Role of Phytoestrogens in Endometriosis.

AIM

To investigate the therapeutic potential of phytoestrogens in the management of endometriosis and to elucidate their mechanisms of action based on current preclinical and clinical evidence.

METHODS

This narrative review evaluates recent studies exploring the biological activity of phytoestrogens-specifically isoflavones, stilbenes, flavonoids, and curcuminoids-in relation to endometriosis pathophysiology. Emphasis was placed on their effects on estrogen signaling, inflammation, angiogenesis, oxidative stress, and apoptosis.

RESULTS

Phytoestrogens exhibit both estrogenic and anti-estrogenic properties depending on their concentration and receptor affinity. Compounds such as resveratrol, genistein, and quercetin have demonstrated the ability to inhibit aromatase activity, downregulate pro-inflammatory cytokines (e.g., TNF-α, IL-6, and COX-2), and suppress vascular endothelial growth factor (VEGF) expression. These actions contribute to reduced lesion growth, decreased inflammation, and enhanced apoptosis in experimental models. Despite these promising findings, clinical data remain limited, and bioavailability concerns, individual variability in metabolism, and potential adverse effects-such as gastrointestinal discomfort or endocrine disruption-must be carefully considered.

CONCLUSION

Phytoestrogens represent promising adjuncts in the treatment of endometriosis due to their multi-targeted molecular actions and relatively favorable safety profile. However, their clinical application requires further validation through randomized controlled trials. Specialist supervision is recommended to ensure optimal dosing, monitor safety, and evaluate interactions with standard hormonal therapies.

© 2025 Japan Society of Obstetrics and Gynecology.