Menopause is a natural process all women go thru beginning at about the age of fifty. Symptoms of menopause include hot flashes, night sweats, menstrual cycle changes, vaginal dryness and thinning, bone density loss, mood swings, weight gain, and more. Research in the past twenty years has indicated the use of synthetic hormones to treat menopausal symptoms may come with dangerous side effects such as increased chances of heart attack, stroke, and cancer. More women have turned to herb based phytoestrogens to treat the symptoms. This paper provides an overview of the favorable human based studies on herbs to treat menopause. Potential plants include: soy and its isoflavone constituent, black cohosh, red clover, anise and fennel along with the anethole constituent, flaxseed, chasteberry, evening primrose, licorice, sage, passionflower, and valerian. Also discussed are dosages based on the studies and potential side effects of each herb. Mentioned in the appendix are studies showing no improvement in symptoms compared to the placebo.
Human studies with favorable results were searched for in google scholar and PubMed. Meta analyses were found which reviewed multiple studies. Studies in which an herb was not more effective than the placebo in treating menapausal symptoms are listed in Appendix 1.
Menopause happens when a woman’s ovaries stop releasing eggs, and less estrogen and progesterone are produced at around the age of 50 years (FDA, 2017). Symptoms of menopause can include: hot flashes and night sweats, changes in frequency and length of menstrual cycle, vaginal drying and thinning, bone density loss (osteoporosis), mood swings, hair loss, cardiovascular disease, urinary incontinence, and weight gain. Synthetic hormones used to treat menopause may pose a variety of health concerns. Several studies have shown the following risks: increased chances of blood clots, heart attacks, stroke, breast cancer, endometrial cancer, and gallbladder disease (FDA, 2017). One study, called The Women’s Health Initiative (WHI), lasted 15 years and studied 161,800 postmenopausal women, finding hormone replacement therapy increased heart disease and the risk was not worth the benefits of reducing menopausal symptoms (Writing Group for the Women’s Health Initiative Investigators, 2002). Side effects of taking synthetic hormones can also include: bloating, breast tenderness, headaches, nausea, mood changes, and vaginal bleeding (WebMD, 2016). More women have turned to herbs to treat menopause symptoms with less harsh side effects. When treating with herbs, it is important to know their effectiveness based on research beyond just anecdotal evidence as well as the proper dosage and any known contraindications.
Plant estrogens, called phytoestrogens, are produced by plants such as legumes and certain whole grains and seeds. Phytoestrogen may stimulate and/or block estrogen in the body, reacting differently than the actual estrogen hormone by affecting the estrogen receptors, and each individual will absorb and metabolize phytoestrogens in different ways, varying the response and health effects (Setchell et al, 2003). Phytoestrogens taken in food quantities are generally considered safe, but quantities taken as a medical herb supplement are still being researched (The National Women’s Health Network, 2015).
This legume of the Fabaceae family is useful for its isoflavone content, and of all the plants reviewed, soy showed the most promising research for reducing menopausal symptoms. Soy can be taken as a food, such as a vegetable protein, milk beverage, flour, or cereal, or there are also isolated isoflavone supplements available. As a food, soy has been taken daily in Asian countries with little side effects for thousands of years (National Women’s Health Network, 2015). Fermented soy products like miso and soy sauce are easier for the body to digest and absorb isoflavone content (Hutchins, Slavin, & Lampe, 1995). As soy milk, 10-80 grams of milk with an isoflavone content of 40-120 mg daily can be taken (Ulbricht, 2010). In Asian countries where women eat about 50-100 mg of soy isoflavones per day, incidences of hot flashes are about 50% lower than among American women who eat an average of less than 1 mg per day (Thomas et al, 2014). However, due to its estrogenic effect, soy taken in large quantities, and especially taken as an isoflavone supplement, should be avoided with hormone sensitive conditions (Ulbricht, 2010). Some research has suggested excessive intake of soy isoflavones can increase breast cancer recurrence. However, a 2013 systematic review of 131 articles including 40 RCTs, 11 trials, and 80 observational studies found a lack of evidence of harm, but indicated more studies are necessary to confirm the safety of use of over 100 mg of isoflavones a day in women who have had breast cancer (Fritz et al, 2013).
Research has shown that the effectiveness of soy taken to relieve hot flashes may be related to a patient’s ability to convert the isoflavone: daidzein to S-equol (Newton et al, 2015). Related to menapausal research, a review of 55 articles and 16 studies summarized that soy isoflavones showed slight and slow effects on reducing menopause hot flashes (Li, Lv, Xu, & Zheng, 2015). In another meta-analysis of 17 randomized, controlled trials it was concluded that isoflavones reduced hot flushes in menopausal women (Howes, Howes, & Knight, 2006). Below is a list of favorable studies:
This is a woodland perennial shrub growing to eight feet tall with white cluster flowers and large serrated leaves. Roots and rhizomes are black in color during the Autumn season, and this is the part of the plant used for herbal therapy. It has been widely used in Europe to treat hot flashes, and found in a USA supplement called Remifemin (The National Women’s Health Network, 2015). The Remifemin tablet contains 1or 2 mg of 27-deoxyactein and is taken twice daily for menopausal symptoms (Ulbricht, 2010). In preparing the herb, the dosage is 40 – 200 mg per day of the dried rhizome, divided into three times a day; long term use has not been studied thus it is not recommended for longer than six months until further research (Ulbricht, 2010). Possible contraindications are related to its hormone like action, and it may be inappropriate for women with hormone sensitive conditions, as well as liver disorders (Ulbricht, 2010). Based on a meta-review of research, black cohosh was deemed inappropriate for use during pregnancy and lactation due to a potential labour-inducing effect, hormonal effect, emmenagogue effect, and anovulatory effect (Dugoua et al, 2006). In addition, it may interfere with the following medications: tamoxifen, chemotherapy drugs, blood pressure medications, lipitor, aspirin, blood thinners, hepatotoxic drugs, and cytochrome P450 3A4 (Petersen, 2016 & Natural Medicines, 2017). Overuse may also cause gastrointestinal upset (Natural Medicines, 2017). In addition, there is a possibility that excessive use of black cohosh may be associated with liver toxicity (Mahady et al, 2008).
A few meta-reviews on black cohosh were found. In 2010, nine randomized placebo controlled trials were reviewed and data showed that black cohosh improved symptoms of menopause, with more research on the effectiveness and safety of the herb being warranted (McCusker, 2010). A review of eight human studies showed black cohosh to be safe and effective in treating menopausal symptoms (Lieberman, 1988). Below is a list of several more human studies on black cohosh:
The purple round flower head of this common perennial weed of the Fabaceae family has been used historically as a menopausal symptoms remedy. Biochanin, formononetin, and genistein are three phytoestrogenic isoflavones found in red clover. In studies, between 40 – 160 mg of red clover isoflavones (as in the product Promensil) have been taken per day (Ulbricht, 2010). The fresh flowers can also be prepared as decoction to extract the minerals by simmering one ounce of fresh herbs in a stainless steel pot with one pint of water until it reduces to ¾ of a pint of water. Cool, strain, and store in the refrigerator for up to three days (Petersen, 2016). Adult dosage for the decoction is up to 4 Tablespoons up to 4 times a day (Petersen, 2016). As far as possible contraindications, red clover may increase the risk of bleeding and interfere with anticoagulant medications and aspirin due to coumarin and isoflavone content (Natural Medicines, 2016). It may also interfere with antiretroviral drugs, estrogen containing medications, diabetic medications, and drugs that metabolize in the liver (Natural Medicines, 2016). It can have possible adverse interactions with the following diseases: breast cancer, hormone cancers, hormone conditions, coagulant disorders, protein deficiencies, and surgery (Natural Medicines, 2016).
Promising research has warranted the possible use of red clover to treat hot flushes. In a meta-analysis reviewing seventeen articles, it was concluded that there is a marginally significant effect of T. pratense isoflavones for treating hot flushes in menopausal women with no adverse side effects for short term use and no evidence on long term use (Coon, Pittler, & Ernst, 2007). In a double blind, randomized, placebo controlled study with 30 women of the product Promensil®, hot flashes were reduced with a supplement of 80 mg of red clover isoflavones per day (van de Weijer & Barentsen, 2002). In a clinical randomized, triple-blind trial conducted on 72 menopausal women,it reduced menopausal symptoms at a dose of 45 mg of red clover isoflavones capsules per day for eight weeks (Salehi et al, 2013). Unfortunately, some of the human studies on this subject were poorly designed or short in duration and there have been other published studies with conflicting results; further research is necessary (Ulbricht, 2010).
This phenol methyl ether is found in the essential oil of certain plants of the Apiaceae family such as anise (Pimpinella anisum) and fennel (Foeniculum vulgare). It is also found in licorice and star anise, both of different plant families. In a study of essential oils of eleven Pimpinella species with anethole as a major compound, even the species with the low anethole still showed estrogenic activity (Tabanca et al, 2004). A 1980 article by Albert-Puleo discusses fennel and anise, and its main constituent of anethole as an active estrogenic agent that can be used to increase milk secretion, promote menstruation, facilitate birth, alleviate male climacteric, and increase libido.
Related to menopause, a double-blind clinical trial of 72 women who took 330 mg capsules of Pimpinella anisum three times a day for four weeks demonstrated a reduction in hot flashes (Nahidi, Kariman, Simbar, & Mojab, 2012). In a double blind randomized controlled trial on 60 postmenopausal women, a vaginal cream with fennel applied once a day for eight weeks reduced vaginal atrophy (Yaralizadeh et al, 2016). In a triple-blind, placebo-controlled trial, 90 postmenopausal women took 100mg of fennel twice a day for 8 weeks and showed significant reduction in menopausal symptoms (Rahimikian et al, 2017).
Natural Standards indicates there is not enough available research to determine a safe internal dose of anise (Ulbricht, 2010). Fennel can be maken as a tea up to three times a day by crushing fennel seeds and steeping 2 grams with 6 ounces of boiled water for 5-10 minutes (Petersen, 2016). As it relates to the essential oil, anise and fennel should be avoided with estrogen dependent cancers, sensitive skin, and may affect the strength of some birth control pills (Lis-Balchin, 2006, & WebMD, n.d.). The oils should also be avoided during pregnancy and breastfeeding (Ulbricht, 2010). As an oil: it is not advised to exceed a maximum dose of 3 drops, three times per day, for over two weeks as anethole and phenolic ethers can reduce circulation and cause disorders to the circulatory and nervous system (Petersen, 2015). Further, Pimpinella anisum caused neuronal hyper-excitability in snails and could be contraindicated in those with epilepsy (Janahmadi et al, 2008). Epileptic seizures were reported with use of fennel oil (Ulbricht, 2010)
Also called linseed, flax comes from a small weed of the Linaceae family. One tablespoon of dried flax, whole or bruised, can be mixed with a glassful of water and taken up to three times per day (Natural Standard, 2010). Flaxseed at a dose of 40 g per day for two months reduced mild menopausal symptoms and lowered glucose and insulin levels in 25 hypercholesterolemic menopausal women in a randomized crossover study (Lemay et al, 2002). Excessive use of flaxseed may cause gastrointestinal discomfort, fullness, and flatulence. Further, flax may affect the absorption of the following medications and conditions: acetaminophen, antibiotics, anticoagulants, antiplatelets, antidiabetes meds, antihypertensives, estrogens, furosemide, ketoprofen, metoprolol, bleeding disorders, diabetes, gastrointestinal obstructions, hormone related cancers and conditions, hypertension, hypotension, and high blood sugar (Natural Standard, 2016). The linamarin constituent found in the raw flaxseed, if taken in excess, can cause poisoning (Petersen, 2016).
These berries come from the chaste tree, a perennial deciduous aromatic tree of the Verbenaceae family. A dose of about 4 mg of dried extract or 600 mg of dried fruit have been taken daily (Natural Standard, 2010). The essential oil from the leaf of chaste berry showed reduced menopausal symptoms (Lucks, Sorensen, & Veal, 2002). Another study of sixty postmenopausal women that was randomized, double blind, and placebo controlled, showed chasteberry taken for eight weeks reduced hot flushes (Abbaspoor, Hajikhani, & Afshari, 2011). Chasteberry should be avoided with hormone sensitive cancers, in vitro fertilization, Parkinson’s, and psychotic disorders including Schizophrenia (Natural Medicines, 2016). In addition, it may interfere with the following drugs: contraceptives, dopamine agonists, estrogens, metoclopramide, and antipsychotics (Natural Medicines, 2016).
The root and rhizomes of this perennial plant from the Fabaceae family are used. Glycyrrhizic acid is a constituent of the plant that can be unsafe in excess, and deglycyrrhizinated liquorice (DGL) has had the glycyrrhizin content removed (Ma et al, 2009). A dosage used has been DGL tablets of 380-1140 mg taken three times a day, licorice powder root at a dose of 1-4 g total in a day, divided into three doses (Natural Standard, 2010). Excessive doses may cause sodium retention and potassium depletion (ACHS, 2017). Further, it could interfere with the following medications: antihypertensives, cisplatin, corticosteroids, cytochrome substrates, digoxin, diuretics, estrogens, ethacrynic acids, furosemide, midazolam, warfarin, cardiac glycosides, laxatives, grapefruit juice, potassium, and testosterone (Natural Standard, 2016). Research has shown some potential in the use of licorice to treat menopausal symptoms. In a randomized, double blind, clinical trial study with 60 menopausal women, licorice was more effective than hormone replacement in reducing the duration of hot flashes (Menati, Khaleghinezhad, Tadayon, & Siahposh, 2014). Licorice showed estrogenic activity that reduced menopausal symptoms over hops related to its liquiritigenin content (Hajirahimkhan et al, 2013).
Sage of the Lamiaceae family has been used for centuries in Europe as a medicinal herb (Ulbricht, 2010). A dosage of 120 mg of sage extract (along with 60- mg of alfalfa extract) was taken safely in a study daily for up to three months to treat menopause (Ulbricht, 2010). In a multicenter clinical trial of 71 patients, a fresh sage preparation taken daily for eight weeks reduce hot flushes (Bommer, Klein, & Suter, 2011). In a randomized controlled triple blind trial of 84 women, sage reduced the frequency of hot flashes in menopausal women (Sadeghi et al, 2013). As an essential oil, it is not intended for internal use, can cause skin irritation, and should be avoided with the fragile population (Lis-Balchin, 2006). Sage, cedar, thuja, and hyssop essential oil showed convulsant and neurotoxic activity in mice related to the constituents camphor, thujone, thuja, and pinocamphone (Millet et al, 1981).
Evening primrose of the Onagraceae family is a plant whose flower blooms in the evening. In a randomized clinical trial of 56 menopausal women using 500 mg of encapsulated evening primrose oil twice a day for six weeks, hot flashes and other menopausal symptoms were reduced (Farzaneh, Fatehi, Sohrabi, & Alizadeh, 2013). Evening primrose should be avoided with seizure disorders, mental illness medications, and two weeks before surgery with anesthesia; it may also interfere with medications to treat blood pressure, mental illness, depression, blood thinners, and arthritis (Ulbricht, 2010).
Passion flower of the Passifloraceae family is a vine like plant that has beautiful, aromatic, purple, Summer flowers. While there is not enough clinical evidence to recommend the best dose, up to two grams daily of the dried herb, or 1-4 mL of the tincture at 3-4 times a day, and teas or infusions have been taken (Ulbricht, 2010). In this randomized clinical trial of 54 women, passion flower reduced hot flashes (Kazemian, Sereshti, Forouzandeh, & Akbari, 2006). Use of the herb has caused drowsiness, and may interfere with some medications (Ulbricht, 2010).
This plant’s rhizomes and roots have shown to be useful in the treatment of insomnia. Hot flashes were also reduced in two human studies. Adult dosage is up to three times a day of the following: up to 3 mL of a fluid extract, up to 1 tsp of a powder, up to 6 Tbsp of an infusion, and up to 5 mL of a tincture (Petersen, 2016). Studies have shown it safe taken in short term time periods up to 28 days (Natural Medicines, 2016). In a double blind clinical trial performed on 48 women, valerian was effective in treating hot flashes (Kazemian, Banaeian, Parvin, & Delaram, 2006). In another double blind clinical trial, 68 menopausal women took 255 mg valerian capsules 3 times a day for 8 weeks and showed that valerian effectively reduced hot flashes compared to placebo (Mirabi & Mojab, 2013).
Of all the plants reviewed, soy seems to have the most research demonstrating safe use over the long term to treat menopausal symptoms. Additional herbs have promising research, like black cohosh and red clover, but more is necessary. Below is a summary:
More women, concerned about risks of synthetic hormones, are turning to herbs to treat menopausal symptoms. There have been some good human studies demonstrating the use of soy, black cohosh, and other herbs in reducing symptoms, but more research is necessary. Many of the studies have a small number of participants or the herbs are administered for a short duration of time. There are also conflicting studies demonstrating no improvement in symptoms compared to the placebo. Further, it is important for women to be aware of the proper dose and possible contraindications with taking herbs. Dosages as taken like food from dietary sources are safer than manufactured supplements with higher amounts of isolated constituents. As in soy, people have been eating it as food for thousands of years with little risk of side effects; while it is still unknown what the risk of phytoestrogen supplements may have on health, and especially hormone sensitive conditions. Further, the effectiveness of phytoestrogens in treating menopause may be different across individuals based on genetics, diet, and lifestyle.
List of human studies on herbs to treat menopause with outcomes no better than placebo:
Abbaspoor, Z., Hajikhani, N. A., & Afshari, P. (2011). Effect of Vitex agnus-castus on Menopausal Early Symptoms in Postmenopausal Women: A Randomized, Double Blind, Placebo–Controlled Study.
Albertazzi, P., Pansini, F., Bonaccorsi, G., Zanotti, L., Forini, E., & De Aloysio, D. (1998). The effect of dietary soy supplementation on hot flushes. Obstetrics & Gynecology, 91(1), 129-135.
Albert-Puleo, M. (1980). Fennel and anise as estrogenic agents. Journal of Ethnopharmacology, 2(4), 337-344.
Bai, W., Henneicke-von Zepelin, H. H., Wang, S., Zheng, S., Liu, J., Zhang, Z., … & Liske, E. (2007). Efficacy and tolerability of a medicinal product containing an isopropanolic black cohosh extract in Chinese women with menopausal symptoms: a randomized, double blind, parallel-controlled study versus tibolone. Maturitas, 58(1), 31-41.
Bommer, S., Klein, P., & Suter, A. (2011). First time proof of sage’s tolerability and efficacy in menopausal women with hot flushes. Advances in therapy, 28(6), 490-500.
Burke, B. E., Olson, R. D., & Cusack, B. J. (2002). Randomized, controlled trial of phytoestrogen in the prophylactic treatment of menstrual migraine. Biomedicine & pharmacotherapy, 56(6), 283-288.
Carpenter, J., Gass, M. L., Maki, P. M., Newton, K. M., Pinkerton, J. V., Taylor, M., … & Shifren, J. L. (2015). Nonhormonal management of menopause-associated vasomotor symptoms: 2015 position statement of The North American Menopause Society. Menopause, 22(11), 1155-1174.
Cheng, G., Wilczek, B., Warner, M., Gustafsson, J. Å., & Landgren, B. M. (2007). Isoflavone treatment for acute menopausal symptoms. Menopause, 14(3), 468-473.
Coon, J. T., Pittler, M. H., & Ernst, E. (2007). Trifolium pratense isoflavones in the treatment of menopausal hot flushes: a systematic review and meta-analysis. Phytomedicine, 14(2), 153-159.
Dugoua, J. J., Seely, D., Perri, D., Koren, G., & Mills, E. (2006). Safety and efficacy of black cohosh (Cimicifuga racemosa) during pregnancy and lactation. Can J Clin Pharmacol, 13(3), e257-e261
Farzaneh, F., Fatehi, S., Sohrabi, M. R., & Alizadeh, K. (2013). The effect of oral evening primrose oil on menopausal hot flashes: a randomized clinical trial. Archives of Gynecology & Obstetrics, 288(5).
FDA (6/14/17) Menopause and Hormones: Common Questions. Retrieved in July, 2017. Retrieved from: https://www.fda.gov/ForConsumers/ByAudience/ForWomen/ucm118624.htm.
Fritz, H., Seely, D., Flower, G., Skidmore, B., Fernandes, R., Vadeboncoeur, S., … & Sabri, E. (2013). Soy, red clover, and isoflavones and breast cancer: a systematic review. PloS one, 8(11), e81968.
Hajirahimkhan, A., Simmler, C., Yuan, Y., Anderson, J. R., Chen, S. N., Nikolić, D., … & Bolton, J. L. (2013). Evaluation of estrogenic activity of licorice species in comparison with hops used in botanicals for menopausal symptoms. PLoS One, 8(7), e67947.
Howes, L. G., Howes, J. B., & Knight, D. C. (2006). Isoflavone therapy for menopausal flushes: a systematic review and meta-analysis. Maturitas, 55(3), 203-211.
Hutchins, A. M., Slavin, J. L., & Lampe, J. W. (1995). Urinary isoflavonoid phytoestrogen and lignan excretion after consumption of fermented and unfermented soy products. Journal of the American Dietetic Association, 95(5), 545-551.
Janahmadi, M., Farajnia, S., Vatanparast, J., Abbasipour, H., & Kamalinejad, M. (2008). The fruit essential oil of Pimpinella anisum L.(Umbelliferae) induces neuronal hyperexcitability in snail partly through attenuation of after-hyperpolarization. Journal of ethnopharmacology, 120(3), 360-365.
Kaari, C., Haidar, M. A., Júnior, J. M. S., Nunes, M. G., de Azevedo Quadros, L. G., Kemp, C., … & Baracat, E. C. (2006). Randomized clinical trial comparing conjugated equine estrogens and isoflavones in postmenopausal women: a pilot study. Maturitas, 53(1), 49-58. Lemay, A., Dodin, S., Kadri, N., Jacques, H., & Forest, J. C. (2002). Flaxseed dietary supplement versus hormone replacement therapy in hypercholesterolemic menopausal women. Obstetrics & Gynecology, 100(3), 495-504.
Kazemian, A., Sereshti, M., Forouzandeh, N., & AKBARI, N. (2006). Effects of Passion Flower on Hot Flash in Menopausal Women Supervised by Esfahan Health Centers, 2002.
Kazemian, A., BANAEIAN, S., Parvin, N., & Delaram, M. (2006). The effect of valerian on hot flash in menopausal women.
Li, L., Lv, Y., Xu, L., & Zheng, Q. (2015). Quantitative efficacy of soy isoflavones on menopausal hot flashes. British journal of clinical pharmacology, 79(4), 593-604.
Liske, E., Hänggi, W., Henneicke-von Zepelin, H. H., Boblitz, N., Wüstenberg, P., & Rahlfs, V. W. (2002). Physiological investigation of a unique extract of black cohosh (Cimicifugae racemosae rhizoma): a 6-month clinical study demonstrates no systemic estrogenic effect. Journal of women’s health & gender-based medicine, 11(2), 163-174.
Lieberman, S. (1998). A review of the effectiveness of Cimicifuga racemosa (black cohosh) for the symptoms of menopause. Journal of women’s health, 7(5), 525-529.
Lucks, B. C., Sørensen, J., & Veal, L. (2002). Vitex agnus-castus essential oil and menopausal balance: a self-care survey. Complementary Therapies in Nursing and Midwifery, 8(3), 148-154.
Ma, S. K., Bae, E. H., Kim, I. J., Choi, K. C., Kim, S. H., Lee, J., & Kim, S. W. (2009). Increased renal expression of nitric oxide synthase and atrial natriuretic peptide in rats with glycyrrhizic‐acid‐induced hypertension. Phytotherapy Research, 23(2), 206-211.Contra-indicated for hypertension, diabetes, liver and kidney disorders, cardiovascular disease (ACHS, 2017).
Mahady, G. B., Dog, T. L., Barrett, M. L., Chavez, M. L., Gardiner, P., Ko, R., … & Sarma, D. N. (2008). United States Pharmacopeia review of the black cohosh case reports of hepatotoxicity. Menopause, 15(4), 628-638.
Mirabi, P., & Mojab, F. (2013). The effects of valerian root on hot flashes in menopausal women. Iranian journal of pharmaceutical research: IJPR, 12(1), 217.
McCusker, Jane MD, D. (2010). Efficacy of black cohosh-containing preparations on menopausal symptoms: a meta-analysis. Alternative therapies in health and medicine, 16(1), 36.
Menati, L., Khaleghinezhad, K., Tadayon, M., & Siahpoosh, A. (2014). Evaluation of contextual and demographic factors on licorice effects on reducing hot flashes in postmenopause women. Health care for women international, 35(1), 87-99.
Millet, Y., Jouglard, J., Steinmetz, M. D., Tognetti, P., Joanny, P., & Arditti, J. (1981). Toxicity of some essential plant oils. Clinical and experimental study. Clinical toxicology, 18(12), 1485-1498.
Nahidi, F., Kariman, N., Simbar, M., & Mojab, F. (2012). The study on the effects of Pimpinella anisum on relief and recurrence of menopausal hot flashes. Iranian journal of pharmaceutical research: IJPR, 11(4), 1079.
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Newton, K. M., Reed, S. D., Uchiyama, S., Qu, C., Ueno, T., Iwashita, S., … & Lampe, J. W. (2015). A cross-sectional study of equol producer status and self-reported vasomotor symptoms. Menopause, 22(5), 489-495
Osmers, R., Friede, M., Liske, E., Schnitker, J., Freudenstein, J., & Henneicke-von Zepelin, H. H. (2005). Efficacy and safety of isopropanolic black cohosh extract for climacteric symptoms. Obstetrics & Gynecology, 105(5, Part 1), 1074-1083.
Petersen, D. (2016). Course Material: Herb502 & Herb503: Advanced Herbal Materia Medica and Advanced Herbal Materia Medica II. www.achs.edu
Pockaj, B. A., Loprinzi, C. L., Sloan, J. A., Novotny, P. J., Barton, D. L., Hagenmaier, A., … & Wisbey, J. A. (2004). Pilot evaluation of black cohosh for the treatment of hot flashes in women. Cancer investigation, 22(4), 515-521.
Rahimikian, F., Rahimi, R., Golzareh, P., Bekhradi, R., & Mehran, A. (2017). Effect of Foeniculum vulgare Mill.(fennel) on menopausal symptoms in postmenopausal women: a randomized, triple-blind, placebo-controlled trial. Menopause.
Sadeghi, A., Bakhshi, M., Behboodi, Z., Goodarzi, S., & Haghani, H. (2013). Effect of Sage extract on hot flashes in postmenopausal women. Complementary Medicine Journal of faculty of Nursing & Midwifery, 2(4), 324-335.
Saghafi, N., Mahmoodinya, M., Ayati, S., Behdani, F., Shakeri, M. T., & Rakhshandeh, A. (2013). Comparison of Effects of Black Cohosh and Fluoxetine in Treatment of Menopausal Symptoms. Iranian Journal of Obstetrics, Gynecology & Infertility, 15(32).
Salehi, K., Ehsanpour, S., Zolfaghari, B., Salehi, Z., & Honargoo, M. (2013). Effect of red clover Isoflavones extract on menopausal symptoms. Journal of Gorgan University of Medical Sciences, 15(2).
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