Background: Although pulmonary thromboembolism (PTE) has been considered relatively uncommon in Japan, its incidence has been on the increase in recent years.
Methods and results: To verify the incidence of PTE in Japan, PTE cases of obstetrics and gynecology were investigated among 102 facilities throughout Japan between 1991 and 2000. A total of 254 cases were enrolled, showing a 6.5-fold increase over the past 10 years. PTE occurred in 0.02% of total births; 0.003% after vaginal deliveries and 0.06% after cesarean births (C/S), of which 14.5% resulting in fatality. The mortality rate was 2.5 per 100,000 deliveries. The incidences among gynecological cases were 0.08% of total operations; 0.03% in benign diseases and 0.42% in malignant diseases of which 13.5% resulting in fatality. The mortality rate was 10.8 per 100,000 operations. The risk was 22 times higher in C/S compared with vaginal deliveries, 16 times higher in malignant diseases compared with benign diseases.
Conclusions: As our present survey has shown, PTE has been on the rise in Japan in recent years. C/S and malignant diseases are strong risk factors in obstetrics and gynecology.