A randomized controlled trial of Dilapan-S vs Foley balloon for preinduction cervical ripening (DILAFOL trial)

Abstract

The objective of the study was to test the hypothesis that Dilapan-S is not inferior to the Foley balloon for preinduction cervical ripening at term. STUDY DESIGN: Pregnant women !37 weeks scheduled for induction with unfavorable cervix (3 cm dilated and 60% effaced) were randomly assigned to 12 hours of either Foley balloon inflated with 60 mL saline or Dilapan-S for cervical ripening. If the cervix remained unfavorable, then 1 more round of the assigned dilator was used. Management following ripening was left up to the clinical providers. The primary outcome was vaginal delivery. A satisfaction survey was also obtained after the preinduction period. Sample size was based on a noninferiority margin of 10%, 90% power, and an estimated frequency of vaginal delivery of 71% in Foley balloon and 76% in Dilapan-S. RESULTS: From November 2016 through February 2018, 419 women were randomized (209 to Foley balloon; 210 to Dilapan-S). In the intent-totreat analysis, vaginal delivery was more common in Dilapan-S vs Foley balloon (81.3% vs 76.1%), with an absolute difference with respect to the Foley balloon of 5.2% (95% confidence interval, e2.7% to 13.0%) indicating noninferiority for the prespecified margin. The difference was not large enough to show superiority. Noninferiority was confirmed in the per-protocol population (n ¼ 204 in the Foley balloon, n ¼ 188 in Dilapan-S), supporting the robustness of the results. Secondary outcomes were not different between groups, except for a longer time the device remained in place in Dilapan-S compared with the Foley balloon. Maternal and neonatal adverse events were not significantly different between groups. A priori interaction analyses showed no difference in the effect on vaginal delivery by cervical dilation at randomization, parity, or body mass index >30 kg/m 2. Patients with Dilapan-S were more satisfied than patients with the Foley balloon as far as sleep (P ¼ .01), relaxing time (P ¼ .001), and performance of desired daily activities (P ¼ .001). CONCLUSION: Dilapan-S is not inferior to the Foley balloon for preinduction cervical ripening at term. Advantages of Dilapan-S over Foley include Food and Drug Administration approval, safe profile, no protrusion from the introitus, no need to keep under tension, and better patient satisfaction.

Cervical Ripening Efficacy of Synthetic Osmotic Cervical Dilator Compared With Oral Misoprostol at Term

“…These findings are consistent with other recent clinical trials evaluating synthetic osmotic cervical dilators. 14–17…”

Out-of-Hospital Cervical Ripening With a Synthetic Hygroscopic Cervical Dilator May Reduce Hospital Costs and Cesarean Sections in the United States—A Cost-Consequence Analysis

“…It has been suggested that mechanical methods may be most suited to facilitate outpatient cervical ripening (30,35,36). In comparison to the balloon catheter, Saad et al found that the synthetic hygroscopic cervical dilator allowed for a statistically significant increase in the number of women able to perform their daily activities, and their ability to get some relaxation time and sleep (24). After insertion, the single-balloon catheter protrudes from the introitus and is usually kept under tension, while the synthetic hygroscopic cervical dilator remains mostly in the cervical canal, allowing for more freedom of movement (24).…”

“…The potential for outpatient mechanical ripening to reduce cesarean sections adds to the reduction shown for elective IOL at 39 weeks, helping national initiatives to decrease cesareansection rates in the US. Although the synthetic hygroscopic cervical dilator has a higher upfront purchasing cost than some alternatives and may lead to longer times from induction to delivery (22,24), implementing the outpatient strategy may mitigate these factors. In addition, the synthetic hygroscopic cervical dilator is FDA cleared and has been shown to be non-inferior to other ripening agents with the same safety profile as the balloon catheter (non-FDA cleared) and with better patient satisfaction (24), and could thus be suited to the outpatient setting.…”

“…We used outcomes for the balloon catheter or laminaria tent for the synthetic hygroscopic cervical dilator whenever specific outcomes are not available. The synthetic hygroscopic cervical dilator was shown to be non-inferior to the balloon catheter (24). Evidence on the double-balloon catheter is also used for the single-balloon catheter as these were combined in the recent Cochrane review (27).…”

Office-based ambulatory cervical ripening prior to inpatient induction of labor

“…In a randomized trial performed on inpatients, 419 women undergoing CR were assigned to a Foley balloon or Dilapan-S. 16 The vaginal delivery rates were similar in the groups-76% for Foley and 81% for Dilapan-S. Maternal and neonatal adverse effects were similar between the two groups. Compared with Foley catheter, women assigned to Dilapan-S reported greater satisfaction with their CR experience, more sleep, and more ability to perform daily activities.…”