Environmental exposure to lead and cadmium only minimally affects the redox system of the follicular fluid and the outcome of intracytoplasmic sperm injection

Abstract

The purpose of our study was to determine the influence of lead and cadmium in concentrations commonly found in the environment on the redox system of the follicular fluid (FF) and on the results of assisted reproduction. A prospective study of 113 patients with unexplained infertility who qualified for intracytoplasmic sperm injection (ICSI). Patients with moderate or severe endometriosis or poor ovarian reserve were excluded from the study. Biochemical analyses and heavy metal assays of follicular fluid and serum (blood) were followed by statistical analyses of dependencies between lead and cadmium and the components of redox system and results of assisted reproduction. A highly significant linear correlation of lead (Pb) and cadmium (Cd) concentrations in serum and in FF was stated. The number of retrieved oocytes and MII (metaphase II stage) oocytes depended on the malondialdehyde (MDA), catalase (CAT), catalase/g of protein (CAT/g of protein), and glutathione reductase (GR) concentrations. Among biochemical factors, MDA was the only factor that correlated negatively with cadmium concentration in serum and FF and simultaneously influenced the number of retrieved oocytes and MII oocytes. The fertilization rate of MII oocytes was influenced by thiol groups—SH, SH/g of protein, CAT, CAT/g of protein, and glutathione peroxidase/g of protein (GPx/g of protein). The Pb and Cd concentrations in FF did not significantly influence the fertilization rates. Lead as well as cadmium at concentrations commonly found in women of reproductive age despite some adaptive changes in the redox system in follicular fluid do not cause large changes in the ovarian follicular environment as a whole and do not significantly worsen the final results of assisted reproduction.