Effects of supplementation with two probiotic strains (Lactobacillus helveticus and Bifidobacterium longum) on hormonal status, oxidative stress, and clinical symptoms in women with polycystic ovary syndrome: a randomized clinical trial.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder affecting women. This study investigates the impact of 8-week supplementation with two probiotic strains, Lactobacillus helveticus and Bifidobacterium longum, on hormonal status, oxidative stress, and clinical symptoms in women with PCOS. Conducted as a double-blind, placebo-controlled, randomized clinical trial, the research involved 90 women with PCOS from Shahid Beheshti Hospital, Isfahan, Iran. Serum markers were assessed before and after the intervention. After adjusting for baseline values and confounding variables, the 8-week supplementation with two probiotic strains resulted in a significant increase in sex hormone binding globulin (24.39; 95% CI (15.23,33.55) vs. -11.99; 95% CI (-20.12, -3.86) nmol/L, P < 0.001), total antioxidant capacity (125.53; 95% CI (53.78,197.28) vs. -42.90; 95% CI (-78.32, -7.48) nmol/mL, P = 0.002) and Superoxide dismutase activity (0.19; 95% CI (0.09,0.30) vs. -0.11; 95% CI (-0.18, -0.04) U/mL, P < 0.001), in the intervention group compared to the placebo. While free androgen index (-57.05; 95% CI (-80.33, -33.76) vs. 49.86; 95% CI (28.81,70.92), P < 0.001), C-reactive protein (-0.50; 95% CI (-0.95, -0.04) vs. 0.05; 95% CI (-0.39,0.50), P = 0.046), and malondialdehyde levels (- 23.69; 95% CI (-30.02, -17.35) vs. -2.70; 95% CI (-9.19,3.77), P < 0.001), significantly decreased in the intervention group compared to the placebo. Furthermore, testosterone total levels showed a decreasing trend in the intervention group, although the between-group changes were not statistically significant after baseline value and other confounders adjustment (-3.37; 95% CI (-11.85, 5.11) vs. 6.48; 95% CI (3.43, 9.53) ng/dL, P = 0.08). Regarding clinical symptoms, including acne, alopecia, and hirsutism, the between-group changes were insignificant (P > 0.05). In conclusion, these findings suggest that 8 weeks of probiotic supplementation may alleviate oxidative stress, modulate certain hormonal factors, and reduce inflammation in women with PCOS. Trial registration, the current study was registered in the Iranian Registry of Clinical Trials on 30 March 2024 (ID: IRCT20121216011763N62) ( https://irct.behdasht.gov.ir/trial/76067 ). https://irct.behdasht.gov.ir/trial/76067 .