Nazarpour S, Azimi H. Comparison of therapeutic effects of fennelin and mefenamic acid on primary dysmenorrhea. Fennel oil was more effective than mefenamic acid in reduction of pain.8 The fennel oil oral drop (1% and 2%) of 0.3 to 1 mL significantly reduced the severity of pain and means of dysmenorrhea severity in dysmenorrheal patients (P < 0.05), without any significant effect on fatigue, dizziness, diarrhea, headache, faint, and mood changes. J Ethnopharmacol 2001;76:299–304. Fennel oil oral drop was more effective than mefenamic acid on dysmenorrheal pain.28 According to the results of clinical studies, fennel oil reduces the symptoms of dysmenorrhea, comparable to nonsteroidal antiinflammatory drugs (NSAIDs) and is more effective than vitamin E. The results of one clinical study show no superiority of fennel than placebo in clinical symptoms of dysmenorrhea. Mefenamic acid was more potent than fennel on the second and third days of menstruation (P ≤ 0.05). The bad taste and odor of fennel oil is its complication. Fennel is used by mouth for various digestive problems including heartburn, intestinal gas, bloating, loss of appetite, and colic in infants among othes. The principal estrogenic component of fennel was originally thought to be anethole, but it is now believed to be a polymer of anethole, such as dianethole or photoanethole.8, An acetone extract of F. vulgare seeds had estrogenic effects on the genital organs of male and female rats.9. Iran J Obstet Gynecol Infertil 2015;18:8–16. Progesterone as a steroid hormone along with estrogen has supportive care in body.46, 62 Its analgesic effects and anti-spasmolytic effects along with its estrogenic effects make it as suitable treatment for management of gynecological disorders. Martin KA, et al. Siahi M, Shirovi A, Heidari Nasrabadi M. Effect of fennel aqueous extract on the level of prolactin in female Wistar rat. The use of other medications to relief of symptoms were 66.7%, 41.8% and 39.9% in placebo group, fennel oil (1% and 2%), respectively. Some individuals exhibit cross-reactivity to several species of Apiaceae, characteristic of the "celery-carrot-mugwort-condiment" cross-reactivity syndrome.40 Rare allergic reactions have been reported following ingestion of fennel. Mohebbi-Kian E, Mohammad-Alizadeh-Charandabi S, Bekhradi R. Efficacy of fennel and combined oral contraceptive on depot medroxyprogesterone acetate-induced amenorrhea: a randomized placebo-controlled trial. The hair thickness was reduced from 97.9 +/- 31.5 to 75.6 +/- 26.7 microns (P<0.001). It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. A significant reduction in symptoms severity (hot flash, night sweating, heart disease, insomnia, and musculoskeletal disorders) were observed after 8 weeks of intervention by fennel oil compared with before intervention (P < 0.0001), and placebo group after intervention (P < 0.001).32 In randomized triple-blind clinical trial on 90 menopausal women, who received daily dose of 60 mg fennel oil or placebo soft capsules (twice daily) for 8 weeks. J Rafsanjan Univ Med Sci 2006;5:1–6. Physiol Pharmacol 2001;15:134–143. It may be a disorder of peripheral androgen metabolism. The compound most toxic against both species was p-anisaldehyde. All 4 subjects had serum estradiol levels 15 to 20 times higher than normal values for their ages. (fennel) on menopausal symptoms in postmenopausal women: a randomized, triple-blind, placebo-controlled trial.