Thirty-eight cases of puerperal thrombophlebitis were reported. The incidence was 0.36% for the 1960s and 0.38% for the 1970s. During 1980s, it was reduced to 0.11%. However, the severity of the disease remained unimproved. Pulmonary and cerebral embolism occurred each in one case. Cesarean section was found to be associated with a 3-19 times increase of risk of developing puerperal thrombophlebitis as compared with vaginal delivery. The pathophysiological changes, diagnostic methods, treatment and prevention are discussed.