Randomization and masking
Randomization was stratified by ‘Early’ Perimenopause (EP) defined as regularWe allocated consenting participants to treatment (oral micronized progesterone 300 mg at bedtime or identical placebo) via permuted block randomization generated using Statistical Analysis Software® by a statistician (JS) unassociated with trial conduct. The trial pharmacist allocated participants through a password-protected randomization website.