Summary of findings for the main comparison. Tranexamic acid versus placebo/no treatment for preventing postpartum haemorrhage.
| Tranexamic acid versus placebo/no treatment for preventing postpartum haemorrhage | ||||
| Patient or population: pregnant women undergoing vaginal or caesarean birth who received TA for the prevention of postpartum haemorrhage Settings: Studies were undertaken in China, India, Iran, Pakistan, Turkey Intervention: Tranexamic acid versus placebo/no treatment1 | ||||
| Outcomes | Relative effect or Mean (95% CI) | No of participants (studies) | Quality of the evidence (GRADE) | Comments |
| Blood loss > 400 mL or > 500 mL | RR 0.52 (0.42 to 0.63) | 1398 (6 studies) | ⊕⊕⊕⊝ moderate2 | ‐ 2 studies reported an outcome blood loss greater than 400 mL and 4 trials greater than 500 mL. ‐ 1 study investigated 2 doses of tranexamic acid, e.g. 0.5 g and 1 g and we pooled the data for both groups in this analysis. |
| Blood loss > 1000 mL | RR 0.40 (0.23 to 0.71) | 2093 (6 studies) | ⊕⊕⊕⊝ moderate3 | |
| Mean blood loss (mL) | The mean blood loss in the intervention groups was ‐ 77.79 lower (‐ 97.95 to ‐ 57.64) | 1186 (5 studies) | ⊕⊕⊕⊝ moderate 4 | ‐ 1 study investigated two doses of tranexamic acid, e.g. 0.5 g and 1 g and we pooled the data for both groups in this analysis. ‐ 1 study was opened labelled. |
| Use of additional medical interventions to control PPH | RR 0.48 (0.34 to 0.68) | 2049 (5 studies) | ⊕⊕⊕⊝ moderate5 |
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| Maternal death or severe maternal morbidity such as seizure, thromboembolic events, need for intensive care unit admission, hysterectomy, organ failure | Not estimable | 1511 (4 studies) | ⊕⊕⊝⊝ low6 | |
| Side effects | RR 2.48 (1.36, 4.50) | 2616 (8 studies) | ⊕⊕⊕⊝ moderate7 | |
| Thromboembolic events | RR 0.98 (0.14 to 6.78) | 3012 (11 studies) | ⊕⊕⊝⊝ low6 |
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| CI: Confidence interval; RR: Risk ratio; | ||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||
1 Tranexamic acid was given by IV before caesarean birth or after vaginal birth in doses of 0.5 g or 10 mg/kg and 1 g or 15 mg/kg.
2 Downgraded for risk of bias (‐1). One study had high risk of selection bias; all four studies had unclear risk of performance and detection bias; one study had high risk and another study unclear risk of reporting bias.
3 Downgraded for risk of bias (‐1). One trial used computer‐generated numbers for randomisation, but the groups were unequal, e.g. women in intervention group had BMI > 30, were anaemic and had longer time of surgery and more women in control group had manual removal of placenta and more women in intervention group had placenta removed by controlled cord traction. This trial also had unclear risk of selective reporting bias. All three trials had unclear risk of performance bias and detection bias.
4 Downgraded for risk of bias (‐ 1). One trial had unclear risk and one trial had high risk of selection bias; two trials had unclear risk and two trials had high risk of performance and detection bias; one trial had high risk of attrition bias, and three trials had unclear risk of reporting bias.
5 Downgraded for risk of bias (‐1). Two trials had high risk of allocation concealment and sequence generation bias. Three trials had unclear risk of performance and detection bias.
6 Small sample size to detect this rare outcome (‐1). Also downgraded for ROB (‐1). One trial had high risk and one trial had unclear risk of selection bias; four trials had unclear risk of performance and detection bias; one trial had high risk and another one unclear risk of reporting trials.
7 Downgraded (‐1) for high statistical heterogeneity (I² = 83%).