I can tell you just from comparing two dogs one who was spayed before their just heat and one who was not by flipping them on there back with out any studies you can see that the mammarys are developed in the non spayed before first heat female and they are not in the female that was fixed before her first heat. With no developed mammarys there is a much less of a chance of mammary cancer. I have heard and seen many cases of mammary cancer. Of course every one needs to read and do there own research but upon doing mine it is simply a personal choice there is no science to back up that waiting is best. The growth plates still close and so on after being spayed. Although I do not recommend spaying before 6 months the younger they are the faster they heal and recover. I personaly have not seen anything that would make me sway from getting them fixed before there first heat.

That is quite true about the delayed closure of the growth plates.


I think that dogs just like humans are part of the same genus, and there is value to looking to large or medium breed studies for many conditions. Certainly hormones tend to act very similarly across all sizes of dogs. And an internal organ is an internal organ in all sizes of dogs.
But for osteopathic conditions it seems logical to conclude osteo configuration problems are more severely felt by large breed dogs. In fact they can be life - threatening - and certainly have severe quality of life implications.


And a Mammary Gland is the same Mammary Gland across all breeds of dogs - and there is no grand increase in this cancer with delaying a spay for one or two heats. The often quoted statistics are quite wrong - cancer mammary does not increase to 8% after even spaying after second heat. I will need to look up once again the often mis-understood and quoted study - but first only 50% of all mammary tumors are cancerous - and 50% are benign. Cancer risk does increase very very slightly after delaying one or two heats - the increase might be 8% on the .01% spaying before first heat. That means the increase is measured like this .01% goes up by 8% for simplicity at 10% increase the incident rate would go from 1% to 1.10% - a really really neglibile factor.

But there IS an increase .. For me, I prefer NO risk at all. 50% are cancerous...enough for me.

I am not a breeder and there is no reason for me to have intact dogs in my home. My dogs are in great shape and I don't for one minute buy into this whole thing about the growth plates. Maybe there is some slight difference, but it is obvious to me that it is not a huge one. I will continue to spay before the first heat. I will not put my dogs at any risk of cancer that can be avoided....that information is backed by research.

For anyone else, I would hope you would speak with your vet and get his/her feedback on this topic.

I rely on what my vet advises me. Again, I suggest you speak to your own vet before making your final decision.