## Prostaglandin Analogs for Labor Induction **Key Point:** Misoprostol is the most widely used prostaglandin analog for cervical ripening and labor induction globally and in India due to its low cost, stability at room temperature, and ease of administration. ### Comparison of Prostaglandins | Agent | Type | Route | Onset | Stability | Cost | Use in India | |-------|------|-------|-------|-----------|------|---------------| | **Misoprostol** | PGE1 analog | Oral, vaginal, sublingual | 30 min | Room temperature | Very low | Most common | | Dinoprostone | PGE2 | Vaginal gel, insert | 30 min | Requires refrigeration | High | Limited | | Carboprost | 15-methyl PGF2α | IM | 15 min | Room temperature | Moderate | Uterotonic only | | Sulprostone | PGE1 analog | IV, IM | Rapid | Requires refrigeration | High | Rare | **High-Yield:** Misoprostol dosing for cervical ripening: - **Oral:** 25 mcg every 3–6 hours - **Vaginal:** 25 mcg every 3–6 hours (or 50 mcg once daily) - **Sublingual:** 25 mcg every 3–6 hours **Clinical Pearl:** Dinoprostone requires refrigeration and is significantly more expensive, making it impractical in resource-limited settings. Carboprost is reserved for management of postpartum hemorrhage, not cervical ripening. **Warning:** Misoprostol is contraindicated in women with prior uterine scar (classical cesarean section) due to increased risk of uterine rupture; however, it is relatively safe in lower-segment transverse scar cesareans with careful monitoring. ### Mechanism Prostaglandins promote cervical ripening by: 1. Increasing collagenase activity → collagen degradation 2. Increasing hyaluronic acid and water content in cervical stroma 3. Stimulating uterine contractions via increased intracellular calcium [cite:Williams Obstetrics 26e Ch 21]
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.