Preventing bleeding in pregnancy

Postpartum haemorrhage (PPH) is a significant cause of maternal deaths, accounting for around 25% of maternal deaths worldwide (1). A high percentage of the deaths from PPH occur in low- and middle-income countries, a clear demonstration of the unfortunate difference in healthcare infrastructure that we see in the world today. In this blog we discuss what PPH is, the current guidance for managing the condition and whether it could be time to re-evaluate this guidance.

 

What is PPH?

PPH is characterised by significant blood loss at childbirth and associated with serious maternal morbidities including multiorgan failure. It is defined as blood loss of more than 500 mL from the female genital tract after delivery of the foetus (or >1000 mL after a caesarean section) (1).

Why does PPH occur?

During childbirth, a woman’s womb muscles contract in order to limit the bleeding following detachment of the placenta. PPH occurs when these muscles do not contract strongly enough or if the placenta has been left in the womb, resulting in significant blood loss.

Managing PPH – is time to update the guidance?

Naturally healthcare professionals’ preference will be to try and prevent PPH from occurring. Identifying factors that may pre-dispose a woman to PPH, for example placenta praevia or uterine fibroids is key to ensuring that clinicians can plan ahead and make available the necessary resources (1).

When managing PPH, the World Health Organisation (WHO) recommend oxytocin as the first choice, first line treatment (2). However, there are several alternatives. Ergometrine, ergometrine/oxytocin combinations, misoprostol and the newer uterotonic drug carbetocin have all been shown to be efficacious in preventing cases of PPH (3).

With this wide choice of first line treatments available, new research has aimed to answer the question: Do the current recommendations need to be updated?

One recent randomised control trial suggests that a change in guidance could be required. The researchers ask whether in resource-poor countries, oxytocin is the best choice? After all, oxytocin requires special storage conditions to remain stable and effective. This cold chain storage required to transport and store oxytocin may not be available or reliable, causing an increased risk in emergency settings (4). With the majority of cases of PPH occurring in low- and middle-income countries, there may be an need to recommend alternative treatments in a first instance.

Of course, while storage and transportation of a drug is important, efficacy and safety must also be considered. This has been studied in a recent Cochrane review, which suggested that oxytocin in isolation may not be the optimal choice for preventing PPH when compared with alternative treatments (3).

However the debate is not over. At the COGI congress held in London on 23rd-25th November, a special workshop is being held on ‘the prevention and management of bleeding in pregnancy: all about PPH’. Here data from the recent CHAMPION and iMOX clinical trials will be discussed alongside data from the Cochrane review and expert opinions.

We will be there to share with you the very latest in this fascinating discussion, providing a roundup of the key data and conclusions. We hope you are as excited as we are!

 

Sources:

  1. Chandraharan Edwin, Krishna Archana. Diagnosis and management of postpartum haemorrhage. BMJ. 2017; 358:j3875

  2. World Health Organisation. WHO Recommendations for the Prevention and Treatment of Postpartum Haemorrhage. World Health Organization. 2012.

  3. Gallos ID, Williams HM, Price MJ, et al. Uterotonic agents for preventing postpartum haemorrhage: a network meta-analysis. Cochrane Database of Systematic Reviews. 2018; 25(4).

  4. Widmer M, Piaggio G, Nguyen T, et al. Heat-Stable Carbetocin versus Oxytocin to Prevent Hemorrhage after Vaginal Birth. N Engl J Med. 2018; 379(8):743-752