Synthetic osmotic dilators in the induction of labour-An international multicentre observational study.

INTRODUCTION: To evaluate the effects of synthetic osmotic dilators (Dilapan-S/ Dilasoft) in women who required induction of labour in a large prospective multicentre international observational study. MATERIALS AND METHODS: Primary outcomes were duration of Dilapan-S/Dilasoft insertion (hours), total induction - delivery interval (hours) and the rate of vaginal deliveries within 24 h (%). Secondary outcomes were the number of dilators inserted, Bishop score increase after extraction of Dilapan-S/Dilasoft, complications during induction (uterine contractions, uterine tachysystole and hyperstimulation, effect on the fetus) and post induction (infections and neonatal outcomes), agents / procedures used for subsequent induction of labour, immediate rate of spontaneous labours following cervical ripening period, rate of spontaneous vaginal deliveries, rate of instrumental vaginal deliveries and caesarean sections. RESULTS: Total of 543 women were recruited across 11 study sites, of which, 444 women were eligible for analysis. With Dilapan-S/Dilasoft use of <12 h (n = 188) the overall vaginal delivery rate was 76.6% with 45.7% of these births occurring within 24 h, 66% within 36 h and 75.5% within 48 h from insertion of Dilapan-S/Dilasoft. The mean insertion-delivery interval for this group was 24.3(±10.4) hours. With Dilapan-S/Dilasoft use of >12 h (n = 256), the overall vaginal delivery rate was 64.8%, with 16% of these births occurring within 24 h, 48.4% within 36 h and 54.7% within 48 h from insertion of Dilapan-S/Dilasoft. The mean insertion-delivery interval for this group was 39.1(±29.2) hours. The mean gain in the Bishops score was +3.6(±2.3). The mean number of Dilapan-S/Dilasoft dilators used was 3.8 (±1.1). The overall rate of caesarean section was 30.1%. The overall complication rate was low including infection risk. No adverse neonatal outcome was attributable to the use of Dilapan-S/Dilasoft. CONCLUSION: Dilapan-S/Dilasoft are safe and effective methods for cervical ripening. Their use is associated with low maternal and neonatal complication rates. Future research should aim at level I clinical trials comparing Dilapan-S to other mechanical or pharmacological cervical ripening agents. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02318173.

Synthetic osmotic dilators for cervical preparation prior to abortion-An international multicentre observational study.

OBJECTIVES: To evaluate the outcomes with the use of Dilapan-S for cervical preparation prior to medical or surgical abortion. STUDY DESIGN: International, multicentre, prospective observational study in women between 6 + 0-24 + 0 weeks' gestation. The study was conducted across 7 study sites in 4 countries, between 1/5/2015 to 31/12/2016. The primary outcomes studied were the number of dilators used and the duration required for cervical preparation prior to abortion. Secondary outcomes were complications of dilator use and infection. Participants were followed-up for 4 weeks post procedure to capture any delayed complications. RESULTS: A total of 483 women were enrolled with 439 women eligible for analysis. Medical abortion was performed in 38% (n = 165) women and surgical abortion in 62% (n = 274). For medical abortions and surgical abortions, an average of 3 osmotic dilators for time interval of 4-7 hours provided effective cervical preparation. Medical abortions were performed as day-case procedures (<12 h) in 81% of women. There was no difference in using either adjunctive misoprostol or Dilapan-S followed by misoprostol for cervical ripening effect to achieve complete medical abortion. Dilapan-S permitted surgical abortions to be performed as same-day procedures (<12 h), in 85% of women regardless of gestational age and without the need to use adjunctive or additional misoprostol. There were no serious adverse events reported with the use of Dilapan-S, including in women with a previous caesarean section. The overall infectious morbidity was 0.9% of cases with no causal relationship with the use of synthetic osmotic dilator use (for a length <24 h). In addition, Dilapan-S was reported as easy to insert and remove in over 90% of women. CONCLUSION: Dilapan-S is a safe and effective method for cervical preparation for medical and surgical abortions up to 24 weeks' gestation. It allows medical and surgical abortions to be performed as day case procedures and is associated with a low complication rate. Future research should aim at directly comparing Dilapan-S and preferred pharmacological agents in a randomised controlled trial.

Experimental comparison of properties of natural and synthetic osmotic dilators.

PURPOSE: The in vitro study compares natural and synthetic osmotic dilators in selected parameters influencing their clinical efficacy. METHODS: Diameters of Laminaria and synthetic dilators (Dilapan-S and Dilasoft) were measured in dry state, during free swelling in isotonic solution and during swelling against a force. Three aspects were evaluated-diameter increase, speed of action and consistency of action. RESULTS: The maximum diameter increase of 3 and 4-mm Dilapan-S was 3.6 and 3.3 times, of Dilasoft 3.2 and 3.1 times, respectively. For Laminaria, it was 2.9 and 2.7 times. The difference between synthetic dilators and Laminaria was statistically significant (p < 0.01). Synthetic dilators also swelled faster. Under applied counter force, synthetic dilators increased their diameter more than Laminaria (+3.6 mm for Dilapan-S, +3.8 mm for Dilasoft, +1.2 mm for Laminaria; p < 0.01) and achieved faster expansion. Synthetic dilators also showed significantly higher consistency between samples in all experiments. CONCLUSIONS: Synthetic dilators compared to Laminaria reached higher maximum diameters, acted faster, were more consistent and were able to expand against force three times more. The results support clinical observations that synthetic dilators are more suitable and preferable for same-day D&E procedure and that fewer synthetic dilators are needed to achieve the same effect.