7789 PCOS and probiotics - a randomized controlled trial with a comparison to metformin

Abstract Disclosure: B.M. Obermayer-Pietsch: None. B. Valentin: None. B. Luegger: None. R. Regina: None. C.W. Haudum: None. V. Tandl: None. Polycystic ovary syndrome (PCOS) has a complex association not only with gonadal hormones, but also with insulin resistance and the gut – showing a decreased alpha diversity of the microbiome in PCOS women. Based on our previous investigations, we conducted a randomized controlled trial (RCT) using probiotics (OMNi-BiOTiC®, Institut Allergosan) and placebo daily, compared to a metformin group over 6 months. In this RCT, we included 112 women with PCOS, defined by Rotterdam criteria. Clinical and biochemical characterisation covered medical history with cycle abnormalities, Ferriman–Gallwey (FG) Score and anthropometric data. Hormonal profiles included gonadal hormones with a focus on androgens and AMH. Oral glucose tolerance tests (oGTT) with parallel insulin/c-peptide determinations and stool sampling for microbiome determination at every visit were done. Study participants were randomized 2:1 for probiotics/placebo or metformin (Glucophage®, Merck) and further 1:1 between probiotics and placebo for 6 months followed by a voluntary 6 months period on probiotics only. NGS for microbiome profiles was carried out. 93 PCOS women completed the study, 19 drop-outs for various reasons including 6 pregnancies were recorded (5 in the probiotic/placebo group, 1 in the metformin group). Participants were 27±5 years old, obesity with a BMI >30 was found in 35% of them. Initial cycle duration ranged from 22 to 200 days, 18% had amenorrhoea. Hirsutism was present with a mean FG score of 12,7±7,71. Mean levels (±standard deviation, reference range, no units depicted) for total testosterone were 0,38±0,15 (0,14-0,77), SHBG 54,1±29,0 (19–117), free testosterone 3,2±3,1 (0,45-2,19) and AMH 8,9±4,8 (0,17-7,37). Initial oGTTs showed insulin resistance prevalent in 43%, with an overall reduction to 36% at visit 2. Weight loss over 6 months was documented in 37%, cycle abnormalities decreased overall to 14%. Group comparisons and microbiome characterisation are ongoing. No serious adverse reactions related to the study medication were recorded. All intervention products were well tolerated in our PCOS study cohort. Based on the intended cycle normalisation, 6 pregnancies were recorded. Metabolic changes were seen both in the probiotic/placebo and in the metformin groups, with fewer changes in the placebo group despite nutritional counselling. Microbiome changes were recorded in both intervention groups. Presentation: 6/3/2024