Induction of Labor

Indications: 

• Post-dates (42+wks) 
• Late Term (41+ wks)
• Elective 39+wks 
• Diabetes
• Hypertension 
• Many more - check out ACOG Medically indicated delivery 

39week induction

ARRIVE Trial - Multicenter RCT showing benefit to 39wk IOL over expectant management to ~41wks 

Included 

• Primips 
• No medical indications for IOL prior to 40+5

 

Results 

• IOL group had LOWER c-section rate than expectant group 
• Neonatal composite outcome had a trend (not statistically significant) toward lower neonatal compilations in IOL group 

Conclusion

• IOL at 39wks is as safe as expectant management without increased risks
• Many pregnant people are now offered a 39wk IOL rather than waiting for spontaneous labor 

The IOL Process: 

 

Evaluate and Prep:

• Full H&P
• Ultrasound for position - Vertex
• VE for cervical exam: dilation/effacement/Station, also position and consistency 
• Calculate Bishops Score → help determine mode of IOL

Options for IOL: if biship score <8 for prime or <6 for multip, ripen first! 

• Mechanical cervical ripening (balloon)
• Chemical cervical ripening (misoprostol or cervidil) 
• Best yet--both! 

 

Contractions (pitocin) 

• Prime: Pitocin alone if Biship 8 or higher
• Mulitp: Pitocin alone if bishop 6 or higher 

 

Augmentation: AROM 

 

Failed IOL

• Failure to reach active labor after 18+hrs ruptured on pitocin (definition varies 12-24hrs ruptured on pitocin) 
• If reaches active labor (6+cm), no longer failed IOL, now arrest of dilation or descent