Any value of Early Warning Systems must rely on the prevalence of the conditions being sought

Susan Bewley, Professor of Complex Obstetrics,
September 30, 2013

Mackintosh et al. have made a useful contribution to the literature about pregnant and parturient's safety (1). The purpose of an Early Warning System (EWS) is to take action before deterioration that may require multiorgan support in intensive care. The ethnographic technique revealed many perceived benefits of a simple, graphic monitoring tool that empowered escalation of concerns. The research team highlighted inconsistencies in implementation of EWS, multiple competing charts for antenatal, intrapartum, postnatal and high dependency care and also resistance to medicalising normal birth. However, if EWSs do 'work' (which may yet need proving), their value will also depend on the nature and extent of problems which should not be understated.

The authors state "for every [maternal] death, nine women develop major obstetric complications including haemorrhage, infection, hypertensive disorders and thromboembolism". The RCOG reference cited is itself in error as it reported the numbers of women in the UK utilising critical care settings, (260 vs 14/ 100 000 maternities, a ratio of 19 high dependency and intensive care admissions to each death) (2). The report explains how definitions of severe morbidity vary, but that the number of major obstetric complications may be as high as 86-fold the number of deaths (1 200/ 100 000 maternities) (2,3). EWSs may also have an impact upstream on moderate morbidity with its commoner human and financial costs.


1. Mackintosh N, Watson K, Rance S, Sandall J. Value of a modified early obstetric warning system (MEOWS) in managing maternal complications in the peripartum period: an ethnographic study. BMJ Qual Saf 2013;0:1-9. doi:10.1136/bmjqs-2012-001781

2. Maternal Critical Care Working Group. Providing equity of critical and maternity care for the critically ill pregnant or recently pregnant woman. London: RCOG Press, 2011:4

Conflict of Interest:

None declared

Conflict of Interest

None declared