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Gerbils get reproductive when they reach sexual maturity at the age of three months.
Because the gestation period is about 24 days a healthy couple can thus produce their first litter at four months of age. The female can produce litters up to an age of 14 to 20 months. On average, a female will produce about 7 litters in her life. A female gerbil is ready to mate when she is in estrus, a certain stage in her fertility cycle. Only in estrus, she is fertile.