title: Vaginal misoprostol for term labor induction.
abstract: Misoprostol is an effective agent for cervical ripening and induction of labor. The use of oxytocin was significantly decreased in patients treated with misoprostol versus dinoprostone. It has been used to induce over 1000 women in reported studies and has demonstrated a safety profile comparable with that of endocervical and vaginal dinoprostone. Uterine hyperstimulation was a concern in earlier trials, but at a reduced dose of 25 micrograms, the incidence has decreased to a level that is comparable with the values reported for dinoprostone. Misoprostol tablets are stable at room temperature and are considerably less expensive than the dinoprostone alternatives. Two additional factors pertaining to misoprostol administration must be taken into account before the drug is selected for vaginal use. First, Cytotec tablets are currently available in two strengths, 100 and 200 micrograms. This can lead to confusion or error if the clinician orders a quarter or half tablet. The order should always identify the strength in micrograms (25 or 50 micrograms). Second, the 100-microgram tablet is not scored; therefore, the proper dose should be carefully prepared by a pharmacist using a pill cutter. Key members of the hospital staff must be trained about the proper use of misoprostol for labor induction before initiating therapy. One alternative to directly inserting the tablet is to pulverize it and mix with a gel such as hydroxyethylcellulose gel. However, such compounding introduces the same problems with stability and uniformity of dose as experienced with dinoprostone gels. Despite the success of misoprostol in clinical trials, it is not approved for this indication, and the manufacturer of Cytotec does not plan to pursue approval. Therefore, independent, large-scale studies are warranted to more accurately assess the efficacy and overall safety of using intravaginal alprostadil for cervical ripening and labor induction. Additional clinical experience should also help to determine the best regimen and method of administration. From the data currently available, it appears that either a 25- or 50-microgram dose (one-fourth or one-half of a 100-microgram tablet) inserted into the posterior vaginal fornix and repeated at 4-5-hour intervals if needed, is a clinically effective regimen, and is associated with the least amount of adverse effects and complications. As with all labor inductions, uterine contractions and fetal heart rate should be monitored carefully throughout the procedure.
authors.affiliation: School of Pharmacy, University of the Pacific, Stockton, CA, USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Bauer
authors.forename: D L
authors.initials: DL
authors.lastname: Brown
authors.forename: L K
authors.initials: LK
authors.lastname: Chai
mesh_terms: D000282:Administration, Intravaginal; D003365:Costs and Cost Analysis; D015232:Dinoprostone / Q000008:administration & dosage / Q000191:economics; D005260:Female; D006801:Humans; D007751:Labor, Induced / Q000191:economics; D016595:Misoprostol / Q000008:administration & dosage* / Q000191:economics; D010120:Oxytocics / Q000008:administration & dosage* / Q000191:economics; D011247:Pregnancy
chemical_list: D010120:Oxytocics; D016595:Misoprostol; D015232:Dinoprostone