What Happens After Menopause? (WHAM): protocol for a prospective, multicentre, age-matched cohort trial of risk-reducing bilateral salpingo-oophorectomy in high-risk premenopausal women.

INTRODUCTION: Women at high inherited risk of ovarian cancer are advised to undergo risk-reducing bilateral salpingo-oophorectomy (RRBSO) at age 40-45 years or when their families are complete. Most women are premenopausal at this age, so RRBSO will induce surgical menopause. Despite the clear benefits of RRBSO for cancer risk reduction, much less is known about the impact on non-cancer outcomes that contribute to health and well-being and inform surveillance and management strategies.

METHODS AND ANALYSIS: This will be a multicentre, prospective cohort study of 105 premenopausal high-risk women undergoing RRBSO and an age-matched comparison group of 105 premenopausal women not planning oophorectomy or pregnancy in the next 2 years. The aim of this study is to measure the impact of RRBSO on sexual function (primary outcome) at 24 months in high-risk premenopausal women compared with the comparison group. Secondary outcomes include menopausal symptoms and menopause-related quality of life, mood, sleep quality, markers of cardiovascular disease and pre-diabetes, bone density and markers of bone turnover, and the impact of hormone replacement therapy use on these outcomes. Data analysis methods will include logistic and linear regression using general estimating equations accounting for the repeated outcome measurements within each participant.

ETHICS AND DISSEMINATION: The study has been approved by institutional ethics committees at each participating centre. Findings will be disseminated through peer-reviewed publications and conference presentations, and national and international networks of centres managing high-risk women, and will inform national and international clinical guidelines.

TRIAL REGISTRATION NUMBER: The pre-results protocol for this trial is registered with the Australian New Zealand Clinical Trials Registry (anzctr.org.au; registration no: ACTRN12615000082505).