The average gestation period for an elephant is approximately 22 months. Just like with humans, this is not a hard and fast rule. One elephant was pregnant for a total of 700 days — just shy of 2 years — before giving birth.
Elephants are pregnant the longest out of all of the land-dwelling animals, and theirs is close to being the longest pregnancy of all animals. Twins are very rare, and the vast majority of elephants give birth to only one offspring at a time. Calves are usually born during the wet season. They can weigh up to 260 pounds at birth. Elephants normally wait between 2 to 5 years before becoming pregnant again, but if a young elephant dies shortly after birth, the mother may become pregnant again sooner than usual.
For the first 90 days of their lives, young calves rely only on the nutrition from their mother's milk. After that period of time, they are able to begin to forage for vegetation and use their trunks to collect water. They still continue to suckle milk to supplement their diets up until the mother elephant gives birth again.