Quality statement 2: Antenatal assessment of pre-eclampsia risk

This quality statement updates and replaces quality statement 7: risk assessment – pre-eclampsia in NICE's quality standard on antenatal care.

Quality statement

Pregnant women at increased risk of pre-eclampsia at the booking appointment are offered a prescription of 75–150 mg of aspirin[3] to take daily from 12 weeks until birth.

Rationale

Aspirin prophylaxis, unless contraindicated, reduces the occurrence of pre-eclampsia, preterm birth and fetal and neonatal mortality in women at increased risk of developing the condition (if they have 1 high risk factor or more than 1 moderate risk factor for pre-eclampsia).

Quality measures

Structure

a) Evidence of local arrangements to ensure that pregnant women have their risk factors for pre-eclampsia identified and recorded at the booking appointment.

Data source: Local data collection.

b) Evidence of local arrangements to ensure that pregnant women at increased risk of pre-eclampsia at the booking appointment are offered a prescription of 75–150 mg of aspirin (unless contraindicated) to take daily from 12 weeks until birth.

Data source: Local data collection.

Process

a) Proportion of pregnant women who have their risk factors for pre-eclampsia identified and recorded at the booking appointment.

Numerator – the number of women in the denominator whose risk factors for pre-eclampsia are identified and recorded.

Denominator – the number of pregnant women attending a booking appointment.

Data source: The Maternity Services Data Set collects data on the following risk factors at booking: hypertension, renal disease, diabetes, autoimmune disease and obstetric diagnoses from previous pregnancies including 'severe pre-eclampsia requiring preterm birth', 'eclampsia' and 'gestational hypertension'.

b) Proportion of pregnant women at increased risk of pre-eclampsia at the booking appointment who are offered a prescription of 75–150 mg of aspirin (unless contraindicated) to take daily from 12 weeks until birth.

Numerator – the number of women in the denominator offered a prescription of 75–150 mg of aspirin to take daily from 12 weeks until birth.

Denominator – the number of pregnant women at increased risk of pre-eclampsia and without contraindications to aspirin at the booking appointment.

Data source: Local data collection.

Outcome

Incidence of pre-eclampsia in women at increased risk of developing pre-eclampsia.

Data source: The Maternity Services Data Set collects data on obstetric conditions diagnosed in the current pregnancy, including severe pre-eclampsia, severe pre-eclampsia requiring preterm birth and eclampsia.

What the quality statement means for different audiences

Service providers ensure that systems are in place to offer pregnant women at increased risk of pre-eclampsia at the booking appointment a prescription of 75–150 mg of aspirin (unless contraindicated) to take daily from 12 weeks until birth.

Healthcare practitioners offer pregnant women at increased risk of pre-eclampsia at the booking appointment a prescription of 75–150 mg of aspirin (unless contraindicated) to take daily from 12 weeks until birth.

Commissioners ensure they commission services that offer pregnant women at increased risk of pre-eclampsia at the booking appointment a prescription of 75–150 mg of aspirin (unless contraindicated) to take daily from 12 weeks until birth.

Pregnant women who have a higher risk of developing pre-eclampsia (a pregnancy-related rise in blood pressure with protein in the urine that happens in some pregnancies) are offered a prescription of aspirin (unless this is unsuitable) to take every day from 12 weeks of pregnancy until their baby is born.

Source guidance

Definitions of terms used in this quality statement

Booking appointment

The appointment where the woman enters the maternity care pathway.

[NICE's guideline on antenatal care for uncomplicated pregnancies, appendix D]

Increased risk of pre-eclampsia

Women are at an increased risk of pre-eclampsia if they have 1 high risk factor or more than 1 moderate risk factor for pre-eclampsia.

High risk factors include:

  • hypertensive disease in a previous pregnancy

  • chronic kidney disease

  • autoimmune disease, such as systemic lupus erythematosus or antiphospholipid syndrome

  • type 1 or type 2 diabetes

  • chronic hypertension.

Moderate risk factors include:

  • first pregnancy

  • age 40 years or older

  • pregnancy interval of more than 10 years

  • body mass index (BMI) of 35 kg/m2 or more at first visit

  • family history of pre-eclampsia

  • multi-fetal pregnancy.

[NICE's full guideline on hypertension in pregnancy]

Pre-eclampsia

New hypertension (over 140 mmHg systolic or over 90 mmHg diastolic) presenting after 20 weeks of pregnancy and the coexistence of 1 or more of the following new-onset conditions:

  • proteinuria (urine protein:creatinine ratio 30 mg/mmol or more, or albumin:creatinine ratio of 8 mg/mmol or more, or at least 1 g/litre [2+] on dipstick testing) or

  • other maternal organ dysfunction:

    • renal insufficiency (creatinine 90 micromol/litre or more, 1.02 mg/100ml or more)

    • liver involvement (elevated transaminases [alanine aminotransferase or aspartate aminotransferase over 40 IU/litre] with or without right upper quadrant or epigastric abdominal pain)

    • neurological complications such as eclampsia, altered mental status, blindness, stroke, clonus, severe headaches or persistent visual scotomata

    • haematological complications such as thrombocytopenia (platelet count below 150,000/microlitre), disseminated intravascular coagulation or haemolysis

  • uteroplacental dysfunction such as fetal growth restriction, abnormal umbilical artery Doppler waveform analysis, or stillbirth.

[NICE's guideline on hypertension in pregnancy, terms used in this guideline]



[3] Although this use is common in UK clinical practice, at the time of publication (July 2019), aspirin did not have a UK marketing authorisation for this indication. Community pharmacies cannot legally sell aspirin as a pharmacy medicine for prevention of pre-eclampsia in pregnancy in England. Aspirin for this indication must be prescribed. The prescriber should see the summary of product characteristics for the manufacturer's advice on use in pregnancy. The prescriber should follow relevant professional guidance, taking full responsibility for the decision. Informed consent should be obtained and documented. See the General Medical Council's Prescribing guidance: prescribing unlicensed medicines for further information.