Additional file 1: PRISMA checklist. ; Additional file 2: Decision tree for inclusion/exclusion. ; Additional file 3: List of variables extracted. ; Additional file 4: Sensitivity of number of “widely used” systems to cut-offs for number of countries in which used and number of deaths classified. ; Additional file 5: All included publications with reason for inclusion and author intent. ; Additional file 6: Year of creation/modification of classification systems for causes of stillbirth and neonatal death developed or used between 2009 and 2014. ; Additional file 7: Countries in which more than one system was used to classify causes of stillbirths and/or neonatal deaths, 2009-2014. ; Additional file 8: National classification systems for causes of stillbirth and neonatal death in use 2009-2014. ; Additional file 9: Classification systems for causes of stillbirth and neonatal death used in highest-burden countries, 2009-2014. ; Additional file 10: Maximum percent of deaths classified as “other” and “unexplained” by classification systems according to type of death classified. ; Additional file 11: Kappa scores from reliability testing of classification systems for causes of stillbirth and neonatal death in use 2009-2014. ; Additional file 12: Selected shortcomings of existing systems and rationale for development of new systems/modification of existing systems. ; BACKGROUND : Each year, about 5.3 million babies die in the perinatal period. Understanding of causes of death is critical for prevention, yet there is no globally acceptable classification system. Instead, many disparate systems have been developed and used. We aimed to identify all systems used or created between 2009 and 2014, with their key features, including extent of alignment with the International Classification of Diseases (ICD) and variation in features by region, to inform the World Health Organization’s development of a new global approach to classifying perinatal deaths. METHODS : A systematic literature review (CINAHL, EMBASE, Medline, Global Health, and PubMed) identified published and unpublished studies and national reports describing new classification systems or modifications of existing systems for causes of perinatal death, or that used or tested such systems, between 2009 and 2014. Studies reporting ICD use only were excluded. Data were independently double-extracted (except from non-English publications). Subgroup analyses explored variation by extent and region. RESULTS : Eighty-one systems were identified as new, modifications of existing systems, or having been used between 2009 and 2014, with an average of ten systems created/modified each year. Systems had widely varying characteristics: (i) comprehensiveness (40 systems classified both stillbirths and neonatal deaths); (ii) extent of use (systems were created in 28 countries and used in 40; 17 were created for national use; 27 were widely used); (iii) accessibility (three systems available in e-format); (iv) underlying cause of death (64 systems required a single cause of death); (v) reliability (10 systems tested for reliability, with overall Kappa scores ranging from .35–.93); and (vi) ICD alignment (17 systems used ICD codes). Regional databases were not searched, so system numbers may be underestimated. Some non-differential misclassification of systems was possible. CONCLUSIONS : The plethora of systems in use, and continuing system development, hamper international efforts to improve understanding of causes of death. Recognition of the features of currently used systems, combined with a better understanding of the drivers of continued system creation, may help the development of a truly effective global system. ; The Mater Research Institute, University of Queensland, Australia, funded VF, and partially funded HR, AW, and SHL, and TZ as part of the University of Queensland undergraduate student scholarship, to undertake this study. ; http://www.biomedcentral.com/bmcpregnancychildbirth ; am2016 ; Obstetrics and Gynaecology