Low dose estriol pessaries for the treatment of vaginal atrophy: a double-blind placebo-controlled trial investigating the efficacy of pessaries containing 0.2mg and 0.03mg estriol.

Objective: The aim of the study was to confirm the superior efficacy of estriol containing pessaries compared to placebo in the treatment of vaginal atrophy.

Study Design: In a prospective, multicenter, randomized, placebo-controlled, double-blind study, 436 postmenopausal women with vaginal atrophy (vaginal maturation index, VMI<40%; vaginal pH>5; most bothersome symptom, MBS≥65 on visual analogue scale, VAS) were treated with pessaries containing either 0.2mg estriol (N=142) or 0.03mg estriol (N=147) or with a matching placebo (N=147) for 12 weeks.

Main Outcome Measures: Primary efficacy endpoints included increase in VMI, decrease of the vaginal pH value and decrease in intensity of MBS after 12 weeks of treatment.

Results: The increase in VMI was significantly greater under 0.2mg estriol and 0.03mg estriol (46.3±17.0 and 38.4±19.4, respectively) compared to placebo (23.9±21.5; p values<0.001), vaginal pH decreased significantly more (-1.6±0.8 and -1.4±0.9, respectively) compared to placebo (-0.6±0.8; p values<0.001) and MBS intensity (VAS) declined significantly more (-52.2±23.7 and -47.1±23.4, respectively) compared to placebo (-31.8±26.3; p values<0.001). Adverse events were rare and occurred at similar rates in all three groups.

Conclusions: Superiority of estriol containing pessaries over placebo was shown in the local treatment of vaginal atrophy. Even a very low dose of 0.03mg estriol proved sufficient for local treatment of vaginal atrophy with excellent tolerability.