Postpartum haemorrhage (PPH) rates in randomized trials of PPH prophylactic interventions and the effect of underlying participant PPH risk: a meta-analysis

Abstract

Background: Postpartum haemorrhage (PPH) remains a leading cause of maternal mortality. Many trials assessing interventions to prevent PPH base their data on low risk women. It is important to consider the impact data collection methods may have on these results. This review aims to assess trials of PPH prophylaxis by grading trials according to the degree of risk status of the population enrolled in these trials and identify differences in the PPH rates of low risk and high risk populations. Methods: Systematic review and meta-analysis using a random-effects model. Trials were identified through CENTRAL. Trials were assessed for eligibility then graded according to antenatal risk factors and method of birth into five grades. The main outcomes were overall trial rate of minor PPH (blood loss ≥500 ml) and major PPH (> 1000 ml) and method of determining blood loss (estimated/measured).

Carbetocin versus Oxytocin: A Comparative Study to Prevent Postpartum Hemorrhage in Pre-eclamptic Women Delivered by Caesarean Section

“…It is classified as: Minor PPH (blood loss 500-1000 ml) and major PPH (more than 1000 ml). Almost 500,000 women die due to this preventable cause each year, especially hemorrhage that occurred at time of delivery (4) . Other nonfatal complications may occur as Sheehan's syndrome (Pituitary infarction), coagulopathy, and organ damage due to hypotension, shock, and risk of hysterectomy (5) .…”

Intramuscular oxytocin versus Syntometrine® versus carbetocin for prevention of primary postpartum haemorrhage after vaginal birth: a randomised double‐blinded clinical trial of effectiveness, side effects and quality of life

“…Further to this, the rate of instrumental vaginal births in our study was ~21–24%, compared with ~4% in CHAMPION. Instrumental vaginal birth is an important risk factor for PPH, 23 and complex births may be under‐represented in trials used to estimate PPH incidence 24 …”

“…Instrumental vaginal birth is an important risk factor for PPH, 23 and complex births may be underrepresented in trials used to estimate PPH incidence. 24 There is insufficient evidence to support one method of blood loss estimation over another, 25 including acceptability to women. We made efforts to exclude liquor and combined volumetric and gravimetric measurement of blood loss by using direct collection of blood along with weighing blood-soaked swabs and linen, excluding dry weights.…”

Pregnancy Outcome at Primary Healthcare Centers With Basic Emergency Neonatal Obstetric Services During Covid-19 Pandemic

“…According to Evensen, Anderson, & Fontaine (2017), postpartum hemorrhage can occur in patients without risk factors for hemorrhage, and around 20% of PPH occurs in women with no risk factors. A study reviewed by Hawker & Weeks (2020), also showed that antenatal risk factors might not significantly contribute to the PPH rates while the method of birth could have more impact. It means that mothers can develop obstetric complications even with no risk factors.…”