Synthetic Osmotic Dilators for Pre-Induction Cervical Ripening – an Evidence-Based Review

Abstract

Mechanical methods have gained growing interest for pre-induction cervical ripening in women with an unripe cervix, since they have a better safety profile compared to prostaglandins. Balloon catheters have been the gold standard method for decades, while there was a lack of data on synthetic osmotic cervical dilators.

Not until 2015, when Dilapan-S was approved by the Food and Drug Administration (FDA) for induction of labor, numerous studies have been published on the use of Dilapan-S in this field. The rate of vaginal deliveries associated with the use of Dilapan-S ranges from 61.6 to 81.7%, and no serious complications needing further interventions have been reported to this date.

Dilapan-S was shown to be as effective as the Foley balloon catheter as well as the 10 mg PGE₂ vaginal insert and orally applied misoprostol (25 µg every 2 hours) in achieving vaginal delivery, but patient’s satisfaction during the cervical ripening process was significantly higher compared to the other methods and the rate of uterine hyperstimulation was significantly lower compared to prostaglandins (PGs).

Minor complications (e.g. vaginal bleeding) associated with the use of Dilapan-S were < 2%, and maternal infectious morbidity was not higher compared to Foley balloon and vaginal PGE₂ or misoprostol.

Due to these beneficial properties Dilapan-S might be an ideal option for outpatient cervical ripening, as shown in a recent randomized clinical trial comparing inpatient to outpatient cervical ripening.

Furthermore, according to the manufacturers’ product information, Dilapan-S is the only cervical ripening method that is not contraindicated for induction of labor in women with a previous cesarean section. Upcoming guidelines should consider synthetic osmotic cervical dilators as an effective and safe method for cervical ripening/induction of labor acknowledging that more evidence-based data are mandatory, particularly in patients with a previous cesarean section.

Zusammenfassung

Mechanische Methoden haben zur Zervixreifung/Geburtseinleitung bei Schwangeren mit unreifer Zervix zunehmendes Interesse erlangt, da diese ein höheres Sicherheitsprofil aufweisen als Prostaglandine. Ballonkatheter sind seit Jahrzehnten der Goldstandard, während es bisher nur wenige Daten zu synthetischen osmotischen Zervixdilatatoren gibt.

Erst als Dilapan-S 2015 von der Food and Drug Administration (FDA) zur Geburtseinleitung zugelassen wurde, wurden zahlreiche Studien zum Einsatz von Dilapan-S veröffentlicht. Die Rate vaginaler Entbindungen im Zusammenhang mit der Anwendung von Dilapan-S liegt zwischen 61,5 und 81,7%, wobei bis heute über keine schwerwiegenden Komplikationen mit Notwendigkeit zu weiteren Interventionen berichtet wurde.

Dilapan-S erwies sich bezüglich der Rate vaginaler Geburten als vergleichbar effektiv wie der Foley-Ballonkatheter, das 10-mg-Prostaglandin-E₂-(PGE₂-)Vaginalinsert und Misoprostol oral (25 µg alle 2 Stunden). Allerdings zeigte sich eine wesentlich höhere Patientinnenzufriedenheit während des Zervixreifungsprozesses im Vergleich zu den anderen Methoden, und darüber hinaus war die Rate an uterinen Hyperstimulationen signifikant geringer im Vergleich zu Prostaglandinen.

Die Rate leichter Komplikationen (z. B. vaginale Blutung) im Zusammenhang mit der Anwendung von Dilapan-S liegt < 2%, und die infektionsbedingte maternale Morbidität war im Vergleich zum Foley-Ballonkatheter, zu vaginalem PGE₂ und Misoprostol nicht höher.

Aufgrund dieser vorteilhaften Eigenschaften könnte Dilapan-S eine ideale Option für die ambulante Zervixreifung darstellen, wie erst kürzlich in einer randomisierten klinischen Studie gezeigt werden konnte, in welcher die stationäre mit der ambulanten Zervixreifung verglichen wurde.

Darüber hinaus ist Dilapan-S, laut Produktinformation des Herstellers, die einzige Methode zur Zervixreifung, die im Rahmen der Geburtseinleitung bei Schwangeren mit vorangegangenem Kaiserschnitt nicht kontraindiziert ist. Zukünftige Leitlinien sollten daher synthetische osmotische Zervixdilatatoren als eine wirksame und sichere Methode zur Zervixreifung/Geburtseinleitung berücksichtigen, allerdings sind mehr evidenzbasierte Daten zwingend erforderlich, insbesondere bei Patientinnen mit vorangegangenem Kaiserschnitt.

Keywords

synthetic osmotic dilator (Dilapan-S) - pre-induction cervical ripening - efficacy - safety - balloon catheter - prostaglandins

Schlüsselwörter

synthetische osmotische Dilatatoren (Dilapan-S) - Zervixreifung/Geburtseinleitung - Effektivität - Sicherheitsprofil - Ballonkatheter - Prostaglandine

Publication History

Received: 23 March 2023

Accepted: 31 May 2023

Article published online:
07 July 2023

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