When Does A Boxer Get Her First Period. It’s hard to tell when your first period will arrive. You can get your period any time between 9 and 15 and be considered totally normal!
However, some may have it as early as 4 months or as late as 15 months old. While six months is the average age of a dog’s first heat, it can vary between dogs. The exact age your fur pal will have her first period depends on her breed.