Management of impacted fetal head at Caesarean birth. RCOG scientific impact paper

Contributors

• Katie Cornthwaite
• Rachna Bahl
• Cathy Winter
• Alison Wright
• John Kingdom
• Kate Walker
• Graham Tydeman
• Annette Briley
• Mia Schmidt-Hansen
• Jan van der Scheer
• Tim Draycott

Why it matters

Over a third of women who give birth in the UK have a caesarean birth (CB), and more than one in 20 of these births happen at a late stage in labour when the cervix (neck of the womb) is fully dilated. During caesarean births performed in advanced labour, the baby’s head can become lodged deep in the woman’s pelvis, making delivery difficult. This emergency, called impacted fetal head, is technically challenging for the maternity team and carries serious risks for both mother and baby. People giving birth may experience tears to the uterus (womb), heavy bleeding, or longer recovery. Babies can suffer head or facial injuries, brain oxygen deprivation, nerve damage, and in rare cases, death.

Impacted fetal head is being reported more often, now affecting up to one in 10 unplanned caesareans (1.5% of all births). Two in 100 babies affected die or are seriously injured, and brain injury reports are rising. Teams can use several techniques to deliver the baby, but there is no agreed best approach. This uncertainty can lead to inconsistent care and avoidable harm.

This paper reviews current evidence on predicting, preventing, and managing impacted fetal head, and discusses the implications for future practice. It draws on findings from the Avoiding Brain Injury in Childbirth (ABC) programme, including a systematic review, national survey of professionals, and co-design and pilot testing of a new training package.

What we found

Our systematic review found no clear agreement on the best way to manage impacted fetal head at caesarean birth. Research into different techniques – such as pushing the head up from the vagina (vaginal disimpaction), delivering the baby feet-first (reverse breech extraction), or using the Patwardhan method (a version of the reverse breech extraction, where the baby’s arms are delivered first) suggests that “pull” methods like reverse breech extraction or Patwardhan may lead to fewer complications for mothers than “push” methods.

However, the certainty of this evidence is very low, and outcomes are likely to be influenced by training, skill, and clinical context.

We also found little robust evidence to support the routine use of inflatable balloon devices such as the Fetal Pillow®. While some studies suggest that there could be benefits, concerns about study quality and retracted research mean this procedure should only be done as part of a formal research study, and a research ethics committee needs to approve its use. These findings informed a recent update of NICE guidance on balloon disimpaction.

A national survey highlighted that many maternity professionals feel underprepared to manage IFH, and that they don’t feel very confident in using some of the techniques. To address this, the ABC Collaboration co-designed and piloted – with professionals and representatives of women and birth partners – a new multi-professional training package. The pilot showed high approval ratings of the training and improved participants’ knowledge, skills, and confidence.

Our paper emphasises that high-quality, well-powered trials using agreed definitions and structured documentation are urgently needed to identify the safest and most effective approaches. We identified the lack of a universally accepted definition of impacted fetal head, which gets in the way of research, training, and consistent care. A consensus-based definition – like the one which has recently been identified in a national survey – could help underpin future work. Further research is also needed into language, communication, and shared decision-making with those in labour and their partners.

Even without this new research, practice and outcomes can already improve. The most important areas of change include standardised multi-professional training, clear communication in emergencies, and strong teamwork across professions. These are all priorities in the ABC programme, which the government has announced will be rolled out nationally in 2025.