Data extraction
The following data were extracted into pre-piloted forms where available: period of data collection, country, setting (population/national, multicentre hospital, or single centre hospital), study design, mean maternal age, mean gestational age, total number of births, total number of stillbirths, stillbirth rate, stillbirth definition, stillbirth classification system used, proportion of stillbirths classified, data source, examination rate (autopsy, placental histology), and cause of stillbirth. Discrepancies were resolved by consensus or by involvement of a third independent reviewer (SMB). Missing data were reported as such and any corresponding authors were contacted for unclear information.