<prompt> Misoprostol is an analogue ofPGE1PGE2PGF2alfaPGI2  <response>: Misoprostal: PGE-1 Given transvaginally and orally Dose of 25 micrograms every 4 hrs is found to be more effective than PGE -2 for cervical ripening and labor induction. Oral use of misoprostal is less effective than vaginal administration . Ref: Dutta Obs 9e pg 485. 