If you breed your otherwise healthy dog female dog once, the odds of her becoming pregnant are about 50 percent. If you've only got one shot, there are ways to improve the likelihood of pregnancy.
Timing is Everything
Females are bred between the 10th and 14th day of their heat cycle, when their bloody discharge has lessened considerably. While bleeding is the most obvious sign of heat's onset, it might have begun a day or so earlier. Constant licking of the vulva and its swelling are reliable signs that she's in heat, so pay attention to your dog's behavior. You can't breed a female dog before she's ready, as she won't accept the male.
After the male and female mate, they don't separate after the male ejaculates. Instead, they remain "tied" together for a period ranging from 10 to 30 minutes. Part of the male's penis has swollen inside the vagina so he can't withdraw. Don't try to separate them -- they will eventually part on their own.
Take your female dog to the male's home or his territory for the breeding. If your female has been bred before, you can pair her with an inexperienced dog. If this is her first time, choose an experienced male for the breeding. Place the dogs in a quiet area, leave them alone -- although you can watch from afar -- and let nature take its course.