Cervical ripening with the Foley catheter

Recent advances in the induction of labor

The rate of labor induction is steadily increasing and, in industrialized countries, approximately one out of four pregnant women has their labor induced. Induction of labor should be considered when the benefits of prompt vaginal delivery outweigh the maternal and/or fetal risks of waiting for the spontaneous onset of labor. However, this procedure is not free of risks, which include an increase in operative vaginal or caesarean delivery and excessive uterine activity with risk of fetal heart rate abnormalities. A search for "Induction of Labor" retrieves more than 18,000 citations from 1844 to the present day. The aim of this review is to summarize the controversies concerning the indications, the methods, and the tools for evaluating the success of the procedure, with an emphasis on the scientific evidence behind each.

Single versus double-balloon catheters for the induction of labor of singleton pregnancies: a meta-analysis of randomized and quasi-randomized controlled trials

OBJECTIVE

To compare the efficacy of single- versus double-balloon catheter (SBC vs. DBC) for cervical ripening and labor induction with an unfavorable cervix.

METHODS

Systematic review and meta-analysis of randomized controlled trials (RCTs) or quasi-RCTs (qRCT) regarding the use of SBC or DBC for labor induction of live singleton cephalic pregnancies (≥ 35 weeks) of any parity with an unripe cervix (Bishop score ≤ 6). Nine research databases were searched for original articles published in all languages up to November 2017 comparing both devices for labor induction. Five RCTs and one qRCT were included. Primary outcome measures were time from intervention (device placement) to birth time, vaginal delivery and cesarean section rates, and maternal satisfaction with the procedure. Risk of bias was evaluated with the Cochrane tool. Random effects models were used to combine data for meta-analyses. Summary measures were reported as mean differences and risk ratios (RR) with 95% confidence intervals.

RESULTS

Regardless of parity, pooled analyses of the six trials (n = 1060 women) found that mean intervention to birth time, vaginal delivery and cesarean section rates, and maternal satisfaction to the procedure were similar for both studied groups (SBC vs. DBC).

CONCLUSION

Measured primary outcome measures were similar regardless of the type of device used for labor induction of singleton pregnancies.

[Double-balloon device and intravaginal dinoprostone for cervical ripening in women with unfavourable cervix]

OBJECTIVES

To compare the efficiency of a double cervical ripening (mechanical agent and dinoprostone) to a dinoprostone-only ripening in women with an unfavourable cervix.

METHODS

In a retrospective study from January 2008 to October 2013, 96 patients were included with the following criteria: pregnancies over 37 weeks, singleton, vertex presentation, medical indication for induction of labor, no premature rupture of membranes and very unfavourable cervix (Bishop score ≤ 3). Patients were classified into 2 groups: intravaginal dinoprostone for 24h (prostaglandin group, n=38) and double-balloon device for 12h followed by intravaginal dinoprostone for 24h (balloon+prostaglandin group, n=58).

RESULTS

There was no difference in vaginal delivery rates between the 2 groups (balloon+prostaglandin group 51.7%, prostaglandin group 50%, P=0.87). The Bishop score after cervical ripening was significantly higher in the balloon+prostaglandin group (4.4 versus 2.4, P<0.0001), but the interval between the induction and the delivery was longer (33.6h versus 24.9h, P=0.0044). There was no significant difference for maternal and neonatal complications.

CONCLUSION

A double cervical ripening (with mechanical agent and dinoprostone) allows the Bishop score to be improved without increasing the rate of vaginal delivery, for patients with a Bishop score ≤ 3.

[Cervical ripening: is there an advantage for a double-balloon device in labor induction?]

OBJECTIVES

To compare efficiency of a double-balloon to vaginal prostaglandins for cervical ripening in patients with unfavourable cervix.

PATIENTS AND METHODS

Fifty patients induced with a double-balloon were compared to 50 patients receiving vaginal prostaglandins. Matching criteria were age, parity, history of uterine scar, gestational age and Bishop score. The primary outcome was failure induction. Secondary outcomes included improvement in Bishop score, ripening-to-delivery interval, caesarean section rate, maternal and neonatal morbidity.

RESULTS

Risk of failed induction (16% in the double-balloon group vs. 14% in the prostaglandins group) and caesarean section rate (28% vs. 36%) were similar in the two groups. The proportion of favourable cervix and the time to obtain a better Bishop score were similar with the two methods. Maximal pain score during cervical ripening was significantly lower in the double-balloon group (P<0.001). Ripening-to-delivery interval (30.4 h ± 15.6h vs. 28.9 h ± 20.5h) was not different between the two groups. There was no difference about maternal and neonatal outcomes.

DISCUSSION AND CONCLUSION

The double-balloon was as efficient as vaginal prostaglandins. The ripening-to-delivery interval was not different between the two groups. The main advantage of this device could be a better tolerance favourishing patient satisfaction.

Foley Catheter vs Prostaglandin as Ripening Agent in Pregnant Women With Premature Rupture of Membranes

Context: Although studies support the efficacy of the Foley catheter (FC) as a cervical ripening agent in pregnant women at term with intact membranes, its efficacy has not been well studied in women with premature rupture of membranes (PROM).

Objective: To compare the interval to delivery in women with PROM who underwent induction of labor and cervical ripening with mechanical (FC) vs nonmechanical (prostaglandin [PG]) cervical ripening agents.

Design: Retrospective medical record review at 2 hospitals of pregnant women who delivered between January 2009 and April 2011.

Setting: Thomas Jefferson University Hospital in Philadelphia, Pennsylvania, and Christiana Care Health System in Newark, Delaware.

Patients: Pregnant women with singleton gestations 36 weeks or greater who presented with PROM.

Interventions: Cervical ripening with FC or PG.

Main Outcome Measures: The primary outcome was time from induction until delivery. Secondary outcomes included epidural use, maximum temperature during labor, number of vaginal examinations, occurrence of tachysystole, oxytocin dose, delivery mode, chorioamnionitis, and neonatal Apgar score.

Results: Of 155 medical records of patients who met the inclusion criteria, 33 women underwent cervical ripening with PG (ie, misoprostol) and 122 with FC. The interval to delivery was almost halved in women who underwent cervical ripening with FC compared with misoprostol (736 vs 1354 minutes; P<.01). Compared with the women in the misoprostol group, those in the FC group received a statistically significant higher dose of oxytocin (P<.01). There were no statistically significant differences between the groups with respect to the remaining secondary outcomes. Of note, all of the women who received FC were from Christiana Care Health System, and all women who received misoprostol were from Thomas Jefferson University Hospital.

Conclusion: Foley catheters may help shorten the interval to delivery in women who are candidates for cervical ripening after PROM at or near term. There does not appear to be an increased risk for cesarean delivery or chorioamnionitis in those treated with FC.

Is transcervical Foley catheter actually slower than prostaglandins in ripening the cervix? A randomized study

OBJECTIVE

The purpose of this study was to determine whether the maximum time for cervical ripening (from 24-12 hours) would influence the efficacy of a transcervical Foley catheter and to compare efficacy to that of a prostaglandin E(2) vaginal insert.

STUDY DESIGN

Three hundred ninety-seven women were assigned randomly to (1) Foley catheter left in place for a maximum of 24 hours, (2) Foley catheter left in place for a maximum of 12 hours, or (3) prostaglandin E(2) controlled-release vaginal insert. Primary outcome was vaginal delivery within 24 hours.

RESULTS

There were no differences in vaginal delivery rates. The proportion of women who achieved vaginal delivery in 24 hours was lower in the 24-hour Foley catheter group than in the other 2 groups (24-hour Foley catheter, 21.0%; 12-hour Foley catheter, 59.8%; vaginal prostaglandin E(2), 48.5%; P < .0001).

CONCLUSION

Cutting the ripening time with a Foley catheter by one-half increases the proportion of women who deliver vaginally within 24 hours and yields efficacy similar to that of prostaglandin E(2) vaginal insert.