Increase in maternal death-related venous thromboembolism during pregnancy in Japan (2010-2013)

The aim of the present work was to understand the current circumstances of maternal-death-related venous thromboembolism (MD-VTE) in Japan. We retrospectively investigated the characteristics of cases of MD-VTE, and compared past and present rates of occurrence.

We examined the Japanese data for MD-VTE in 2010-2013, and compared it with that from 1991-1992. MD-VTE occurred in 17 women in 1991-1992, and in 13 women in 2010-2013. The maternal mortality ratio of MD-VTE was 0.7 per 100,000 in 1991-1992 and 0.4 per 100,000 in 2010-2013. Both the maternal mortality ratio and rate of MD-VTE in 2010-2013 deceased significantly compared with 1991-1992 (P<0.05). However, the number of cases of MD-VTE during pregnancy was 6 among 13 women (41%) in 2010-2013, but 1 in 17 women (6%) in 1991-1992, showing an increase (P<0.05). In the present study, cesarean delivery was more frequently associated with MD-VTE.

MD-VTE overall has decreased within the past 20 years in Japan. But, MD-VTE during pregnancy in 2010-2013 increased relative to 1991-1992. Future guidelines for prevention of VTE may need to extend beyond the perioperative period to decrease the incidence of MD-VTE.