trimester

9-deoxy-9-methylene-16,16-dimethyl Prostaglandin E2 (Meteneprost) is a potent analog of prostaglandin E2 with an extended half-life in vivo. In combination with various other prostaglandin derivatives, it results in the termination of first trimester pregnancy in monkeys. A single intramuscular injection containing 0.5 mg of meteneprost and 7.5 mg of 17-phenyl trinor PGF1α is very effective in terminating early pregnancy. This prostaglandin mixture is ineffective on monkeys in their third trimester of pregnancy. Meteneprost, when compared to PGE2 and PGF1α, in monkey and rat, does not result in unwanted side effects such as fever or gastrointestinal problems.

17α-Hydroxyprogesterone (17-OHP) is a physiological progestin that is produced during glucocorticoid and steroid hormone synthesis and is increased during the third trimester of pregnancy. Hydroxyprogesterone binds to the cytoplasmic progesterone receptors in the reproductive system and subsequently activates progesterone receptor-mediated gene expression.

Carboprost (15(S)-15-Methyl Prostaglandin F2α) is a synthetic analogue of PGF2α with oxytocic properties, commonly used to restore uterine tone.

13,14-dihydro-15-keto Prostaglandin E2 (13,14-dihydro-15-keto PGE2) serves as the predominant metabolite of PGE2 in plasma, created through a 15-keto PGE2 intermediate by the action of 15-oxo-PG Δ13 reductase. Unlike its precursor PGE2, this compound exhibits poor binding affinity towards EP2 and EP4 PGE2 receptors (Ki values of 12 and 57 µM, respectively) in CHO cells and fails to stimulate adenylate cyclase activity therein (EC50s >18 and >38 µM, respectively). Concentrations of 13,14-dihydro-15-keto PGE2 are notably higher in the plasma of pregnant women during their third trimester and at labor and delivery stages, whereas its levels are found to be reduced in the tumor tissues of patients with non-small cell lung cancer (NSCLC) compared to adjacent healthy tissue.

17α-Hydroxyprogesterone acetate is a compound with progestational activity and exhibits anti-inflammatory effects at the murine maternal-fetal interface.

17α-Hydroxyprogesterone-d8 is a deuterated compound of 17α-Hydroxyprogesterone.