Local effect of progesterone on prostaglandin F2a-levels in menstrual blood. (Abstract only).

Clinical findings suggest a relationship between prostaglandins of the F2a group progesterone and dysmenorrhea. The menstrual flow of 5 dysmenorrhoic women aged 20-30 years was collected 2 cycles with and 2 cycles without local intrauterine administration of progesterone (Progestasert). Menstrual blood was collected by tampons which were stored in butyl alcohol saturated with water. Prostaglandins were extracted by ethyl acetate and methanol. The extracts were purified with petrol ether and ethyl acetate:isopropyl alcohol:.1 n HC1 3:3:1 (v/v/v). Prostaglandin F2a was determined by radioimmunoassay. Reliability criteria were assessed: Precision: .052 + or - .00972 standard error of the mean (n=72). Sensitivity: 2.5 pg. Specificity: PGF2 100% - PGF1 38% - 1 all the other prostaglandins and metabolites 1% cross-reaction. Intraassay coefficient of variation 14.01%. The recovery of the method was 85.3%; parallelity was significant. PGF2a production rate of the menstrual bleedings was 7468.04 ng + or - 1670.90 standard deviation (SD; n=9). The 1st treatment cycle did not differ significantly from control levels (5672.30 ng + or -2138.40 SD n=5). After the local intrauterine administration of progesterone (Progestasert) the PGF2a content falls to 1470.88 ng + or -35150 SD (n=5) during the 2nd menstrual bleeding. This difference is highly significant (p less than .05). Furthermore we have found a significant difference in the PGF2a concentration per ml menstrual blood between the control cycle and the 2nd cycle after insertion of Progestasert. These data conform to the clinical results and imply that endometrial prostaglandin synthesis is under progesterone control. (Full text)