The following variables were singled out as independent contributors of change in oxidative stress parameters over three measurements: the lymphocyte count (p < 0.05) as a predictor of GST levels, alanine transaminase (p < 0.05) as a predictor of the GSH-Px level and obesity (p < 0.01), and the presence of thrombophilia (p < 0.01) and the leukocyte count (p < 0.05) as predictors of GR levels. The gene discussed is GSR; the disease is Rare hereditary thrombophilia.