Effect of ibuprofen on menstrual blood prostaglandin levels in dysmenorrheic women.

In a randomized crossover study 15 dysmenorrheic women were treated during two consecutive menstrual period, once with the potent prostaglandin-synthesis inhibitor: ibuprofen and once with an identical looking placebo. Each patient was medicated for 12 hours during the first day of her menstrual flow and was subsequently fitted with a cervical cup for the collection of menstrual blood during three hours. In these samples the concentrations of prostaglandin (PG)F and PGE were measured by radioimmunoassay. The patients receiving placebo had high PGF levels 135 +/- 27 ng/ml (Mean +/- S.E.) which were significnatly reduced by Ibuprofen to 24 +/- 5 ng/ml (P less than 0.001). The PGE concentrations decreased from 5 +/- 1 ng/ml to 2 +/- 1 ng/ml (P less than 0.05). Ibuprofen also reduced the menstrual pain significantly (P less than 0.001). These results substantiate the earlier conclusion that a causal relationship exists between effective treatment with PG-synthesis inhibitors and decrease in menstrual blood PG levels, intrauterine pressure and dysmenorrheic pain.