| Australia |
Australasian Maternity Outcomes Surveillance System (AMOSS). [35] |
National obstetric surveillance system. Collected data from hospitals with more than 50 births per year. |
One year (July 2014-June 2015) |
| Denmark |
Danish Medical Birth Registry and the Danish Transfusion Database |
Routinely collected national data on both birth and transfusions. |
Five years (2010–2015) |
| France |
Épidémiologic de la Morbidité Maternelle Sévère study (EPIMOMS) [36] |
Prospective Population-based study from all maternity units in 6 regions. |
One year (2012–2013) |
| Italy |
Italian Obstetric Surveillance System (ItOSS) |
Population-based study from all maternity units in 6 regions in Italy. |
Two years (September 2014-August 2016) |
| The Netherlands |
Transfusion strategies in women during Major Obstetric Haemorrhage study (TeMpOH-1) [37] |
Collected data from 75% of national births |
Two years (January 2011 and January 2013) |
| United Kingdom |
United Kingdom Obstetric Surveillance System (UKOSS) [38] |
Obstetric surveillance system which collected data nationally from all consultant-led hospitals. |
One year (June 2013- July 2014) |
