First Heat Cycle

Question
QUESTION: When does a Golden usually have their first heat cycle? I had read somewhere that it is 18 months...but we have a 7 month old who I believe just entered her first heat cycle.
ANSWER: Yes, 7 months is quite likely.  Didn't your vet suggest spaying her by 6 months?  I hope with your knowledge of dogs, you are not thinking of breeding her.  You are now stuck with all the hassle of going through it.  Most vets will not spay her now until it is all over.  The mess, the flaky behavior, and the risks of getting loose including getting killed besides bred.  As the cycle advances, there is no telling the desperate efforts she will make to get loose.  I certainly hope you realize 7 months is entirely too young to be bred.  

Any information on the positive side of breeding her is just as unreliable as that she wouldn't come into heat until 18 months.  If you insist on such a foolish venture, at least read some books.  It is not an easy way to make some money.

---------- FOLLOW-UP ----------

QUESTION: How long will the heat cycle last?  No, my vet did not suggest spaying her by 6 months....and no it was never our intention to breed her in the first place. She is only outside when someone else is out there with her as it is...so we have no fears of any dogs getting to her or her getting killed.  

Answer
The worst of it should be over in about 3 weeks.  The swelling and flaky behavior may take another month to fade.  

I want to make it very clear, not to expect normal behavior.  You may open the door with her on the far side of the room, and suddenly she is going out where your legs had been.  No 2 dogs are the same.  She could continue her usual good behavior or go berserk.  I see many questions from people like you that weren't expecting problems, and the dog had other plans.  

I really fault the vets for not doing more to educate inexperienced dog owners.  After all, how many times were you in there for shots?  There are various reasons why we slaughter 10,000,000 dogs each yours for lack of homes.  That upsets me.  One of the easiest ways to reduce it is to educate inexperienced dog owners like you to spay/neuter their pets.  Cutting out the accidental breedings would be a good start on the problem.  

It would be much easier for me to just give short questions like yours a factual answer addressing what was asked.  I feel obligated to try to reduce the misery from breedings we don't need.