Background In countries such as the UK where maternal deaths are rare, reviews of other severe complications can provide an additional perspective to help learn lessons to improve future care. The aim of this study was to identify the types of incidents which triggered local reviews in UK maternity units in order to inform future guidance for confidential case reviews of severe maternal morbidities.

Methods All consultant-led maternity units in the UK were contacted up to three times and asked to supply a copy of the checklist of incidents which triggered a local review. The lists were tabulated and compared with incidents recommended for review by the Royal College of Obstetricians and Gynaecologists (RCOG).

Results Among the 211 consultant-led maternity units in the UK, 72% provided an incident review trigger list. The conditions covered were highly variable, although those recommended by the RCOG were most highly represented. Over 90% of units who responded included maternal and neonatal deaths, stillbirths, intensive care admissions, severe haemorrhage (>1500 ml) and shoulder dystocia. Between 80–90% of units also listed eclampsia, uterine rupture, medication error and other organisational incidents. Only 73% of units listed hysterectomy, 66% cardiac arrest and 62% maternal sepsis or a severe infection.

Conclusions Significant variation exists between units in the number and type of conditions reviewed. Importantly, less than two thirds of units specifically review cases of severe infective complications, despite current concerns about a rising rate of maternal death due to sepsis.