The number of babies a monkey can have in its entire life varies significantly depending on the species of monkey and several biological factors. On average, monkeys can give birth to one baby at a time, although some species may occasionally have twins or even triplets. The gestation period for most monkey species is similar to that of humans, lasting around 5 to 6 months.
In terms of reproductive lifespan, many monkeys reach sexual maturity between 2 to 5 years of age and can reproduce until they are around 15 to 20 years old, depending on the species. If we consider that a monkey may reproduce several times a year, the total number of offspring can range from a handful to several dozen throughout its lifetime.
For example, a female rhesus macaque might have 5 to 10 offspring during her reproductive years. In contrast, larger ape species, which are closely related to monkeys, tend to have longer intervals between births. So while some monkeys can have multiple babies over their lifespan, the exact number can differ widely based on species, health, environment, and other factors.