We don’t know our lab’s medical history, her mother was surrendered to the shelter very pregnant and ill. Half the puppies lived, their mother survived eclampsia, and they were bottle fed. We are waiting for a heat before spaying her— for bone and joint health. Our vet supports that idea, and I’ve read the UC Davis studies. Those studies just broke down results by age. Neither she or her sister have had a heat at nearly 13 months. They are lovely, petite, low energy girls. She’s a trim/slim 50 lb. Their two brothers are much larger. We know they’re purebreds by genetic testing and the family who surrendered them did confirm that. We’ve had a dog with severe hip dyplasia— a GSD—who “bunny hopped “ even as a young puppy and had a total hip replacement at one. Is it common to not have a heat at this age? All of our previous girls were spayed before any heat, so this is all a new experience. We are nervous about caring for her in heat, but want her to be as healthy as possible. Thanks!