From Bench to Bedside: Maternity Early Warning Scores Research and the Journey to National Adoption in the UK

Dr Lucy Mackillop

Oxford University Hospitals NHS Foundation Trust

Maternity Early Warning Scores

Maternity Early Warning Scores (MEWS) are widely used throughout hospitals in the UK to highlight when additional care is needed to protect the health of the expectant mother and baby. Their implementation varies widely across the country, and the majority of MEWS have been developed by clinical consensus.

The Pregnancy Physiology Pattern Prediction (4P) Study

This prospective UK cohort study collected vital sign data (blood pressure, heart rate, respiratory rate, temperature and oxygen saturations) from 1041 women monthly during their pregnancies, intrapartum and and daily for 2 weeks postpartum.

Gestation specific reference ranges were constructed for each vital sign comprising smoothed centiles (3rd, 10th, 50th, 90th and 97th with corresponding 95% confidence intervals).

Clinical Validation

The clinical response to higher scores was developed by 30 midwives, doctors and other experts using a Delphi exercise which allowed experts to reconsider their opinions based on the anonymised opinions of others. This ensures that the new national MEWS not only identifies potential problems, but also provides clear guidance on the appropriate escalation of care.

National rollout

The new approach is being rolled out across the NHS in England with the aim that every organisation will have implemented MEWS across England by March 2026. Latest adoption figures will be presented.

References: