Female gorillas are sexually mature at around seven to eight years of age. However, they do not usually reproduce until they are ten years old. Males mature later than the females and are rarely strong and dominant enough to reproduce before 15 to 20 years of age.

Gorillas may breed year round.

Females are in estrus for one to two days per month and only the dominant silverback has breeding rights.

Gorillas are polygynous in nature because the dominant silverback mates with several females in his troop.