When will my 5 month old black lab have her first heat/season?

Question
This is our third family dog, however we have never previously owned a labrador so we are finding out new things about her everyday. But something we do not no is when she will come into season/heat.
Is it true that it is advisable to get her spayed before she even reaches her first heat, as this will reduce the chance of cancer?
So when will my 5 month old black lab have her first heat/season?

Answer
Hello Immy and thank you for your questions,

Yes it is highly advisable to have her spayed before her first heat cycle or shortly afterwards... when shes under a year old if she isnt going to be bred is great becaause dogs that aren't spayed or bred have a 52% chance of getting cancer after there second cycle. Spay her now if you would like i wish I could have afforded to sapy my lab at that age I had 1 and a half cycles before I could afford it and well she had to be spayed dead heat because my other little male dog wasnt neutered, she developed lumps on her teats which the vet said could have turned to cancer if she wasnt altered shortly. MNy lab came in heat first at 8/9 months larger dogs are more spaced out then smaller ones.

I hope this helps if you need anythnig else feel free to ask, thanks.