The breeding season of eastern wood rats depends on the climate. Those in warmer climates (e.g. Florida and Georgia) can reproduce all year, while eastern wood rats in higher latitudes (e.g. Kansas and Nebraska) breed from early spring to mid fall. Their estrous cycle lasts between 3 and 8 days, while gestation lasts between 32 and 38 days. One to six young are born in each litter, and the female may become pregnant again after a week. Females can have up to three litters in a year, with two being normal. They can also sometimes reproduce in their first year, as they reach sexual maturity before males. Females are solely responsible for the young. Females and males fight when they come across each other. If the male wins, copulation occurs, but if the female wins, the male is usually killed during fighting.