Background: Stillbirth is a global health problem. The World Health Organization (WHO) application of the International Classification of Diseases for perinatal mortality (ICD‐PM) aims to improve data on stillbirth to enable prevention.

Objectives: To identify globally reported causes of stillbirth, classification systems, and alignment with the ICD‐PM.

Search strategy: We searched CINAHL, EMBASE, Medline, Global Health, and Pubmed from 2009 to 2016.

Selection criteria: Reports of stillbirth causes in unselective cohorts.

Data collection and analysis: Pooled estimates of causes were derived for country representative reports. Systems and causes were assessed for alignment with the ICD‐PM. Data are presented by income setting (low, middle, and high income countries; LIC, MIC, HIC).

Main results: Eighty‐five reports from 50 countries (489 089 stillbirths) were included. The most frequent categories were Unexplained, Antepartum haemorrhage, and Other (all settings); Infection and Hypoxic peripartum (LIC), and Placental (MIC, HIC). Overall report quality was low. Only one classification system fully aligned with ICD‐PM. All stillbirth causes mapped to ICD‐PM. In a subset from HIC, mapping obscured major causes.

Conclusions: There is a paucity of quality information on causes of stillbirth globally. Improving investigation of stillbirths and standardisation of audit and classification is urgently needed and should be achievable in all well‐resourced settings. Implementation of the WHO Perinatal Mortality Audit and Review guide is needed, particularly across high burden settings.