Abstract: | To extend observations in 11 weeks pregnant patients the mechanism of prostaglandin (PG) action has been examined in 6 weeks pregnant women (LMP). In 10 gravidas menstrual induction was attempted with a single slow release vaginal suppository containing 3000 microgram (155)-methyl PGF2 alpha methyl ester (U-36,384). In 10 additional gravidas menstruation was provoked by the intramuscular injection of 500 microgram 16-phenoxy-omega-tetranor PGE2 methyl sulfonylamide (Sulproston) at 4 hour intervals, totalling 1250 +/- 154 microgram. The PGF2 alpha and PGE2-analogues provoked similar changes in hormone levels and uterine function, sequentially measured by radioimmunoassays and the recording of intrauterine pressure. However, the effects of the intramuscular regimen developed earlier. Both treatments successfully terminated early pregnancy with clinical symptoms of menstruation if they irreversible compromised the conceptus within 12 hours. However, while both formulations represent advances in postconceptional therapy, only further modifications may closely approximate the "ideal" method of non-surgical menstrual induction. |