Cervical ripening with self administered iso sorbide mononitrate vaginally, in uncomplicated singleton pregnancies at 39 weeks gestation: a double blind randomised controlled trial

Abstract

Introduction Vaginal iso sorbide mononitrate (ISMN) is effective in pre induction cervical ripening in post dated pregnancies.Objectives To determine the effectiveness and acceptability of ISMN self-administered vaginally at home, in causing cervical ripening in uncomplicated singleton pregnancies at 39 weeks gestation.Methods Consecutive women with uncomplicated singleton pregnancies, presenting between 01 October 2013 and 31 March 2014, with a modified Bishop score (MBS) of < 5 at a gestational age (GA) of 273 days to the University Obstetric Unit of Teaching Hospital Mahamodera Galle, were allocated by stratified (primip/multip) block randomisation to self-administer vaginally at home every other day, five doses of 60 mg of sustained release form of ISMN (ISMN-SR); (n = 72, cases), or pyridoxine 10 mgs (n=72, controls), from GA 273 to 282 days. ResultsThe mean MBS and the mean change of MBS at 282 days, and the proportions with spontaneous onset of labour (SOL) by GA 282 days, were not significantly different between the two groups. A vast majority were satisfied with outpatient therapy (80% cases vs.76% controls), were happy to use it in a subsequent preg-nancy (89% cases vs. 86% controls) and would recom-mend it to a friend (93% cases vs. 90% controls).Conclusions Home adminstrated vaginal ISMN therapy from GA 39 weeks was not effective in causing significant cervical ripening or promoting SOL, but it was acceptable to women.Cervical ripening with self administered iso sorbide mononitrate vaginally, in uncomplicated singleton pregnancies at 39 weeks gestation: a double blind randomised controlled trial This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Pre induction cervical ripening in an outpatient setting

“…Further research is needed to identify the optimum formulation, dose, frequency and duration of therapy, as well as its role as an adjunct intervention to improve the outcome when it is combined with other agents for IOL in post dated pregnancies. However, they may be ineffective prior to 40 weeks gestation 13 . A more robust set of outcome measures, which enable the cervical ripening phase of the induction process to be effectively evaluated, must also be developed 14 .…”

“…(93% in cases vs. 90% in controls). Conclusions: Outpatient vaginal ISMN therapy from 39 weeks' gestation was not effective in causing significant cervical ripening but it was acceptable to women 13 .…”

“…It can cause moderate headaches and clinically insignificant haemodynamic changes in the mother 11 . 4) Outpatient ISMN therapy is acceptable to patients although it is not effective from 39 weeks' gestation 12,13 .…”

Cervical ripening and induction of labour: Inpatient or outpatient, oral misoprostol or Foley catheter?

“…Vaginally administered NO donors, such as isosorbide mononitrate, are effective and can be safely used for outpatient cervical ripening after 40 weeks' gestation in low risk women, although they may be ineffective prior to 40 weeks' gestation [23,32]. As it does not need intensive maternal or fetal monitoring, and is safe and effective for induction of labour if kept in situ for four days, according to currently available evidence, a supra cervical Foley catheter could be considered as an appropriate method for outpatient induction of labour [8,10,12,13].…”