Trace element concentrations in follicular fluid of small follicles differ from those in blood serum, and may represent long-term exposure

ObjectiveTo determine the levels of elements in follicular fluid (FF) of patients undergoing IVF and evaluate the relationship between the concentration of elements in FF, follicular volume, and blood.DesignProspective blinded study.SettingUniversity-based IVF center.Patient(s)Follicular fluid/blood samples from 6/3 patients, respectively, undergoing IVF.Intervention(s)Single follicular aspirations of 33 follicles were performed. Blood samples (∼5 mL) were drawn at the time of oocyte retrieval from 3/6 patients only. The concentrations 26 elements were measured by inductively coupled plasma mass spectroscopy.Main Outcome Measure(s)Trace elements concentrations in follicular fluid and blood.Result(s)[1] Calcium and magnesium were the most abundant, followed by Cu, Zn, Fe, Cr, Rb. The elements V, Sr, Se, B, As, Pb, Al, Mo, Mn, and Cs were found in trace amounts. The elements Li, Be, Ag, Cd, Ba, Ti, Bi, U were not detected. [2] Element concentrations in small follicles frequently differed from those of large follicles. [3] Element concentrations in large follicles more closely resembled those in blood.Conclusion(s)Concentrations of elements in FF of small follicles can differ from those of large follicles in the same woman and from those of blood serum. When follicles grow they become filled with fluid of an elemental composition similar to blood. Concentrations of elements in small follicles may represent longer term element exposure, whereas those of growing follicles represents the coincident blood concentrations.