The WHI: the effect of hormone replacement therapy on fracture prevention

The Women's Health Initiative (WHI) randomized, controlled trial was the first study to prove that hormone replacement therapy (HRT) reduces the incidence of all osteoporosis-related fractures in postmenopausal women, even those at low risk of fracture. The study authors concluded that the bone-friendly aspect of HRT was limited in clinical practice as possible adverse effects outweighed possible benefit. On the strength of these publications, regulatory authorities downgraded the use of HRT for the prevention of fracture to second-line therapy. This article examines the original and subsequent evidence presented by the WHI study and concludes that the restrictions placed on HRT as a bone-specific drug by regulatory bodies have not withstood the test of time and are not supported by the data of the WHI.