[gemy]

haemogiosarcoma is rather rare in Yorkies. The research I have read is yes there is a worrisome increase in this cancer but it is more applicable to large breed dogs - of note the Golden Retreiver.

The risks of pyrometra on the other hand are of a high concern - especially with unbred females and as they age. Each year tends to increase that risk.

I will also point out that breast cancer rises as well. Your girl has had all her growing well behind her and baring other contra indicators (of which your vet should inform you) then she is best spayed. At least this is the decision I would make for my female dogs.