Effects of a new antiovulatory steroid on gonadotropins, prolactin and blood coagulation

Ro 6-5403* * Ro 6-5403; Hoffmann-LaRoche AG. Grenzach, Federal Republic of Germany. a potent gonadotropin inhibitor with extremely weak estrogen-like activity in rats, was given to 8 normally menstruating women who had previously undergone tubal ligation. The volunteers were investigated during 3 consecutive menstrual cycles. The drug was administered orally in the second cycle on days 5 through 24 at a daily dose of 4 mg. Blood was withdrawn at 1-5 day intervals during each cycle. Inhibition of release of LH and FSH and low progesterone levels in plasma indicated suppression of ovulation during the treatment period. Plasma prolactin levels were found to be significantly (P < 0.001) elevated during treatment. Blood coagulation parameters and thromboelastography showed a definite tendency toward 'hypercoagulability', even during this single treatment cycle; plasma fibrinolytic activity remained within the normal range. Some minor side effects, such as nausea, loss of appetite and painful venous congestion in the lower extremities were reported during treatment. Liver and kidney functions were not affected. Elevated prolactin levels as well as 'hypercoagulability' were interpreted to be related to the estrogen-like activity inherent to the drug. © 1975.SCOPUS: ar.j