In a now well-publicised series of events during 2002 and 2003, the Women’s Health Initiative (WHI) and other randomised controlled trials (RCTs) designed to examine the links between postmenopausal hormone therapy (HT) and the prevention of chronic disease were terminated prematurely. The estrogen plus progestin arm of the WHI was terminated when a global health index indicated overall harm and a significantly higher breast cancer risk for the treatment group, and the estrogen arm was stopped because of an increased risk of stroke in the absence of evidence of cardioprotection.