(665) Oxytocin before versus after placenta delivery for postpartum hemorrhage prevention: meta-analysis of randomized controlled trials

Data source: PubMed, Scopus, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials as electronic databases, from the inception of each database to June 2022 with randomized controlled trial (RCT) as publication type for meta-analysis. No restrictions for language or geographic location were applied.

Study eligibility criteria: Selection criteria included RCTs comparing postpartum blood loss when oxytocin is administered before or after delivery of the placenta in patients undergoing vaginal delivery.

Study appraisal and synthesis methods: Primary outcome was postpartum blood loss. Summary measures were reported as relative risk (RR) or as mean difference (MD) with 95% confidence intervals (CI) using random effects. I-squared (Higgins I²) greater than 0% was used to identify heterogeneity.


Results:

Of 3,373 citations, six RCTs met the inclusion criteria, including 2,771 patients undergoing vaginal delivery. 1,388 (50.1%) were randomized to administration of oxytocin before and 1,383 (49.9%) after delivery of the placenta. The timing of oxytocin was not associated with a significant change in mean postpartum blood loss (MD 9.96 ml [-10.12, 30.03]) (Figure 1). Administration of oxytocin before or after delivery of the placenta did not result in a significant difference in the rate of postpartum hemorrhage, change in hemoglobin after delivery, duration of the third stage of labor, rate of retained placenta, need for additional uterotonics, and rate of blood transfusion (Table 1). Subgroup analysis for route of oxytocin administration (IV vs IM) did not show any significant difference for the primary or secondary outcomes.


Conclusion: Timing of oxytocin administration before or after delivery of the placenta does not appear to affect postpartum blood loss or the rate of retained placenta.