The Effect of Vitex Agnus - Castus Plant on Some Markers of Oxidative Stress, Lipid Profile and Insulin Resistance in Women with Polycystic Ovary Syndrome: A Randomized, Double-Blind Controlled Clinical Trial Study.

The short version

This randomized, double-blind, placebo-controlled trial with 60 women explored whether a standardized extract of Vitex agnus-castus (also called chasteberry or chaste tree) changes oxidative stress, blood fats, insulin resistance and visible symptoms in polycystic ovary syndrome (PCOS). PCOS is a common hormonal condition marked by irregular periods, excess androgens and often insulin resistance. Oxidative stress, an imbalance between damaging free radicals and the body's antioxidant defenses, is described by the authors as feeding a cycle with insulin resistance that worsens PCOS and raises long-term diabetes and heart risk. The women, aged 18 to 45 and treated at a hospital in Arak, Iran, were randomly assigned to 12 weeks of either Vitex tablets (5.8 mg of extract a day) or identical placebo tablets, 30 per group. All kept taking their usual metformin and birth-control pill. Blood tests measured antioxidant and oxidant markers, glucose, insulin, cholesterol and liver enzymes. Ultrasound measured ovary size, the Ferriman-Gallwey score rated excess hair growth, and menstrual frequency compared observed periods with expected ones. Compared with placebo, the Vitex group had higher total antioxidant capacity (0.60 to 1.10 mM versus no change, p < 0.001) and lower total oxidant status, a damage marker (MDA) and an oxidative stress index (all p < 0.001). Insulin resistance (HOMA-IR) fell from 6.40 to 0.98 versus 6.72 to 1.33 with placebo (p < 0.05), HDL cholesterol rose from 50 to 60 mg/dL (p < 0.001), LDL fell, and the hirsutism score dropped from 10.7 to 7.8 while rising on placebo (p < 0.001). Menstrual frequency rose to 0.955 of expected periods versus 0.844 (p = 0.046). Triglycerides, catalase and right ovary volume did not change significantly, weight and body mass index were unchanged, all 60 women completed the study, and no adverse events were reported. The authors view Vitex as a promising complement to standard care and note limits: 12 weeks, one center, convenience sampling, self-reported adherence and no hormone measurements such as LH, FSH or SHBG. Participants stayed on metformin and oral contraceptives, some table values are reported with unusually large effect sizes that look inconsistent with the text, and the authors call for longer, larger trials with several doses and mechanistic endpoints.

Key findings

• In a 12-week trial of 60 women with polycystic ovary syndrome (PCOS), a standardized Vitex agnus-castus (chasteberry) extract at 5.8 mg a day raised total antioxidant capacity from 0.60 to 1.10 mM while placebo stayed flat (p < 0.001).
• Insulin resistance (HOMA-IR, a calculation from fasting insulin and glucose) fell more with Vitex than placebo (p < 0.05), HDL cholesterol rose from 50 to 60 mg/dL (p < 0.001), and the hirsutism score for excess hair growth fell from 10.7 to 7.8 while it rose on placebo (p < 0.001).
• Menstrual frequency, the share of expected periods that occurred, rose to 0.955 with Vitex versus 0.844 with placebo (p = 0.046); triglycerides and catalase did not change significantly.
• All women kept taking their usual metformin and birth-control pill, so effects are as an add-on; the trial was single-center, 12 weeks long, and no hormone levels such as LH, FSH or SHBG were measured.

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