Effect of Foeniculum Vulgare (Fennel) on Sleep Quality of Menopausal Women: A Double-blinded, Randomized Placebo-controlled Trial

OBJECTIVES: Aim of present study was designed to investigate the soporific effect of fennel among menopausal women. METHODS: The present double-blinded and placebo-controlled trial examined the fennel effect on Pittsburgh Sleep Quality Index (PSQI). Total score and relevant 7 components, including sleep duration, sleep latency, use of sleeping medication, subjective sleep quality, sleep disturbances, daytime dysfunction and habitual sleep efficiency among 50 menopausal women compared to control group within a 12-week follow-up. RESULTS: The patients in both groups reported no certain side effects and all subjects completed the study. The mean actual sleep duration was 5 hours and 66 minutes. Intergroup comparison revealed no statistically significant differences in the mean total PSQI score (P = 0.439), subjective sleep quality (P = 0.826), habitual sleep efficiency (P = 0.127), sleep disturbances (P = 0.130), use of sleeping medication (P = 0.52) and daytime dysfunction (P = 0.439). A tendency toward significant between 2 groups was seen concerning the sleep duration (P = 0.059). Intergroup comparison showed significantly borderline levels (P = 0.059). CONCLUSIONS: The treatment of 12 weeks with fennel caused a slight effect that did not reach to significant. These findings should be considered cautiously because of small sample size, short-term follow-up and subjective measure of sleep quality.