Prostaglandins, indomethacin and dysmenorrhea.

Uterine contractility was recorded during the period of menstruation in six dysmenorrheic women. A variable high tonus was observed in each case. Uterine recordings were repeated during the subsequent menstruation following pre-treatment with indomethacin at an oral dose of 75 mg or 200 mg per day beginning one day before the expected onset of menstruation. A lower uterine tonus was found in all indomethacin-treated cycles. Complete alleviation of spasmodic pain was obtained in the six subjects. The endogenous concentration of 15-keto-13, 14-dihydro PGF2alpha was determined by the gas chromatography-mass spectrometry method and observed to be relatively high in women with dysmenorrhea.