The 2017 Hormone Therapy Position Statement of The North American Menopause Society

The North American Menopause Society 2017 Hormone Therapy Position Statement Advisory Panel


The North American Menopause Society (NAMS). 2018;24(7):728-753. 

In This Article


An Advisory Panel of clinicians and researchers expert in the field of women's health and menopause were enlisted to review the NAMS 2012 Hormone Therapy Position Statement (, evaluate the literature published subsequently, and conduct an evidence-based analysis, with the goal of reaching consensus on recommendations.

NAMS acknowledges that no single trial's findings can be extrapolated to all women. The Women's Health Initiative (WHI) is the only large, long-term RCT of HT in women aged 50 to 79 years, and its findings were given prominent consideration. However, the WHI employed just one route of administration (oral), one formulation of estrogen (conjugated equine estrogens [CEE], 0.625 mg), and only one progestogen (medroxyprogesterone acetate [MPA], 2.5 mg), with limited enrollment of women with bothersome vaso-motor symptoms (VMS; hot flashes, night sweats) who were aged younger than 60 years or who were fewer than 10 years from menopause onset—the group ofwomen for whom HT is primarily indicated. In general, the Panel gave greater consideration to findings from larger RCTs or meta-analyses of larger RCTs and reviewed additional published analyses of the WHI findings; newer outcomes from smaller RCTs; longitudinal observational studies; and additional metaanalyses.

The 2017 Hormone Therapy Position Statement of The North American Menopause Society is based on material related to methodology, a review of key studies and evidence-based literature, and presentation and synthesis of evidence. It was written after this extensive review of the pertinent literature and includes key points identified during the review process. The resulting manuscript was submitted to and approved by the NAMS Board of Trustees.

A scientific background report supporting the 2017 Hormone Therapy Position Statement of The North American Menopause Society can be found online at

Explaining Hormone Therapy Risk

Clinicians caring for menopausal women should understand the basic concepts of relative risk (RR) and absolute risk in order to communicate the potential benefits and risks of HT and other therapies. Relative risk (risk ratio) is the ratio of event rates in two groups, whereas absolute risk (risk difference) is the difference in the event rates between two groups.[1]

Odds ratios (ORs; measure of association between exposure and outcome) or risk ratios of 2 and less in observational trials lack credibility and are difficult to interpret.[2] Therefore, these smaller risk ratios can have little clinical or public health importance, especially if outcomes are rare. In properly performed RCTs, smaller risk ratios may be interpreted as having greater credibility and relevance, but low risk ratios provide less assurance that biases, confounding, and other factors do not account for the findings (Table 1).[3]

Key Points

  • Odds ratios or risk ratios less than 2 provide less assurance about the findings.

  • Smaller risk ratios in RCTs have more credibility than in observational studies.