Date	Event	Description
31 October 2016	New search has been performed	Search updated and four new trials incorporated (Akbarzadeh 2014; Hans 2013; Isbir 2015; Safarzadeh 2012). A 'Summary of findings' table has been added for this update. Six new outcomes have been added.
31 October 2016	New citation required but conclusions have not changed	Four new trials included, but conclusions remain unchanged.
29 June 2013	New citation required but conclusions have not changed	Review updated. No new trials or data included.
29 June 2013	New search has been performed	Search updated. One new abstract identified and added to Characteristics of studies awaiting classification because it does not contain sufficient details to permit classification (Safarzadeh 2013).
12 July 2012	New citation required but conclusions have not changed	One new trial added (Yuenyong 2012). Data inadvertently omitted for one outcome (postpartum depression) from a prior trial (Hofmeyr 1991) have now been included. Minor clarifications to the text and changes to Results which did not substantively alter Conclusions.
14 June 2012	New search has been performed	Search updated and one new trial met inclusion criteria. One other trial report and seven new abstracts were found, one of which describes an ongoing study, and none of which contain sufficient details to permit classification.
31 December 2010	New search has been performed	Search updated. We evaluated and added new trials. We obtained additional information from trial authors. Other revisions included numerous changes to bring the entire Review up‐to‐date in terms of current methodological guidelines. We altered the acceptable follow‐up rate for long term outcomes, and we expanded the number of outcomes to be included in the planned subgroup analyses.
25 October 2010	New citation required but conclusions have not changed	New author joined the review team to update the review.
12 May 2008	Amended	Converted to new review format.
18 April 2007	New search has been performed	Search updated in February 2007. Two new trials identified. We excluded one (Dalal 2006) and included the other (Campbell 2006). The Results section was updated accordingly. With the exception of the outcome of labour length, there were no substantive changes in results or conclusions of the Review. Minor edits were made throughout. Additional text was added to the Discussion.
30 October 2006	New search has been performed	Search updated. One 'awaiting assessment' trial was assessed and included (Thomassen 2003).