How Many Babies Do Mice Have? The Answer Might Surprise You

A female mouse can have anywhere from 3 to 14 babies, often called pups, at a time, though most litters fall in the 6 to 8 range. Since mice can have babies as many as ten times per year, a single mother could produce about 70 offspring all by herself.

With sufficient food and safety, a colony of mice can explode into a huge problem faster than most people would believe possible, undermining sanitation and spreading out to nearby homes or businesses. In practice, most colonies are somewhat limited by the environment, but even a few pups can quickly become a serious mouse infestation.

Baby mice are usually tiny and pink. They are born blind and hairless, so they need nursing from their mother before they are ready to start moving around. They depend heavily on her and her milk, so removing the mother generally eliminates the newborns as well.

Juvenile mice open their eyes and finish growing their hair around the time they are two weeks old, at which point they start leaving the nest to find their own food. Most mice finish maturing in another 2 to 4 weeks, and then they look for mates and start breeding.

Baby mice are not particularly dangerous. They do not move around much, and they do not have dangerous natural weapons. They are usually born blind and deaf, so they cannot even locate approaching threats very easily. Even grown mice are not especially dangerous on their own. They do not have nasty claws or aggressive biting habits unless you pick them up.

The danger is what they carry. Mice often carry diseases that pass from parent to child, and that is where the real risk lies. An exploding population, with several new mothers reaching maturity every few weeks, can spread dozens or hundreds of disease-carrying young across an increasingly wide area that people inhabit. Many of them also carry fleas that bite humans and spread disease further.