Prophylactic tranexamic acid for reducing blood loss in pregnant females undergoing cesarean section: A systematic review and meta-analysis

ObjectiveWe aim to assess the efficacy of prophylactic tranexamic acid (TXA) in reducing blood loss after cesarean section (CS). MethodsWe systematically searched PubMed and Embase for randomized controlled trials published between 1990 and 2023 to conduct a meta-analysis on adult women undergoing CS and receiving prophylactic TXA. ResultsTwenty-four trials, comprising 19 584 participants, were included. Most studies included women with healthy, full-term, singleton pregnancies. The pooled estimate showed a reduction in mean blood loss in the TXA arm with a standardized mean difference (SMD) of -1.50 (-2.03, -0.98: p < 0.001). There was a high level of heterogeneity (I-2 98.86%). A subgroup analysis demonstrated no statistical difference in the effect of TXA on blood loss at 2 h of follow-up with SMD of -2.24 (-3.23, -1.35) compared to -1.07 (-1.56, -0.58) and -1.10 (-2.62, -0.42) at 24 and 48 h, respectively (p = 0.11). The effect of TXA on blood loss was smaller in high-income countries with SMD -0.24 (-0.44, -0.04) (I-2 63%) than in low-/middle-income countries -1.78 (-2.35, -1.21) with I2 98%. Only three studies had low risk of bias and the effect of TXA from two of them was SMD -0.31 (-0.54, -0.09) (I-2 0%). ConclusionsDespite the apparent beneficial effect of TXA in reducing blood loss after CS for women with uncomplicated term pregnancies, heterogeneity remains a serious concern. The current body of knowledge consists predominantly of small, likely biased studies, and large unbiased studies show only limited effects of prophylactic TXA.