Pelvic congestion may cause chronic pelvic pain in women. The aim of the study is to elucidate a possible role in this condition for prostaglandin. Prostaglandin levels in peritoneal fluid were measured in 18 women with pelvic pain caused by pelvic congestion following sterilization, 10 women without pain following sterilization, and 10 normal healthy women. Peritoneal fluid was aspirated by a silastic catheter from the cul-de-sac under laparoscopic direct vision. Concentration of 6-keto-PGF1 alpha, TXB2, PGF2 alpha and PGE2 were measured with the standard radioimmunoassay method in all samples. Results showed that 6-keto-PGF1 alpha levels in peritoneal fluid from patients with pelvic congestion were markedly higher than those from two control women (P < 0.05); 6-keto-PGF1 alpha/TXB2 in pelvic congestion and control groups were markedly different (P < 0.05); the total amounts of peritoneal fluid was higher in pelvic congestion than that in two control groups (P < 0.001). These data suggested that 6-keto-PGF1 alpha is increased in peritoneal fluid of women with pelvic congestion and the change might play an important role in attack of this disease.