BACKGROUND:Active management of the third stage of labour involves giving a prophylactic uterotonic, early cord clamping and controlled cord traction to deliver the placenta. With expectant management, signs of placental separation are awaited and the placenta is delivered spontaneously. Active management was introduced to try to reduce haemorrhage, a major contributor to maternal mortality in low-income countries. OBJECTIVES:To compare the effectiveness of active versus expectant management of the third stage of labour. SEARCH STRATEGY:We searched the Cochrane Pregnancy and Childbirth Group Trials Register (May 2010). SELECTION CRITERIA:Randomised and quasi-randomised controlled trials comparing active versus expectant management of the third stage of labour. DATA COLLECTION AND ANALYSIS:Two authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. MAIN RESULTS:We included five studies (6486 women), all undertaken in hospitals in high-income countries. Four compared active versus expectant management, and one compared active versus a mixture of managements. Analysis used random-effects because of clinical heterogeneity. Active management reduced the average risk of maternal primary haemorrhage (more than 1000 ml) (risk ratio (RR) 0.34, 95% confidence interval (CI) 0.14 to 0.87, three studies, 4636 women) and of maternal haemoglobin less than 9 g/dl following birth (RR 0.50, 95% CI 0.30 to 0.83, two studies, 1572 women) for women irrespective of their risk of bleeding. We identified no difference in Apgar scores less than seven at five minutes. Active management showed significant increases in maternal diastolic blood pressure, after-pains, use of analgesia and more women returning to hospital with bleeding. There was also a decrease in the baby's birthweight with active management, reflecting the lower blood volume from interference with placental transfusion. There were similar findings for women at low risk of bleeding except there was no significant difference identified for severe haemorrhage. Hypertension and interference with placental transfusion might be avoided by using modifications to the active management package, e.g. omitting ergot and deferring cord clamping, but we have no direct evidence of this here. AUTHORS' CONCLUSIONS:Active management of third stage reduced the risk of haemorrhage greater than 1000 ml in an unselected population, but adverse effects are identified. Women should be given information on the benefits and harms to support informed choice. Given the concerns about early cord clamping and the potential adverse effects of some uterotonics, it is critical now to look at the individual components of third stage management. Data are also required from low-income countries.