In normal birth there should be a valid reason to interfere with normal processes. Yet, active management of third stage labor is being imposed on women who have no known risks of postpartum hemorrhage. This article examines the evidence from existing randomised trials comparing active and physiological third stage care for its relevance and validity to the effectiveness of physiological third stage care for women who are at low risk of postpartum hemorrhage. Consideration is given to midwifery and medical perspectives of the following definitions: ‘postpartum hemorrhage’; ‘low-risk status’; ‘active’; ‘expectant’ and ‘physiological’ third stage care. A systematic search of the research literature regarding the third stage of labour is described. Four randomised trials and a meta-analysis by Cochrane were considered. These studies are examined in terms of their potential generalisability to women who are at low risk of postpartum hemorrhage. All trials included women who were at high risk of postpartum hemorrhage. The existing research does not provide relevant and valid evidence about the effectiveness of physiological third stage care, as defined by midwives, for women who are at low risk of postpartum hemorrhage.