Polycystic Ovary Syndrome (PCOS) affects up to 20% of all women worldwide, leading to irregular menstrual cycles, fertility issues and hirsutism caused by elevated androgen levels. Further metabolic conditions and complications include insulin resistance and weight gain, type 2 diabetes, an increased risk of cardiovascular diseases and a potentially severe reduction in their quality of life. Probiotics have been investigated in PCOS as a new treatment approach, potentially reducing clinical symptoms and improving their metabolic health. However, reliable data on this topic are still scarce. This thesis summarizes the process of designing a large randomized-controlled trial (RCT), comparing probiotics with placebo and the standard treatment for PCOS, metformin, to determine their potential in reducing symptom severity. For this purpose, a pilot trial was set up in order to test the proposed methodology and select the most promising probiotic out of three distinct commercially available probiotics from Institut Allergosan, Graz, Austria. In addition, a retrospective analysis of a well-established PCOS cohort was conducted to determine the impact of each particular PCOS symptom on the metabolic health in women with PCOS, which would later be used to determine the primary endpoint of the large-scale RCT as well as the sample size calculation needed for later recruitment. The study design, including study visits, recruitment process, endpoint selection and choice of probiotic intervention, was determined based on the methods and results of these two preparatory studies. In the cohort study, women with elevated free testosterone levels were at most risk of developing insulin resistance and other metabolic sequelae, which is why free testosterone was selected as the primary endpoint measure for the RCT. Based on median free testosterone changes in the pilot trial, OMNi-BiOTiC® metabolic was selected as the probiotic of choice for the RCT. Based on the pilot trial methodologies, the RCT was then designed using additional findings from both trials. If proven successful, probiotics might become a new treatment option for women with PCOS.
Probiotic Dietary Intervention in Polycystic Ovary Syndrome – Preparation of a Randomized Controlled Trial
Borzan, V. (Author). 2026
Student thesis: Doctoral thesis