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- Why am I being offered aspirin?
- What is pre-eclampsia?
- Am I at risk for developing pre-eclampsia?
- What is fetal growth restriction?
- Am I at risk of developing fetal growth restriction?
- Will I need any other tests for pre-eclampsia or fetal growth restriction?
- What national guidance does this leaflet refer to?
- Who do I get in touch with for more information?
Why am I being offered aspirin?
During pregnancy and the postnatal (after birth) period, some women and birthing people have an increased chance of developing pre-eclampsia or fetal growth restriction (see explanation of these conditions below).
Midwives assess all pregnant women and birthing people at booking regarding their chances of developing pre-eclampsia, or fetal growth restriction. Often, these conditions co-exist and risk factors overlap.
Those with risk factors who may be more likely to develop these conditions will be advised to take 150mg of aspirin in the evening by mouth after food, if possible, from 12-16 weeks of pregnancy until 36-weeks of pregnancy.
There are studies that show that this can help lower the chances of developing pre-eclampsia and fetal growth restriction.
Aspirin belongs to a group of medicines called antiplatelet drugs. These medicines stop the platelets in your blood sticking together so you are less likely to get blood clots.
Your midwife or obstetrician will advise you how you can obtain aspirin 150mg.
What is pre-eclampsia?
Pre-eclampsia is a complication that occurs in 5 to 8 in every 100 pregnancies.
It involves a rise in blood pressure which is accompanied by a leakage of protein from the kidneys into your urine. This protein can be found by testing your urine at each visit before giving birth.
In severe cases it can cause:
- headaches
- visual disturbances
- stomach pain
- facial swelling
- nausea
These symptoms can slow the growth of your baby leading to fetal growth restriction, see below.
Am I at risk for developing pre-eclampsia?
Pre-eclampsia can occur in any pregnancy, but you are at higher risk if:
- your blood pressure was already high before you became pregnant
- your blood pressure was high in a previous pregnancy
- you have a medical disorder such as diabetes or a kidney condition
- you have a condition that affects the immune system such as lupus
The importance of other risk factors is less known but generally are more likely to develop pre-eclampsia if you have 2 of the following:
- aged 40 or over
- this is your first pregnancy
- it is more than 10 years since your last pregnancy
- your BMI is 35 or more when you first see your midwife
- you have a family history of pre eclampsia
- if you are expecting twins or triplets.
What is fetal growth restriction?
Babies who are small for gestational age (SGA) may be naturally small and healthy or may be smaller because they are growth restricted (FGR feta growth restriction).
In general smaller babies may not have the energy reserves to cope with additional stress, such as labour, and also have a slightly higher chance of stillbirth later in pregnancy.
Am I at risk of developing fetal growth restriction?
Fetal growth restriction is more likely if you have had a previously small or growth restricted baby, or any of the below risk factors:
- you were smoking in pregnancy or taking recreational drugs
- are aged over 40 years
- have a medical disorder such as diabetes, a kidney condition, or if you have a condition that affects the immune system such as lupus
- previously had a pregnancy affected by high blood pressure or pre-eclampsia
- have had a previous preterm birth or second trimester miscarriage in which problems with your placenta were involved
- had a previous stillbirth with a normal weight baby for the gestation
- have a low PAPP-A level (blood test checked during the early combined screening test). The screening team will contact you about this if it is found to be low.
- have had gastric bypass surgery in the past
- have significant recurrent bleeds in this pregnancy
- have a single umbilical artery in your placent
- have adult congenital heart disease (ACHD) as for example Post Fontan.
Will I need any other tests for pre-eclampsia or fetal growth restriction?
If you have any of these risk factors, you will be referred to the obstetric antenatal clinic for planning the pregnancy.
You may be offered an extra scan performed at the time of the anomaly (20-weeks) scan to check the uterine artery Dopplers (UADs). This assesses the flow of blood in the vessels which supply the uterus (womb) and can provide an indication as to whether the baby will grow to its full potential or raise the possibility of developing pre-eclampsia.
Very rarely the sonographer may not be able to obtain your UAD’s due to technically difficulties. According to the results, your consultant will discuss the on-going care plan for you including extra growth scans in the third trimester. You will also be offered regular scans two to four weekly after 28 weeks or 32 weeks depending on your risk. Your obstetrician and midwife will discuss this with you.
What national guidance does this leaflet refer to?
This leaflet has been created in response to the following national guidance:
NHS England » Saving babies’ lives version three: a care bundle for reducing perinatal mortality
Overview | Hypertension in pregnancy: diagnosis and management | Guidance | NICE
Who do I get in touch with for more information?
For more information, speak with your midwife or call Maternity Triage on 01903 285269.
The information here is for guidance purposes only and is in no way intended to replace professional clinical advice by a qualified practitioner.