Mike: Hello, I’m Mike Clarke, podcast editor for the Cochrane Library. Globally, postpartum haemorrhage is responsible for a quarter of maternal deaths after childbirth. Tears of the perineum, which are common in vaginal births, are a major contributor to this excessive blood loss, and a variety of techniques are used to try to prevent them. The effects of these interventions are reviewed in a new Cochrane Review published in October 2024 and two of the authors, Tilly Fox and Kerry Dwan from The Liverpool School of Tropical Medicine in the UK, talk about the findings in this podcast.

Tilly: Hello Kerry, first of all, could you tell us a little about the perineal techniques. What are they and what do they do?

Kerry: Perineal techniques are preventative strategies which can be used during the second stage of labour to prevent or reduce trauma to the woman’s perineum. They include perineal management such as ‘hands off/hands poised’, perineal massage, vocalisation and application of warm compresses.

Tilly: So why is it important to have up-to-date information on the effectiveness of these techniques during the second stage of labour?

Kerry: Firstly, maternal mortality remains unacceptably high, far above the United Nations’ Sustainable Development Goal 3.1. To reinvigorate efforts to achieve this goal, the World Health Organisation convened a Global Summit on postpartum haemorrhage in March 2023. This led to a Roadmap to combat postpartum haemorrhage in the run-up to 2030, which is the target date for the Sustainable Development Goals. A central component is the development of a consolidated postpartum haemorrhage guideline, bringing together key guideline developers, including the World Health Organisation, the International Federation of Gynecology and Obstetrics and the International Confederation of Midwives. The aim is to jointly publish a single, up-to-date repository for all global recommendations on postpartum haemorrhage prevention, diagnosis and treatment. This harmonized and innovative approach should address inconsistencies across guidelines and minimise duplication of efforts. This should ensure that recommendations are comprehensive, reliable and consistent, which, in turn, should promote uptake of the recommendations in clinical practice, especially in high-burden countries.

Tilly: And how did that lead to this Cochrane Review?

Kerry: The World Health Organisation Technical Advisory Group for Maternal and Perinatal Health Guidelines and the postpartum haemorrhage Consolidated Guideline Steering Group highlighted the need for a series of new evidence syntheses to inform the recommendations. This included the one we took on, on techniques to avoid perineal trauma. This required a careful examination of the evidence on the critical outcomes of second, third and fourth degree tears and postpartum haemorrhage greater than 500 millilitres. We had also hoped to look at adverse effects but none of the identified studies reported on these.

Tilly: So, how much research was available and what does it say about the effects of perineal techniques during the second stage of labour on perineal trauma and postpartum complications?

Kerry: We identified a total of 17 clinical trials involving nearly 13,700 women in active labour, who received one of the perineal techniques or usual care. The trials showed a lack of certainty or little to no difference for hands off versus hands on, vocalisation, massage and the combination of warm compress and massage. However, putting a warm compress on the perineum is likely to reduce third or fourth degree tears and to provide a large reduction in perineal pain, compared to usual care or no warm compress.

Tilly: Overall, what’s the take-home message about using perineal techniques during the second stage of labour?

Kerry: Unfortunately, it’s that current evidence on the effects of perineal techniques to prevent post birth injury and blood loss is very uncertain. This is because of poor study quality and small trials. What is needed are large, well conducted trials that measure postpartum haemorrhage, adverse effects and maternal satisfaction.

Tilly: Thanks Kerry. If people would like to read the full review, which includes information on some techniques that we’ve not mentioned in this podcast, how can they get hold of it?

Kerry: Thanks Tilly. It’s available at Cochrane Library dot com. If people go to the website and type “perineal techniques” into the search box, they’ll see a link to it.