Abstract
The worlds of observational, clinical, and basic science collided in 2002 with the publication of results of the Women's Health Initiative (WHI), a large-scale, prospective, blinded, randomized-controlled trial designed to provide evidence regarding use of hormone treatment to prevent cardiovascular disease in menopausal women. The results of the WHI dramatically changed clinical practice, negatively impacted funding for hormone research, and left scientists to unravel the "why" of the results. Now over a decade and a half since the initial publication of the WHI results, basic and clinical scientists often do not interpret the results of the WHI with the precision needed to move the science forward. This review will 1) describe the historical background leading up to the WHI, 2) list the outcomes from the WHI, and put them in perspective with results of subsequent analysis of the WHI data and results from other prospective menopausal hormone treatment trials addressing cardiovascular effects of menopausal hormone use, and 3) articulate how the collective results are influencing current clinical care with the intent to provide guidance for designing and evaluating relevant new hormonal studies.