I just lost my RIR male and I need to know how long will she stay firtile for? both were just under a year old and gitting ready for the first spring laying. she had layed 5 eggs earler this year but none were firtile. can anyone help? So everone says that thay will keep fertile for 3-4 weeks. Now if she doesn't lay untill it warms up, 2 to 3 weeks or longer. does it start from the time she lays, or when the last conception took place?