Urinary tract problems....if spayed to early?

I have heard that if you spay your dog before age 6 month they could have urinary problems.Is this true????

I know that with very early spaying there can be incontinence issues. That is generally associated with VERY early spaying - like 8 weeks. Getting your dog spayed at 5 months will help insure that you avoid that first heat cycle and shouldn't cause any incontinence issues.

I do not believe that spaying too early contributes to urinary tract problems. The main cause of urinary tract problems are caused by urine that is too alkali (not acidic enough to prevent the growth of bacteria) and there are a number of contributing factors to this. I believe that right now "pediatric spay/neuters" are a hot topic among veterinarians throughout the US - and it seems that more and more vets are favoring it.
Personally, I have two male dogs. My male pit bull was neutered at 3 months of age. He is now 3 years old and he has never had a UTI in his life. On the other hand, I have a male mixed breed dog who was neutered at 8 months of age. He is now 1 1/2 years old and he has suffered two bladder infections and has undergone surgery to remove bladder stones.
I believe hereditary and the breed of the dog, as well as the dog's diet has alot more to do with its succeptibility to urinary tract problems than early spay/neuter does.

Only if they have an extremely inverted vagina (ie. problems with vaginitis).