Maternal Death due to Complications Related to Labor Analgesia: Report From Maternal Death Exploratory Committee in Japan

Objectives: To clarify the causes of maternal death due to complications related to labor analgesia. Methods: A nationwide retrospective study was conducted to investigate intrapartum maternal deaths in Japan between 2010 and 2022. The obstetric and anesthetic characteristics of women with (cases) and without (controls) labor analgesia were compared. Results: Of the 558 maternal deaths in Japan during the study period, 161 occurred intrapartum. Among these, 24 (15%) patients received labor analgesia (cases), 117 did not receive labor analgesia (controls), and 20 underwent elective cesarean section. Regarding the causes of maternal death, the incidence of amniotic fluid embolism was 71% among the cases and 56% among the controls. The incidence of uterine rupture/laceration was 13% among the cases and 9% among the controls (nonsignificant difference). Moreover, among the patients who received labor analgesia, there were two cases of maternal deaths directly related to neuraxial labor analgesia (due to high spinal anesthesia and local anesthetic toxicity). Induction of labor was attempted in 96% of the cases with labor analgesia compared to 55% of the controls (p < 0.01). Conclusion: Among the cases of maternal deaths, amniotic fluid embolism, uterine rupture/laceration, and complications of the labor analgesia itself were likely causes in patients who had received labor analgesia. These results may be related to the higher frequency of induction of labor in labor analgesia.