We thank Patrick Maguire and Michael Turner for their comments on our work on modified obstetric early warning scoring systems (MOEWS) for the prediction of severe maternal sepsis. We agree that the interpretation of our findings is limited by the fact that early recognition of sepsis and appropriate treatment may have prevented some cases from developing severe sepsis and triggering the early warning system; this is a practical limitation of all ethical studies on sepsis management and outcomes. However within our population of women with sepsis, we would still expect the MOEWS to trigger its highest alert for cases that did indeed develop severe sepsis. Our analysis highlighted that all the MOEWS tested tended to overdiagnose severe sepsis, and more worryingly the sickest patients did not reach alert levels using some MOEWS. As we highlighted in our discussion, the wide variation in performance of MOEWS for sepsis is concerning.

We welcome Dr Maguire and Prof Turner’s work to develop the Irish Maternity Early Warning System (IMEWS), and recognize their important success in improving recording of vital signs associated with use of this system. Unfortunately as their publication, including a description of this national MOEWS, was published after our study, it was not possible to include their IMEWS in our analysis.

Their article and ours both recognize that accurate and timely documentation of observations is essential to improving the recognition and prompt management of sepsis; and that the use of MOEWS, including IMEWS, may be an extremely useful first step.

However, we maintain that further validation studies are needed to assess whether MOEWS utilization results in improved maternal outcomes (and not simply increased recording of vital sign data). While false alarms are expected given that severe maternal illness is uncommon, early warning systems that do not result in improved outcomes potentially: (1) expose women to interventions that may be unnecessary and/or cause harm; and (2) cause “alarm fatigue,” resulting in provider or unit desensitization, mistrust, and lack of response, which could further jeopardize women with evolving severe clinical illness.