Association of Dyslipidemia With Reproductive Hormone Profiles and Menstrual Regularity in Patients With Polycystic Ovary Syndrome

Aims/Background: Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder among women of reproductive age, often accompanied by dyslipidemia. However, the direct association between dyslipidemia and reproductive hormone profiles and menstrual regularity remains unclear. This study aimed to retrospectively analyze the association of dyslipidemia with reproductive hormone levels and menstrual regularity in patients with PCOS. Methods: This was a single-center retrospective cross-sectional study that included 324 patients with PCOS who visited The First Affiliated Hospital of Soochow University between June 2021 and June 2025. Based on the inclusion and exclusion criteria, 236 patients were ultimately included. Patients were divided into a dyslipidemia group (n = 121) and a eulipidemia group (n = 115) based on their lipid profiles. General demographic data, lipid levels, reproductive hormone levels, and menstrual history were collected. Multiple linear regression was used to examine the independent associations between lipid levels and reproductive hormone levels, whereas multivariate logistic regression was used to examine the relationship between lipid levels and menstrual regularity. Results: Patients in the dyslipidemia group had significantly higher levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone (TT) than those in the eulipidemia group (all p < 0.001), significantly lower estradiol (E2) levels (p < 0.001), and a significantly higher incidence of menstrual irregularities (90.08% vs. 43.48%, p < 0.001). Multiple linear regression analysis showed that, after adjusting for age, body mass index (BMI), and homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) were independently positively associated with TT, FSH, and LH, whereas high-density lipoprotein cholesterol (HDL-C) was independently and negatively associated with TT and FSH (all p < 0.001). HDL-C was positively associated with E2, whereas LDL-C was negatively associated with E2; however, these associations did not remain significant after correction for multiple comparisons. TG and LDL-C were independently and negatively associated with sex hormone-binding globulin (SHBG) (all p < 0.01). Multivariate logistic regression analysis showed that TG (OR = 2.126, 95% CI: 1.088–4.156, p = 0.027) and HDL-C (OR = 0.153, 95% CI: 0.052–0.448, p < 0.001) were independently associated with menstrual irregularity. Conclusion: In patients with PCOS, dyslipidemia is closely associated with reproductive hormone imbalances and menstrual irregularity. TG and HDL-C levels were independently associated with menstrual regularity. Dyslipidemia is not only a metabolic abnormality but may also contribute to the development of the endocrine phenotype of PCOS. Clinical management should consider the potential value of lipid-targeted interventions in improving reproductive and menstrual outcomes.