The more babies a woman is carrying, the more likely it is that her uterus will swell, triggering contractions, says Brian Brost, M.D., associate professor of maternal/fetal medicine at the Mayo Clinic, in Rochester, Minnesota. An early due date isn't the only challenge to having multiples.
Dogs do not menstruate like humans do. Instead, they come into estrus (come into heat/season) about twice a year, once they have reached sexual maturity. This can sometimes be associated with a small amount of blood from the vulva, but it is not truly a period. Female puppies can reach sexual maturity potentially as early as six months old, although the first season (which is the closest equivalent to getting their period) is often at about nine months old.
Knowledge of the early growth periods of dogs helps to understand canine aggression. Puppies have a critical need for socialization from three weeks of age, when they can see and hear, until 14 weeks of age. Puppies should best be purchased between seven and eight weeks of age for proper socialization in the new home.f you think your dog is aggressive check the following symptoms. 1  Excessive barking; 2  A tendency to snarl, growl, or snap to protect food; 3  Overprotectiveness of possessions; 4  Fearfulness in new situations or around strangers; 5  Severe attacks on other animals, such as cats or livestock; 6  Attempts to mount people's legs;