Dinoprostone is a naturally occurring prostaglandin E2 (PGE2). Dinoprostone is equivalent to prostaglandin E2 (PGE2). It stimulates labor and delivery by stimulating the uterine, and thus terminates pregnancy. Dinoprostone is also capable of stimulating the smooth muscle of the gastrointestinal tract of man. This activity may be responsible for the vomiting and/or diarrhea that is not uncommon when dinoprostone is used to terminate pregnancy. Dinoprostone administered intravaginally stimulates the myometrium of the gravid uterus to contract in a manner that is similar to the contractions seen in the term uterus during labor, resulting in the evacuation of the products of conception from the uterus. It is believed that dinoprostone exerts its uterine effects via direct myometrial stimulation. It is used for the termination of pregnancy during the second trimester (from the 12th through the 20th gestational week as calculated from the first day of the last normal menstrual period), as well as for evacuation of the uterine contents in the management of missed abortion or intrauterine fetal death up to 28 weeks of gestational age as calculated from the first day of the last normal menstrual period. Also used in the management of nonmetastatic gestational trophoblastic disease (benign hydatidiform mole). Other indications include improving the cervical inducibility (cervical "ripening") in pregnant women at or near term with a medical or obstetrical need for labor induction, and the management of postpartum hemorrhage.

8-Iso-prostaglandin E2 (8-iso-PGE2) is one of the several isoprostanes produced from arachidonic acid during lipid peroxidation. Isoprostanes are a group of stable prostaglandin-like compounds produced by free radical-catalyzed, non-enzymatic peroxidation of arachidonic acid, which are used as markers of oxidative stress in several human diseases, including diabetes. In addition, 8-iso-prostaglandin E2 is biologically active compound involved in contraction of vascular smooth muscle and activation of platelets. 8-iso-PGE2 has been demonstrated to be the most potent vasoconstrictor isoprostane on the human umbilical artery and vein, activating the TPα isoform, which is present in the human umbilical vein and platelets. 8-iso-prostaglandin E2 stimulates human umbilical vein endothelial cells to specifically bind monocytes and this effect is mediated by cyclic AMP/protein kinase A- and p38 MAP kinase-dependent pathways and is independent of the classical inflammatory NFkappaB pathway.