I have a 3 month old female West Highland White Terrier, & this is the first pet dog i ever had, I want to know when it will start its PERIODS ? as i want to get it SPAYED also sometime later. Your answers will be very useful to me as well as others. Thanks.
They have to have their first cycle before you can spay them - During their cycle, get Little Boy underwear and turn them around and put the tail through the "hole" and put a diaper or women's napkin in the underwear - works wonders!
The SHOULD be spayed BEFORE ever going into heat. It will save you the possibility of pregnancy. There is absolutly NO reason to allow a dog to go through a heat cycle before spaying them. Talk to your vet, but most dogs can be spayed between 5-6months, males can be neutered earlier.
I would advice spaying you dog as soon as your vet feels it is OK. Every heat cycle she goes through can be life threating, and risk infection. Also if she never goes into a heat cycle, she will have almost no chance of breast cancer.