Correlation between intestinal flora and glucuronidase indexes and sex hormone levels and their diagnostic efficacy evaluation for premature ovarian failure

Premature ovarian failure (POF), affecting women under 40, is characterized by early loss of ovarian function with unclear pathogenesis. This study evaluates the role and diagnostic performance of intestinal flora (IF) combined with gut microbial β-glucuronidase (gmGUS) in diagnosing POF. Sixty-two women with clinically confirmed POF and 52 healthy controls were recruited. Fecal and serum samples were analyzed for IF composition (Lactobacillus,Bifidobacterium,Enterococcus,Escherichia coli), gmGUS activity, and sex hormone levels including anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2). Correlations were analyzed using Pearson's method. Receiver operating characteristic (ROC) curves were generated to assess diagnostic efficacy. POF patients showed significantly lower levels of Lactobacillus(8.27± 0.95 vs. 10.24 ± 1.24 log CFU/g), Bifidobacterium (8.18 ± 0.89 vs. 10.17 ± 1.21 log CFU/g), and gmGUS (481.82 ± 34.91 vs. 1742.17 ± 141.65 U/mL) than controls (P< 0.001). AMH and E2 were reduced, while FSH and LH were elevated in POF (all P< 0.001). gmGUS was positively correlated with E2 (r = 0.374, P< 0.05) and negatively with AMH, FSH, and LH (P< 0.001). A diagnostic model combining gmGUS, Lactobacillus, and Bifidobacterium achieved an area under the ROC curve (AUC) of 0.912 (95% CI: 0.862–0.962), sensitivity of 95.2%, and specificity of 71.2%, positive predictive value (PPV) of 3.2%, and negative predictive value (NPV) of 99.9%. this study supports the role of the gut–ovary axis in POF and proposes a promising diagnostic adjunct based on gut microbiota and enzymatic markers. Future large-scale, multicenter studies with mechanistic exploration are needed to validate these findings and explore potential microbiota-targeted interventions for POF.