Condition category
Pregnancy and Childbirth
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status

Plain English Summary

Background and study aims
The two most recent Confidential Enquiries into Maternal Deaths reports in the UK have highlighted an urgent need to develop a national Modified Obstetric Early Warning System (known as MEOWS) to make sure that women who are developing life threatening complications of pregnancy are identified quickly, and referred and treated accordingly. Modified Early Obstetric Warning Charts (MEOWS) assign increasing scores (or colours) to each individual physiological measurement (blood pressure, heart rate, temperature, breathing rate and amount of oxygen in the blood) as they become more abnormal. If either the sum of scores for several physiological measurements, or a score for a single physiological measurement exceed set thresholds, an alert is triggered. We want to develop a database of physiology of pregnancy and the postpartum period (period from just after birth to around 6 weeks after birth) from which an evidence-based, robust early warning score can be developed.

Who can participate?
Pregnant women aged at least 16 without any underlying medical condition known to affect vital signs, that is blood pressure, heart rate, temperature, oxygen saturation levels (amount of oxygen in the blood) and respiratory (breathing) rate.

What does the study involve?
Participants have their vital signs measured by a research midwife at selected points throughout their pregnancy. After pregnancy they are required to carry out home monitoring of their own vital signs using a set of home monitoring equipment for approximately 2 weeks. Each participant is likely to be involved in the study from around 14 weeks of pregnancy to around 14 days postnatal (maximum 30 weeks to allow for women who deliver at 42 weeks). Vital signs data are collected from patients on a monthly basis from their recruitment to the study (at the first routine antenatal appointment or the nuchal scan) to two weeks postpartum. This is a combination of data recorded at regular antenatal visits, any in-hospital stay during pregnancy, delivery and immediately after birth, and data recorded by home monitors in the two weeks immediately after birth. Resting observations for the standard physiological variables used in the current MEOWS charts are recorded from each mother. Demographic, laboratory and medication data which may be related to vital signs is also collected. As a result, a large database of maternal and postpartum physiology will be assembled, from which an evidence-based, national MEOWS will be developed for all stages of pregnancy, the intrapartum (during childbirth) and postpartum periods. A pregnancy stage specific alerting system will be created for use in monitored areas and hospital environments.

What are the possible benefits and risks of participating?
Not provided at time of registration.

Where is the study run from?
The 4P study has been set up by the University of Oxford and runs from The Oxford University Hospitals NHS Trust. Guys and St. Thomas Hospital London and The Newcastle Upon Tyne Hospitals NHS Foundation Trust are in the process of being set up as recruiting sites.

When is the study starting and how long is it expected to run for?
November 2014 to October 2016

Who is funding the study?
Biomedical Research Centre (BRC), Oxford (UK)

Who is the main contact?
Dr Peter Watkinson

Trial website

Contact information



Primary contact

Dr Peter Watkinson


Contact details

The Nuffield Department of Clinical Neurosciences
Oxford University Hospitals NHS Trust
The John Radcliffe Hospital
Headley Way
United Kingdom
+44 (0)1865 857613

Additional identifiers

EudraCT number number

Protocol/serial number

1.0 - 26 June 2014

Study information

Scientific title

The Pregnancy Physiology Pattern Prediction Study (4P Study): an observational cohort study



Study hypothesis

The two most recent Confidential Enquiries into Maternal Deaths in the UK have highlighted an urgent need to develop a national Modified Obstetric Early Warning System (known as MEOWS) to aid the more timely recognition, treatment and referral of women who are developing life-threatening complications of pregnancy. The problem is complicated by the normal changes in maternal physiology that occur both during pregnancy and immediately after delivery. Very limited information exists from which to develop an evidence-based early warning system that is adapted to alert appropriately for the stage of pregnancy or postpartum period.
Although several local Modified Obstetric Early Warning Systems have been developed an evidence-based approach to identifying when women have become physiologically abnormal for their stage of pregnancy is required, to achieve widespread acceptance of a national MEOWS chart.

Ethics approval

NRES Committee South East Coast - Brighton & Sussex; 13/08/2014; ref: 14/LO/1312

Study design

Two year multi-centre prospective observational cohort study

Primary study design


Secondary study design

Cohort study

Trial setting


Trial type


Patient information sheet


Vital signs during pregnancy, intrapartum and two weeks post partum


Vital signs, including oxygen saturation levels, blood pressure, heart rate, respiration rate and temperature will be recorded onto a tablet and smartphone throughout pregnancy at 4-6 week intervals and daily for two weeks in the immediate postpartum period. The recordings are uploaded to a database under the participant's unique study number.

Intervention type


Not Applicable

Drug names

Primary outcome measures

To create a comprehensive database of physiological values during pregnancy, the intrapartum and postpartum periods for 1000 participants.

Secondary outcome measures

1. To develop a centile-based early warning score for pregnancy and the postpartum period.
2. To investigate new patterns within vital signs data in pregnancy

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Over 16 years of age (parental consent to be obtained for participants <18 years old)
2. Pregnant with an intent to deliver in hospital
3. Able to understand written or spoken English or has their own interpreter willing to translate
4. Willing and able to use the home monitoring equipment
5. Within category 1 of the American Society of Anaesthesiologists' classification of physical status at enrolment (normal healthy patient without any clinically important comorbidity and without a clinically significant past/present medical history).

Participant type


Age group




Target number of participants


Participant exclusion criteria

Any known medical condition expected by the recruiting clinician to alter maternal vital signs

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

The Nuffield Department of Clinical Neurosciences
United Kingdom

Sponsor information


University of Oxford (UK)

Sponsor details

c/o Heather House
Head of R&D
Joint Research Office
Block 60
Churchill Hospital
Old Road
United Kingdom

Sponsor type





Funder type

Research council

Funder name

Biomedical Research Council (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes