BACKGROUND AND PURPOSE:

• Mechanical cervical ripening may improve time to delivery following prelabor rupture of membranes (PROM) but there may be risk of infection
• Mackeen et al. (Obstetrics & Gynecology, 2018) compared the use of a transcervical Foley catheter plus oxytocin infusion versus oxytocin infusion alone for labor induction and cervical ripening

METHODS:

• Randomized, multicenter controlled trial
• Participants: Women with a live, singleton gestation ≥34 weeks with
  • PROM
  • Unfavorable cervical examination (≤2 cm or ≤80% effaced)
  • No contraindication to labor
    • In the absence of ≥1 cm cervical dilation after 2 hours, patients with contractions could be included in the study
  • Participants were randomized as follows
    • Transcervical Foley catheter inflated to 30 cc with concurrent oxytocin infusion
      • Placed/taped under tension
    • Oxytocin infusion alone
  • Initial oxytocin was 2 milliunits/min and increased by 2 milliunits/min every 30 minutes to achieve an adequate contraction pattern
    • Maximum dose of 30 milliunits/min
  • Chorioamnionitis defined as temperature ≥38°C (or 100.4°F) and ≥2 or more of the following
    • Uterine tenderness | Maternal tachycardia ≥100 BPM | Fetal tachycardia ≥160 BPM | Foul smelling amniotic fluid | Maternal leukocytosis > 15,000 cells/mL
  • Antibiotics
    • Group B streptococci prophylaxis or clinically suspected intraamniotic infection as indicated
  • Primary study outcome
    • Interval from induction to delivery
  • Secondary outcomes
    • Mode of delivery
    • Maternal and newborn outcomes

RESULTS:

• 201 women were enrolled in the study
  • 93 were allocated to Foley group
  • 108 to oxytocin group
• Time to delivery was not significantly different between groups (P=.69)
  • Foley group: 13.9 hours (±6.9 SD)
  • Oxytocin group: 14.4 hours (±7.9 SD)
• There were more cases of clinical chorioamnionitis (8% compared with 0%, P<.01) in the Foley group compared with the oxytocin group

CONCLUSION:

• The introduction of Foley in addition to oxytocin did not shorten time between induction and delivery but did introduce risk for chorioamnionitis
• Limitations
  • Study used clinical assessment of infection and not placental pathology (1/3 of case underwent pathologic review)
• However, authors state that the study was adequately powered to determine a difference in chorioamnionitis and the results of this study “should make us question whether use of a Foley catheter is appropriate in those with ruptured membranes”

Learn More – Primary Sources:

Foley Plus Oxytocin Compared With Oxytocin for Induction After Membrane Rupture: A Randomized Controlled Trial.

Related ObG Topics:

Foley vs Misoprotol:  What is the Most Cost-Effective Way to Induce Labor?

The FIAT-M study: Simultaneous or Sequential Foley and Oxytocin for Induction in Multiparous Women

Does Stopping Oxytocin in Active Phase of Labor Alter Cesarean Section Rates?