Figure 5: Effect of exogenous melatonin on circulatory level of plasma progesterone in PCO rats showing recovery with a significant increase of progesterone as compared to control groups of rats; Histogram represents Mean ± SE; n=6; Con: Control, L: Letrozole, L+Mel=Letrozole+Melatonin, Mel: Melatonin. Con vs. L=p<0.01, Con vs. L+Mel=p<0.05, Con vs. Mel=p<0.05, L vs. L +Mel=p<0.05.