It is possible but, I thought leos normally bred at the end of a cooling off period. Mine always laid eggs in late febuary or early march. One way you can tell is by candling her. Hold her up to a bright focused light and look into her abdomen area. if you can see to large oval shaped masses on either side...you could have a momma on the way! Another thing to consider is her getting fat by over eating or being aggressive and eating any and all foods and letting the male get none. There are to many variables to single in on at the moment. Try candling and see if that works.
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1.0 Green Iguana
1.0 Bearded Dragon
0.1 Blizard Leopard Gecko
1.1.1 Corn Snakes (2 Blood Red, 1 Orange Amelanistic)
1.1 Ball Python