1 Choo S-N, et al. BMJ Open 2019;9:e028896. doi:10.1136/bmjopen-2019-028896 Open access MEchanical DIlatation of the Cervix in a Scarred uterus (MEDICS): the study protocol of a randomised controlled trial comparing a single cervical catheter balloon and prostaglandin PGE2 for cervical ripening and labour induction following caesarean delivery Soe-Na Choo, 1 Abhiram Kanneganti, 1 Muhammad Nur Dinie Bin Abdul Aziz, 2 Leta Loh, 1 Carol Hargreaves, 3 Vikneswaran Gopal, 3 Arijit Biswas, 1,2 Yiong Huak Chan, 4 Ida Suzani Ismail, 1 Claudia Chi , 1 Citra Mattar 1,2 To cite: Choo S-N, Kanneganti A, Abdul Aziz MNDB, et al. MEchanical DIlatation of the Cervix in a Scarred uterus (MEDICS): the study protocol of a randomised controlled trial comparing a single cervical catheter balloon and prostaglandin PGE2 for cervical ripening and labour induction following caesarean delivery. BMJ Open 2019;9:e028896. doi:10.1136/ bmjopen-2019-028896 ► Prepublication history for this paper is available online. To view these fles, please visit the journal online (http://dx.doi. org/10.1136/bmjopen-2019- 028896). S-NC and AK contributed equally. Received 06 February 2019 Revised 13 August 2019 Accepted 24 September 2019 For numbered affliations see end of article. Correspondence to Dr Citra Mattar; citramattar@nus.edu.sg Protocol © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ. ABSTRACT Introduction Labour induction in women with a previous caesarean delivery currently uses vaginal prostaglandin E2 (PGE2), which carries the risks of uterine hyperstimulation and scar rupture. We aim to compare the effcacy of mechanical labour induction using a transcervically applied Foley catheter balloon (FCB) with PGE2 in affected women attempting trial of labour after caesarean (TOLAC). Methods and analysis This single-centre non-inferiority prospective, randomised, open, blinded-endpoint study conducted at an academic maternity unit in Singapore will recruit a total of 100 women with one previous uncomplicated caesarean section and no contraindications to vaginal delivery. Eligible consented participants with term singleton pregnancies and unfavourable cervical scores (≤5) requiring labour induction undergo stratifed randomisation based on parity and are assigned either FCB (n=50) or PGE2 (n=50). Treatments are applied for up to 12 hours with serial monitoring of the mother and the fetus and serial assessment for improved cervical scores. If the cervix is still unfavourable, participants are allowed a further 12 hours’ observation for cervical ripening. Active labour is initiated by amniotomy at cervical scores of ≥6. The primary outcome is the rate of change in the cervical score, and secondary outcomes include active labour within 24 hours of induction, vaginal delivery, time-to- delivery interval and uterine hyperstimulation. All analyses will be intention-to-treat. The data generated in this trial may guide a change in practice towards mechanical labour induction if this proves effcient and safer for women attempting TOLAC compared with PGE2, to improve labour management in this high-risk population. Ethics and dissemination Ethical approval is granted by the Domain Specifc Review Board (Domain D) of the National Healthcare Group, Singapore. All adverse events will be reported within 24 hours of notifcation for assessment of causality. Data will be published and will be available for future meta-analyses. Trial registration number NCT03471858; Pre-results. INTRODUCTION The steady increase in caesarean section rates (CSR) and the associated rise in surgical and obstetric morbidity and healthcare costs are of growing concern globally. 1 The 2015 WHO statement on surgical delivery described the optimal CSR as between 10% and 15% by international healthcare consensus. 1 2 However CSR across heterogeneous popula- tions has seen steady inflation from ~20% in the 1990s to ~30% by the 2000s, attributed largely to the rising CSR in nulliparous women in spontaneous labour and women Strengths and limitations of this study ► This is a prospective randomised trial with randomi- sation into one of two interventions. ► This is a prospective randomised open, blinded end- point study, and although participants and proce- duralists applying the priming agent are aware of the intervention, the data analyst is blinded to the intervention. ► This is a direct comparison of two accepted meth- ods of labour induction in women with one previous caesarean section. ► The study has a clear primary endpoint of the rate of change in cervical Bishop score, which is the main determinant of labour success prior to initiating in- duction with amniotomy with or without oxytocin. ► This study is not powered to determine the differ- ences in rates of rare adverse events, including uter- ine scar rupture. on May 6, 2020 by guest. 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