Effects of natural and plant-based therapies on menopausal symptoms: a systematic review and meta-analysis

Oscar H. Franco, MD, PhD1, Rajiv Chowdhury, MD, PhD2, Jenna Troup, MSc1, Trudy Voortman, MD, PhD1, Setor Kuntusor, MD, PhD2, Maryam Kavousi, MD, PhD1, Clare Oliver-Williams, MD, PhD2, Taulant Muka, MD, PhD1. 1Epidemiology, Erasmus MC, Rotterdam, Netherlands; 2Public Health & Primary Care, Cardiovascular Epidemiology Unit, University of Cambridge, Cambridge, United Kingdom.

Objective: The proportion of women in Western countries who use complimentary therapies to manage menopausal symptoms is estimated to be 40-50%. We aimed to determine the impact of natural and plant-based therapies on the presence and severity of menopausal symptoms.

Design: The electronic databases MEDLINE, EMBASE, and Cochrane Central were systematically searched to identify appropriate studies published up to December 16th 2015. We included randomized controlled trials (RCTs) and observational studies that assessed natural or plant-based therapies in relation to the presence of one or more menopausal symptoms, including hot flashes, night sweats, vaginal dryness and Kupperman Index. Reference lists of the included studies were searched for further identification of relevant studies.

Results: In total, 119 articles based on 113 unique studies (101 RCTs and 12 prospective non-randomized intervention or observational studies) were identified, including a total of 12,443 individual women. Based on meta-analyses of the findings from RCTs, use of phytoestrogens significantly reduced the reported number of daily hot flashes [pooled mean difference of changes: −1.26 (95%CI: −1.87, −0.65)] and significantly improved vaginal dryness score [pooled mean difference of changes: −0.31 (−0.52, −0.10)]. Individual phytoestrogen interventions such as dietary and supplemental soy isoflavones were beneficial for menopausal outcomes in general, and for number of night sweats in 24 hours in particular. Additionally, behavioral therapies, acupuncture, and several herbal remedies improved overall menopausal symptoms as measured by the Kupperman Index [pooled mean differences: −11.10 (−17.17, −5.03), −8.41 (−11.81, −5.0), and 6.72 (−8.10, −5.33), respectively]. There was substantial diversity in quality across the available studies.

Conclusion: Findings indicate that composite and certain specific phytoestrogen supplementations may confer a benefit of reducing menopausal symptoms in women. Additionally, several other plant-based and natural therapies may also effectively improve menopausal symptoms. However, owing to a generally sub-optimal quality and the heterogeneous nature of the current evidence, further rigorous studies are needed to determine their impact on menopausal health and symptoms alleviation.