Our Privacy/Cookie Policy contains detailed information about the types of cookies & related technology on our site, and some ways to opt out. By using the site, you agree to the uses of cookies and other technology as outlined in our Policy, and to our Terms of Use.


The Number of Offspring in Rats

i NA/AbleStock.com/Getty Images

Rats do not live long -- 2 to 3 years, tops -- but during their short lives they can produce many family members. Once they're sexually mature, at the age of 3 or 4 months, a male-and-female brown rat pair can have as many as 2,000 babies in the course of a year.

Rat Reproduction Cycle

A female rat is receptive to impregnation about 15 times a year, for a six-hour period each time. In that short, six-hour time span, a female can mate with many males. A mother rat has many litters during the year, with a dozen or more babies in each one.