy but can occasionally be done in our Maternity Day Assessment Unit (MDAU) and can be planned for when you're 27 weeks.
We ask that you fast overnight but do allow sips of water, when the day of your appointment arrives you will receive a blood test on arrival which is followed by a sugary drink. You will then sit and wait for 2 hours until we require your second blood sample, after this has taken place you can eat and drink as normal.
A letter will be sent to you with your test results, however if your tests show any abnormality you will receive a call from a midwife on MDAU.
Screening Criteria:
The purpose of this screening is to find out how likely it is that your baby has these conditions.
Your community midwife at your first appointment will discuss the screening offer with you and discuss your options.
Screening is not compulsory and you could either decide to have the screening for all the three conditions, only for Down’s syndrome Screening, only for Edward’s and Patau’s or decline the screening altogether.
To find out more information about these conditions you can read information available at https://www.gov.uk/government/publications/screening-tests-for-you-and-your-baby-description-in-brief in English, 12 other languages, easy to read versions and audio versions. If you are finding hard to decide whether to have the screening you can contact the Screening Team on 01223 348666 or consult Antenatal Results and Choices website (ARC).
Screening tests for you and your baby
A leaflet explaining the screening tests offered during and after pregnancy.
This leaflet is available in English and 12 other languages. Mp3 audio files are also available for people with sight loss.
Easy read versions of the booklet for people with learning disabilities are also available to download.