BACKGROUND AND PURPOSE:

• Jones et al. (The Lancet, 2022) compared the effectiveness and safety profiles of balloon catheters vs vaginal prostaglandins for cervical ripening

METHODS:

• Individual participant data meta-analysis
• Study inclusion criteria
  • RCTs
  • Studies that compared balloon catheter with vaginal prostaglandins for cervical ripening
• Study design
  • Investigators associated with eligible trials approached to share participant-level data
    • Data subsequently harmonized and recoded based upon predefined definitions of variables
    • Main analysis was by intention to treat
    • Primary meta-analysis used random-effects models
  • All models were adjusted for maternal age and parity
• Primary outcomes
  • Cesarean delivery
  • Indication for cesarean delivery
  • A composite adverse perinatal outcome
  • A composite adverse maternal outcome

RESULTS:

• 12 studies (original data available) | 43 studies did not share data
  • 5460 participants
• Prostaglandin groups
  • PGE2 (dinoprostone): 8 trials
  • PGE1 (misoprostol): 3 trials
  • Both PGE1 and PGE2: 1 trial
• Balloon groups
  • Single balloon: 8 trials
  • Double balloon: 3 trials
  • Both options: 1 trial
• There was no significant difference in the rate of cesarean delivery
  • Cesarean delivery
    • Crude incidence 27.0%
    • Adjusted odds ratio (aOR) 1.09 (95% CI, 0.95 to 1.24)
    • 12 trials | 5414 women
  • Cesarean delivery for failure to progress
    • aOR 1.20 (95% CI, 0.91 to 1.58)
    • 11 trials | 4601 women
  • Cesarean delivery for fetal distress
    • aOR 0.86 (95% CI, 0.71 to 1.04)
    • 10 trials | 4441 women
• The composite adverse perinatal outcome was lower in women who were allocated to balloon catheters
  • Crude incidence 13.6%
  • aOR 0.80 (95% CI, 0.70 to 0.92)
  • 10 trials | 4452 neonates
• There was no significant difference in the composite adverse maternal outcome
  • Crude incidence 22.7%
  • aOR 1.02 (95% CI, 0.89 to 1.18)
  • 10 trials | 4326 women

CONCLUSION:

• For labor induction, balloon catheters were associated with similar cesarean rates compared to vaginal prostaglandins but improved composite perinatal outcomes 
• The authors state

Balloon catheters have been repeatedly proven to be effective in labour induction, are inexpensive, and do not require any specialised preparation or conditions for storage

Learning to insert balloon catheters is possible for a range of clinician skill levels

Balloon catheters have long been used for cervical ripening, and the significant reduction in adverse perinatal outcomes provides the rationale to recommend balloon catheters as the preferred choice 

• In an accompanying expert commentary, the authors
  • Note that different catheters as well as different prostaglandins were combined
  • Cite a recent Cochrane review (see ‘Related ObG Topics’ below) regarding misoprostol’s low rates of fetal and maternal adverse effects and state that low-dose oral misoprostol is ‘probably the optimal method’ for induction

Learn More – Primary Sources:

Balloon catheters versus vaginal prostaglandins for labour induction (CPI Collaborative): an individual participant data meta-analysis of randomised controlled trials

Comment: Induction of labour: first, do no harm

Related ObG Topics: