Effect of vacuum curettage on the concentrations of plasma 6-keto-prostaglandin F1 alpha and serum thromboxane B2.

Serial plasma samples collected before and after vacuum curettage followed by methylergometrine injection in 10 women were assayed for 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha). The mean 6-keto-PGF1 alpha concentration was 97.2 (SE 8.8) pg/ml before cervical dilatation. The concentration rose to 128.2 (SE 13.5) pg/ml (P less than 0.10) immediately and to 133.3 (SE 17.8) pg/ml (P less than 0.05) 1 h after curettage and returned to the initial value within 5 h. Neither methylergometrine nor anaesthesia, nor non-gynaecological surgery, caused changes in the level of plasma 6-keto-PGF1 alpha. The capacity of the platelets to produce thromboxane A2 during spontaneous clotting of blood did not change during vacuum curettage, anaesthesia and non-gynaecological surgery, nor after methylergometrine. The evidence suggests that the pregnant myometrium and/or intrauterine tissues capable of generating prostacyclin (PGI2) in vitro may release PGI2 also in vivo.