PTX3 as a key modulator of functional ovarian response in PCOS: evaluation alongside TSG-6 and ITI.

Objective: To investigate the relationship between follicular fluid pentraxin 3 (PTX-3) levels and ovarian response, embryo quality, and insulin resistance (IR) in patients with polycystic ovary syndrome (PCOS) undergoing IVF/ICSI.

Methods: A total of 130 women were enrolled and categorized into three groups: lean PCOS (n = 43), overweight PCOS (n = 42), and unexplained infertility (UEI, n = 45). Patients with endocrine disorders, chronic inflammatory diseases, or recent hormonal therapy (within 3 months) were excluded. Follicular fluid (FF) and serum PTX-3 levels were measured using ELISA. Subgroup analyses were performed according to BMI and HOMA-IR status. Correlations between FF PTX-3 and clinical, hormonal, and embryological parameters were assessed. ROC curve analysis and multivariate linear regression were used to evaluate the diagnostic and predictive value of FF biomarkers for follicular output rate (FORT).

Results: FF PTX-3 levels were significantly higher in both lean (23.31 ± 1.33 ng/mL) and overweight PCOS patients (12.54 ± 1.05 ng/mL) compared to UEI controls (7.01 ± 0.54 ng/mL; p = 0.029). Notably, PTX-3 remained elevated in lean PCOS despite a lower BMI, supporting its role in intrinsic ovarian inflammation. FF PTX-3 showed significant positive correlations with total testosterone (r = 0.580), AFC (r = 0.598), and oocyte count (r = 0.532), but was inversely associated with high-quality embryo number (r = - 0.482), 2PN count (r = - 0.312), and FORT (r = - 0.418). ROC analysis demonstrated moderate diagnostic performance of PTX-3 for predicting suboptimal FORT (AUC = 0.77; cut-off: 20.4 ng/mL). In multivariate analysis, FF PTX-3 (β = - 0.65, p = 0.001), TSG-6 (β = - 0.42), and ITI (β = - 0.37) were independent negative predictors of FORT, while AFC was positively associated.

Conclusion: Elevated follicular PTX-3 levels are linked to hyperandrogenism and ovarian reserve in PCOS, but may impair embryo quality and functional follicular response. PTX-3 may serve as a potential biomarker of ovarian inflammation and compromised oocyte competence, independent of BMI or systemic insulin resistance.