Maternal mortality in Switzerland 1995-2004

The analysis of maternal mortality is an important instrument for quality assurance in Obstetrics and should be accomplished periodically. This study analysed cases of maternal mortality between 1995 and 2004.

The Federal Statistical Office (BFS) provided all death certificates between 1995 and 2004 with an ICD-10 code in the obstetric field (indicated by the letter O). Additionally, all maternal mortality cases from the archive of the Institute of Legal Medicine (IRM), in Zurich, were investigated. All clinics with a maternal mortality case were asked to fill out a detailed anonymous questionnaire. The cases were classified by ICD-10 in direct, indirect and non-pregnancy-related cases.

This study analysed 50 maternal mortality cases. The mean maternal age was 32 years and 50% had foreign nationality. Haemorrhage (including EUG) was the cause of death in 13 women, nine women died of thromboembolism and six women each of preeclampsia or primary infection. Other causes of death were cerebral bleeding, amniotic fluid embolism and others. We classified 32 cases as direct obstetric deaths, which resulted in a direct maternal mortality ratio of 4.15/100000 live births. Direct maternal mortality associated with caesarean section was 0.06 per thousand (11/177000 caesarean sections [average estimate]) and the underreporting was 20%.

Compared to the prior 10-year-period, the maternal mortality ratio decreased from 5.54 to 4.15. The mortality associated with caesarean section decreased 4.5 times. Women at risk are older mothers and those with a non-Swiss nationality, specifically non-Western nationalities. The most common cause of death in this period was haemorrhage, whereas in the previous period most women died of thromboembolism.