Associations of Essential and Non-Essential Trace Elements’ Levels in the Blood, Serum, and Urine in Women with Premature Ovarian Insufficiency

Premature ovarian insufficiency (POI) is poorly understood, with causes identified in only 25% of cases. Emerging evidence suggests links between trace elements (TEs) and POI. This study is the first to compare concentrations of manganese (Mn), copper (Cu), zinc (Zn), selenium (Se), molybdenum (Mo), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) across urine, serum, and whole blood in women with POI compared to healthy controls (HC), aiming to explore their distribution and potential associations with POI. This cross-sectional-case-control study enrolled 81 participants (40 POI patients and 41 healthy controls) at the University Medical Centre Ljubljana, Slovenia. Blood and urine samples were collected to quantify basic biochemical parameters using standard clinical chemistry methods and concentrations of Mn, Cu, Zn, Se, Mo, As, Cd, Hg, and Pb using inductively coupled plasma-mass spectrometry (ICP-MS). Participants also completed questionnaires on socio-demographics, medical history, lifestyle, and nutrition. Data was analyzed using the Mann–Whitney U test, Student's t-tests, Fisher exact test, logistic regression models adjusted on body mass index (BMI), age, hematocrit, and Kendall's tau correlation. Women with POI had significantly higher BMI and red blood cell (RBC) indices, including hemoglobin, hematocrit, and red cell distribution width (RDW), compared to controls. A larger proportion of POI patients resided in rural agricultural areas. Liver and kidney function assessments showed no significant differences between the groups. Adjusted models revealed that POI patients had significantly lower urinary levels of Cu, Zn, Se, Mo, Cd, Hg, and Pb than controls, while whole blood Mn levels were higher. Serum Cu levels were significantly elevated in POI patients, whereas Pb, Cd, and Hg were lower. No significant differences were observed for As. Correlation analysis showed several strong to moderate associations among TEs across biofluids, but only weak correlations were found between TEs and demographic or biochemical factors. This study suggests potential associations between TEs and POI in women. Notably, most TEs (Zn, Se, Cu, Mo, Cd, Hg, Pb) were significantly lower in the urine of the POI group, while Cu, Cd, Hg, and Pb showed significant differences in both urine and serum.