Variation in stillbirth rates across high-income countries and large equity gaps within high-income countries persist. If all high-income countries achieved stillbirth rates equal to the best performing countries, 19 439 late gestation (28 weeks or more) stillbirths could have been avoided in 2015. The proportion of unexplained stillbirths is high and can be addressed through improvements in data collection, investigation, and classification, and with a better understanding of causal pathways. Substandard care contributes to 20-30% of all stillbirths and the contribution is even higher for late gestation intrapartum stillbirths. National perinatal mortality audit programmes need to be implemented in all high-income countries. The need to reduce stigma and fatalism related to stillbirth and to improve bereavement care are also clear, persisting priorities for action. In high-income countries, a woman living under adverse socioeconomic circumstances has twice the risk of having a stillborn child when compared to her more advantaged counterparts. Programmes at community and country level need to improve health in disadvantaged families to address these inequities.

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. Funding HR, SH, SHL, and AW were supported by an NHMRC‐CRE grant (APP1116640). VF was funded by an NHMRC‐CDF (APP1123611). Tweetable abstract Urgent need to improve data on causes of stillbirths across all settings to meet global targets. Plain Language Summary Background and methodsNearly three million babies are stillborn every year. These deaths have deep and long‐lasting effects on parents, healthcare providers, and the society. One of the major challenges to preventing stillbirths is the lack of information about why they happen. In this study, we collected reports on the causes of stillbirth from high‐, middle‐, and low‐income countries to: (1) Understand the causes of stillbirth, and (2) Understand how to improve reporting of stillbirths. FindingsWe found 85 reports from 50 different countries. The information available from the reports was inconsistent and often of poor quality, so it was hard to get a clear picture about what are the causes of stillbirth across the world. Many different definitions of stillbirth were used. There was also wide variation in what investigations of the mother and baby were undertaken to identify the cause of stillbirth. Stillbirths in all income settings (low‐, middle‐, and high‐income countries) were most frequently reported as Unexplained, Other, and Haemorrhage (bleeding). Unexplained and Other are not helpful in understanding why a baby was stillborn. In low‐income countries, stillbirths were often attribute...