Lions reproduce when a lioness in heat mates with a male from within her pride, conceives and goes off on her own to give birth. She cares for and protects the cubs on her own, and when they are 6 to 8 weeks old, she rejoins the pride.
Lionesses do not mate outside the pride. The pride may have from one to four dominant males, and the lioness mates with any one of them. A pride's lionesses often synchronize their breeding so that several have litters of cubs around the same time, so they can cooperate in rearing the cubs. When breeding commences, a male and female lion sometimes forsake eating and copulate every half hour, up to 40 or 50 times a day. After 108 to 110 days, the pregnant lioness leaves the pride to give birth alone in an isolated cave or thicket. The cubs are born blind and helpless and are unable to walk until they are about 3 weeks old. During this time, the lioness fends for herself, remaining nearby the cubs to protect them. Young lion cubs face danger from such predators as leopards, hyenas, jackals, eagles and snakes, and their mortality rate is high.
Integration of the cubs into the pride is easier if other lionesses have given birth to cubs of similar age. If there are older cubs, the larger ones dominate the smaller ones when feeding on kills, and there is a risk that the younger cubs might die of starvation. At 6 to 7 months, the cubs are weaned, and they reach sexual maturity when they are about 3 or 4 years old. At that time, males are expelled from the pride, although females usually are permitted to remain.