The primary objective of the clinical trial is to demonstrate superiority of BHR401 (oral micronized progesterone) versus placebo as a monotherapy for moderate to severe VMS in postmenopausal women. Three different doses of BHR-401 (200 mg, 300 mg or 400 mg) will be tested against placebo in hierarchical order, starting with the highest dose. Superiority will be defined as a significant (significance level α = 0.05) reduction of moderate to severe VMS frequency compared to placebo at treatment week 12 (the primary efficacy endpoint of the study).