This is a two-part study:~The first part is the Efficacy Study mainly designed to evaluate the frequency and severity of vasomotor symptoms [VMS] in both hysterectomized and non hysterectomized postmenopausal participants after treatment with two doses of E4 (15 mg or 20 mg) or placebo for 12 consecutive weeks. Thereafter, treatment will proceed for a total duration of up to 53 weeks, to continue the evaluation of secondary efficacy, safety and the effect on the endometrium. For endometrial protection, all non-hysterectomized subjects will receive treatment with 200 mg progesterone (P4) once daily for 14 consecutive days, after completion of the E4/placebo treatment.~The second part is the Safety Study designed to evaluate the general safety, secondary efficacy (lipid and glucose metabolism, health-related quality of life [HRQoL] and treatment satisfaction [TS]) after treatment with E4 20 mg for up to 53 weeks in hysterectomized and non hysterectomized postmenopausal participants. For endometrial protection, all non-hysterectomized subjects will receive treatment with 200 mg progesterone (P4) once daily for 14 consecutive days, after completion of the E4 treatment.
This is a two-part study designed to evaluate the effect of Estetrol (E4) 15 or 20 mg, or placebo on the severity and frequency of vasomotor symptoms (VMS) (Efficacy Study Part) and the safety of E4 20 mg (Safety Study Part).