ROTATE: Study Protocol for a Randomised Controlled Trial of Manual Versus Instrumental Rotation of the Fetal Head in Malposition at Birth (Preprint)
Authors: Parris Dawn , Napolitano Raffaele , Bishop Jonathan , Briley Annette , Butler Laura , Cheed Versha , David Anna L , Habib Zaina , Hardy Pollyanna , Hinshaw Kim , Jones Laura L , Lillywhite Rachel , Molloy Eleanor , Nicholls Jacqueline , O'Brien Stephen , Plachcinski Rachel , Shennan Andrew , Simpson Nigel , Treadwell Maureen , Wattar Bassel , Weeks Andrew ,   The ROTATE Study Group, Siassakos Dimitrios 
Published: February 2025

UNSTRUCTURED

Background

Approximately 5% of women will be affected by fetal malposition at full cervical dilatation, with the occiput in transverse or posterior positions. These women are more likely to require assistance to give birth to their babies with either rotational vaginal birth or caesarean birth at full dilatation. Three different rotational methods can be used: rotational (Kielland’s) forceps, rotational vacuum, and manual rotation. Current evidence supporting the use of the three rotational methods is only from observational data. To date, no randomised controlled trial of rotational methods has been completed.

Methods and analysis

ROTATE is a pragmatic, multi-centre, two-arm parallel group, open-label randomised controlled trial of manual versus instrumental rotation of the fetal head in malposition at birth with an internal pilot and an embedded qualitative process evaluation. The primary outcome is to evaluate whether manual versus instrumental rotation at full cervical dilatation reduces the risk of severe perineal trauma (superiority outcome), defined as a third or fourth degree tear, without substantially increasing the risk of caesarean birth at full dilatation (non-inferiority co-primary outcome).

A sample size calculation found that 4988 participants are required to detect a clinically meaningful reduction of third- or fourth-degree tears from 6% to 4% with 90% power (alpha 0.05). A total sample size of 5200 participants from approximately 40 sites is anticipated, as loss to follow-up is expected to be about 4%. Neonatal trauma, a composite of potential outcomes relating to intrapartum hypoxia and physical trauma, is a safety signal. The setting is NHS consultant-led maternity units across the UK.

Randomisation is performed after eligibility has been confirmed and verbal consent has been obtained. Randomisation is undertaken via a 24-hour telephone service or online system. Participants are randomised at an individual level on a 1:1 ratio to manual or instrumental (forceps/vacuum) rotation. Written consent is sought postnatally.

Ethics and dissemination

Ethical approval was granted from London – Surrey Research Ethics Committee, REC reference 22/LO/0157 from 19th May 2022.
There are plans for dissemination of the vital findings of this study in peer-reviewed journals, international conferences and into national courses on assisted vaginal birth in the UK including ROBuST (RCOG Operative Birth Simulation Training).

Trial Registration and Status

ROTATE protocol version 5.0, dated 15/12/2023. The pilot opened and the first participants was recruited in September 2022. The trial closes on 3rd February 2025.

Trial registration does not collect items from the World Health Organization Trial Registration Data Set