Had a heifer 12 months old, 4 months bred. Gave her a shot of lute and she passed the fetus through. Now she is the last heifer not to breed. She has been with my bull since mid December. 2 weeks ago Vet said she might be bred or just a little swollen in heat. Anyone had a problem with a cow not breeding back after using lute or being bred too young? The lute was given in October.