Labor Induction

Aka: Labor Induction, Pitocin Induction, Pitocin Augmentation, Labor Augmentation

1. See Also
   1. Pitocin
2. Documentation
   1. Indication for Labor Induction
   2. Estimated fetal weight
   3. Fetal Position by ultrasound
   4. Lung maturity for elective induction before 39 weeks
   5. Normal Fetal Assessment
3. Indications
   1. Labor Augmentation
      1. Failure to Progress
   2. Labor Induction
      1. Bishop Score >= 5
         1. See Cervical Ripening for Bishop Score <5
      2. Rupture of Membranes
4. Preparation: Pitocin in Normal Saline
   1. Pitocin 10 units in 1000 ml Normal Saline
      1. Starting rate of 6-12 ml/hour delivers 1-2 mU/minute
      2. Increasing rate 6 ml/hour delivers another 1 mU/min
   2. Pitocin 20 units in 1000 ml Normal Saline
      1. Starting rate of 3-6 ml/hour delivers 1-2 mU/minute
      2. Increasing rate 3 ml/hour delivers another 1 mU/min
5. Protocol: Low Dose
   1. See Monitoring below
   2. Start: 1 mIU/minute
   3. Increase: 1 mU/minute every 15-30 minutes
      1. Base Pitocin rate changes on contractions
      2. After 8 mIU/minute
         1. May then increase by 2 mIU/minute
   4. Maximum: 40 mIU/minute
6. Protocol: High Dose (nulliparous patients only)
   1. See Monitoring below
   2. Start: 6 mIU/minute
   3. Increase: 1-6 mIU/minute every 20 minutes
   4. Maximum: 40-42 mIU/minute
7. Monitoring
   1. Intrauterine pressure catheter
      1. Adequate contraction pattern indicators
         1. Montevideo units >50 mmHg per contraction
         2. Montevideo units 200-300 mmHg per 10 minutes
      2. Observe for signs of hyperstimulation
         1. Fetal Distress
         2. Tetanic contractions
   2. Maternal vital signs
   3. Continuous Electronic Fetal Monitoring (CEFM)
8. Alternative methods
   1. Birth pool as effective as Oxytocin augmentation
      1. Less pain and less use of epidural analgesia
      2. Cluett (2004) BMJ 328:314-8
9. Efficacy
   1. Pitocin is preferred in PROM
      1. Oral mifepristone less effective, more side effects
      2. Wing (2005) Am J Obstet Gynecol 192:445-51
   2. High dose Oxytocin augmentation in nulliparous women
      1. Decrease labor duration by 2 hours without added risk
      2. Merrill (1999) Obstet Gynecol 94:455-63