Serum estrogen levels of each group.

Note: Group 1A: six normal female mice without any treatment; Group 1B: six female mice were administered with nonlethal doses of CTx (busulfan 30 mg/kg, cyclophosphamide 120 mg/kg) at 3-weeks old and then transplanted with FGSCs at 6-weeks old. Group 1C: seven female mice were administered the same dose of CTx as Group 1B at 3-weeks old, but were injected with the same volume of PBS at 6-weeks old. Mice in the above three groups were killed during diestrus for the detection of estrogen at 8-weeks old.Serum estrogen levels of each group.