15(S)-15-methyl PGF2α is a metabolically stable analog of PGF2α. It is a potent uterine stimulant and abortifacient which can be administered intramuscularly to induce labor.{4695,1608,1587} It induces luteolysis and reduces serum progesterone concentrations when given as an intramuscular injection in non-pregnant rhesus monkeys.{4632}