(a) Superoxide dismutase (SOD) activity and lipid peroxidation (LPO; MDA levels) on different days of pregnancy (days 1–6) in uterus of control animals (n = 6) (r = −0.902). Selected area shows “window of implantation.” (b) Superoxide dismutase (SOD) activity and lipid peroxidation (LPO; MDA levels) on different days of pregnancy (days 1–6) in uterus of n-hexane fraction of Vitex negundo Linn leaf extract treated animals (n = 6) (r = 0.157).