Swiss Obstetric Surveillance System (Swiss.OSS)

The Swiss Obstetric Surveillance System (Swiss.OSS) operates as an Enhanced Obstetric Surveillance System, involving a voluntary participation of all maternity units across Switzerland. Its primary objective is to study severe maternal outcome in Switzerland to improve the quality of maternity care throughout the country. The Swiss obstetric surveillance system is coordinated by the Department of Gynecology and Obstetrics, Lausanne University Hospital and University of Lausanne. (Swiss Chair: P.L.M. de Vries. Contact: pauline.de-vries@chuv.ch)

Mission statement

To provide estimates on several indicators of severe maternal outcome, identify key factors contributing to severe maternal outcome, and promote targeted public health interventions to improve the quality of maternity care and prevent avoidable adverse maternal outcomes.

Aims

1. To characterize the occurrence of predefined indicators of severe maternal outcome and their evolution over time in Switzerland
2. To identify the main causes of maternal mortality through active declaration by all maternity units in Switzerland to our register
3. To analyze the circumstances of occurrence and management of the morbid events in order to identify areas for improving maternal care in Switzerland
4. To compare the occurrence of morbid events and the performance of our healthcare system with other high-resource countries
5. To formulate evidence-based recommendations and lessons learned for clinical practice
6. To conduct prospective national and cross-country studies with regard to specific research questions on severe maternal outcome

Monitoring severe maternal outcome in Switzerland

Swiss.OSS has been founded in 2024 and operates through active declaration of predefined indicators of severe maternal outcome by all maternity hospitals in Switzerland to a central database. All cases are assessed by a confidential enquiry to determine the cause of the event, classify its preventability and identify elements of substandard care to provide lessons learned. Based on the findings of the confidential enquiry, a report is prepared every two years including national recommendations and lessons learned for maternity care workers and stakeholders.

Current studies

Swiss.OSS is currently conducting prospective population-based research projects on the following conditions:

• severe maternal morbidity due to obstetric hemorrhage (peripartum hysterectomy)
• severe maternal morbidity due to eclampsia and amniotic fluid embolism