Which drug acts to terminate pregnancy by stimulating uterine contractions via prostaglandin action?

Which drug acts to terminate pregnancy by stimulating uterine contractions via prostaglandin action?

• A. Leuprolide
• B. Zidovudine
• C. Misoprostol
• D. Mifepristone

Answer: (C)

Prostaglandins promote uterine contractions to expel pregnancy tissue. Misoprostol is a synthetic prostaglandin E1 analog that binds uterine prostanoid receptors, increasing calcium in myometrial cells and triggering rhythmic contractions plus cervical ripening. This direct prostaglandin action makes it effective for medical abortion, either alone or following mifepristone, which helps by detaching the conceptus but does not itself induce contractions via prostaglandins. The other drugs work through different mechanisms: leuprolide suppresses gonadotropins, zidovudine is an antiviral, and mifepristone blocks progesterone signaling rather than stimulating prostaglandin-mediated contractions.

Prostaglandins promote uterine contractions to expel pregnancy tissue. Misoprostol is a synthetic prostaglandin E1 analog that binds uterine prostanoid receptors, increasing calcium in myometrial cells and triggering rhythmic contractions plus cervical ripening. This direct prostaglandin action makes it effective for medical abortion, either alone or following mifepristone, which helps by detaching the conceptus but does not itself induce contractions via prostaglandins. The other drugs work through different mechanisms: leuprolide suppresses gonadotropins, zidovudine is an antiviral, and mifepristone blocks progesterone signaling rather than stimulating prostaglandin-mediated contractions.