Effect of Foeniculum vulgare Mill. (fennel) on menopausal symptoms in postmenopausal women: a randomized, triple-blind, placebo-controlled trial

Menopause. 2017 Sep;24(9):1017-1021. doi: 10.1097/GME.0000000000000881.


Objective: Preliminary data suggest that Foeniculum vulgare (fennel) can be an effective treatment for menopausal symptoms. This trial was designed to assess the efficacy of fennel in the management of menopausal symptoms in postmenopausal women.

Methods: In this triple-blind, placebo-controlled trial, 90 postmenopausal women aged 45 to 60 years in Tehran were randomly assigned to treatment (n = 45) or placebo (n = 45) groups. The participants received 8 weeks of treatment with soft capsules containing 100 mg fennel or a placebo (2 per day for each group). The participants were followed for 2 weeks postintervention to assess the continuance of the effect of intervention. The Menopause Rating Scale (MRS) questionnaire was used to assess changes in menopausal symptoms at baseline and at 4, 8, and 10 weeks after onset of intervention.

Results: The groups recorded similar mean scores on the MRS questionnaire before intervention. After intervention, the treatment group showed a significant decrease in the mean MRS score. The results of the Friedman test showed significant differences between the mean score at baseline and those at 4, 8, and 10 weeks after onset of intervention in the treatment group (P < 0.001), whereas there were no significant differences in the placebo group. When the fennel and the placebo groups were compared, the independent t test showed significant differences in mean scores between groups at 4, 8, and 10 weeks (2 weeks postintervention; P < 0.001).

Conclusions: Fennel is an effective and safe treatment to reduce menopausal symptoms in postmenopausal women without serious side effects. More clinical trials with larger populations are required to confirm this result.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Female
  • Foeniculum / chemistry*
  • Humans
  • Iran
  • Middle Aged
  • Oils, Volatile / administration & dosage*
  • Oils, Volatile / adverse effects
  • Phytoestrogens / administration & dosage
  • Phytotherapy
  • Placebos
  • Plant Extracts / administration & dosage
  • Postmenopause / drug effects
  • Quality of Life
  • Surveys and Questionnaires
  • Treatment Outcome


  • Oils, Volatile
  • Phytoestrogens
  • Placebos
  • Plant Extracts