Labor induction agents

Oxytocin is the most commonly used agent for labor induction after cervical ripening. 

Misoprostol (Cytotec) is a prostaglandin Ej analogue that is being evaluated as a cervical ripening agent. It also is used in the treatment and prevention of peptic ulcer disease (see Chapter 40). Clinical trials show that misoprostol is an effective agent for both cervical ripening and labor induction. It appears to be as effective as dinoprostone and is much less expensive. 

A 34-year-old woman presents for labor induction. Her history is of two prior vaginal deliveries, and examination shows that her cervix is dilated 3 cm and 75% effaced. Which of the following would be the best agent for labor induction ... 

For hundreds of years, a tea brewed from the leaves of Montanoa tomentosa has been used medicinally to induce labor and as an antifertility agent (419, 382). The M. tomentosa extract possessed abortifacient, labor induction, and menstruation induction effects (572, 297). Zoapatanol (55) appears to be the tea component responsible for most of the activity (368). In addition to zoapatanol, several other oxepane diterpenes (56, 57, 1097, 1098, 1099) and their uncyclized precursors (1094, 1095, 1096) were isolated from this species. Commercial interest in these compounds has led to the synthesis of analogous structures sharing similar pharmacological properties (353). 

Prostaglandins have been used intravenously, both for induction of mid-trimester abortion and for induction of labor in cases of intrauterine death. The same adverse effects as described above occur, and are usually very pronounced. Routine premedication with an antiemetic and an antidiarrheal agent significantly reduces gastrointestinal adverse effects. 

Prostaglandin E2 (PGE2) is an agent used to ripen the cervix for the induction of labor (it is also used for second-trimester abortion) and shows various beneficial effects ... 

Thumbnail Uterotonic Agents Used for Induction of Labor... 

Adverse reactions In induction of labor, both of these uterotonic agents can cause too frequent contractions, leading to uterine hypertonus, tetanic contractions, fetal distress, and uterine rupture. 

Misoprostol is a prostaglandin analog used in the therapy of ulcers. It is also used as a contractile agent in the induction of labor. 

Significant side effects are those associated with its abortifacient properties and other smooth muscle contraction effects, e.g., diarrhea and abdominal pain. Misoprostol also is an effective cervical ripening agent (by vaginal application) for the induction of labor. Other unlabeled uses include the treatment of postpartum hemorrhage and, with mifepristone, termination of pregnancy. 

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