Maternal Mortality in Taiwan: A Nationwide Data Linkage Study.

Background: To examine the changes in the maternal mortality ratio (MMR) and causes of maternal death in Taiwan based on nationwide linked data sets.

Methods: We linked four population-based data sets (birth registration, birth notification, National Health Insurance inpatient claims, and cause of death mortality data) to identify maternal deaths for 2004-2011. Subsequently, we calculated the MMR (deaths per 100,000 live births) and the proportion of direct and indirect causes of maternal death by maternal age and year.

Findings: Based on the linked data sets, we identified 236 maternal death cases, of which only 102 were reported in officially published mortality data, with an underreporting rate of 57% [(236-102) × 100 / 236]. The age-adjusted MMR was 18.4 in 2004-2005 and decreased to 12.5 in 2008-2009; however, the MMR leveled off at 12.6 in 2010-2011. The MMR increased from 5.2 in 2008-2009 to 7.1 in 2010-2011 for patients aged 15-29 years. Women aged 15-29 years had relatively lower proportion in dying from direct causes (amniotic fluid embolism and obstetric hemorrhage) compared with their counterpart older women.

Conclusions: Approximately two-thirds of maternal deaths were not reported in officially published mortality data. Routine surveillance of maternal mortality by using enhanced methods is necessary to monitor the health status of reproductive-age women. Furthermore, a comprehensive maternal death review is necessary to explore the preventability of these maternal deaths.