Serum copper assessment in patients with polycystic ovary syndrome and tubal infertility Original paper

What was studied?

This retrospective, cross-sectional study assessed the serum copper levels in women with infertility, specifically comparing patients with polycystic ovary syndrome (PCOS) and those with tubal infertility, to evaluate copper’s association with hormonal, metabolic, and in vitro fertilization (IVF) parameters. Over five years, the study explored whether elevated copper levels correlate with PCOS clinical phenotypes and IVF outcomes, and whether copper could be a relevant biomarker in reproductive health.

Who was studied?

A total of 766 Chinese women under age 38 were included, comprising 560 women with tubal infertility (no-PCOS group) and 206 women with PCOS undergoing IVF. The diagnosis of PCOS was based on the modified Rotterdam criteria. All participants underwent their first IVF cycle at the Center of Reproduction and Genetics, Suzhou Municipal Hospital, between January 2018 and December 2022. Baseline clinical, metabolic, hormonal, and trace element data, including fasting glucose, triglycerides, cholesterol, lipoproteins, and serum copper, were collected and analyzed.

What were the most important findings?

Women with PCOS showed significantly elevated serum copper concentrations compared to those with tubal infertility. Within the PCOS group, serum copper positively correlated with body mass index (BMI) and triglycerides (TG), but not with fasting glucose, LDL, or HDL. In contrast, the no-PCOS group demonstrated a broader metabolic correlation with copper, including BMI, TG, TC, LDL, and a negative correlation with HDL. Despite these associations, serum copper levels did not significantly predict IVF outcomes such as oocyte retrieval, MII oocyte rate, fertilization, or embryo quality, once confounding variables were controlled for.

From a microbiome perspective, this study indirectly highlights the importance of copper in modulating oxidative stress and lipid metabolism, both of which influence microbial diversity. Elevated copper is known to disrupt microbial homeostasis by promoting oxidative stress and favoring the growth of pro-inflammatory species such as Desulfovibrio and Proteobacteria. Conversely, lower copper levels may favor microbial populations that support metabolic stability. These shifts may exacerbate the gut dysbiosis observed in PCOS, which is closely linked to insulin resistance, chronic inflammation, and hormonal imbalances.

What are the implications of this study?

This study underscores the clinical relevance of elevated serum copper as a marker of metabolic dysregulation in women with PCOS, though not a direct predictor of IVF outcomes. The strong correlation between copper and triglycerides suggests a metabolic link that may be mediated by oxidative stress or microbiome alterations. Given copper’s known impact on gut microbial balance and inflammatory signaling, these findings reinforce the importance of trace element assessment in PCOS, particularly in the context of metabolic health and infertility. While copper may not serve as a standalone biomarker for fertility success, its elevation in PCOS warrants further exploration in longitudinal studies to assess causality and mechanistic pathways, including copper’s effect on the microbiota–ovary axis. Clinicians should consider monitoring serum copper alongside traditional lipid profiles in PCOS management, especially in cases of treatment-resistant metabolic dysfunction.