How long are elephants pregnant?

Published 8 October 2026 · By the TuskWise team

About 22 months. The Smithsonian's National Zoo gives 21.5 to 22 months for Asian elephants, the longest pregnancy of any animal, and a 2012 study of zoo elephants measured an average of about 640 days. A single calf weighing roughly 50 to 160 kg is born, and mothers usually wait several years before the next calf, which is why elephant populations recover so slowly.

The numbers

Pregnancy length	About 22 months (21.5 to 22 months for Asian elephants, per the Smithsonian; 20 to 22 months for elephants generally, per San Diego Zoo Wildlife Alliance; average about 640 days in a 2012 study)
Number of young	Usually one; twins are rare
Calf weight at birth	About 50 to 120 kg (San Diego Zoo Wildlife Alliance); 68 to 158 kg for Asian elephants (Smithsonian)
Calf height at birth	About 66 to 107 cm at the shoulder
Weaning	Usually by two to three years, sometimes not until the next calf is born
Birth interval	Three to eight years on average for Asian elephants, depending on conditions

How an elephant stays pregnant for nearly two years

In most mammals, pregnancy is supported early on by progesterone from a single corpus luteum, a temporary gland that forms on the ovary where an egg was released. Elephants were a puzzle: although they release only one egg per cycle, vets found several of these structures on their ovaries during pregnancy.

In 2012, Imke Lueders and colleagues at the Leibniz Institute for Zoo and Wildlife Research used detailed ultrasound and hormone measurements on 17 African and Asian elephants in zoos to work out what was going on. They found that elephants have two surges of luteinizing hormone before ovulation. The first creates several accessory corpora lutea without releasing an egg; the second, about three weeks later, triggers ovulation and forms the main corpus luteum. Together, an average of about five of these structures appear. If the elephant conceives, all of them grow larger once the embryo becomes visible at around day 49 and keep producing progestagens right through the pregnancy. Because the elephant placenta does not produce these steroid hormones, this set of ovarian glands appears to be the main source that sustains such a long pregnancy.

Why so long?

Large animals generally have longer pregnancies, and elephants are the largest land animals. But size is not the only reason. An elephant calf is born remarkably developed: it can stand soon after birth and walk with the herd within days, which is vital for an animal that must keep up with a family moving in search of food and water, and that may be targeted by predators such as lions and hyenas when young. Elephants are also born with a large, complex brain, and the long pregnancy gives it time to develop. Researchers have suggested that this helps calves cope with the social and physical demands of herd life from the start.

Birth and the first weeks

Females give birth to a single calf, usually with other family members gathered closely around. The newborn is covered in more hair than adults, has a short trunk it cannot yet control well, and nurses with its mouth from the mother's teats between her front legs. San Diego Zoo Wildlife Alliance says calves gain about 1 to 1.3 kg a day in their first year. Other females in the family, often older sisters and aunts called allomothers, help protect and guide the calf. By about six months calves start eating plants, and the Smithsonian notes they also eat their mother's dung for some years to acquire the gut bacteria they need to digest plant fiber. Read more about family life on our behavior page.

Slow breeding, slow recovery

Put the numbers together and elephant reproduction is extremely slow. A female may not have her first calf until her mid teens, each pregnancy takes almost two years, calves nurse for two or more years, and births are typically several years apart. Even a healthy female will raise relatively few calves over her life.

That has big consequences for conservation. When poaching or habitat loss kills elephants, populations cannot bounce back quickly. The problem is most acute for the African forest elephant: WWF notes that forest elephants reproduce more slowly than savanna elephants, and the IUCN warns that this slow reproductive rate hampers the species' recovery from a decline of more than 86% over 31 years. See elephant conservation and how many elephants are left.

The bottom line

Elephants are pregnant for about 22 months, the longest of any animal, sustained by an unusual set of hormone producing glands on the ovary. The payoff is a large, well developed calf that can walk with its family almost immediately. The cost is a very slow breeding rate, which is one reason why protecting the elephants that exist today matters so much.

Frequently asked questions

Which animal has the longest pregnancy?

Among living animals with well documented pregnancies, elephants have the longest, at about 22 months. The Smithsonian's National Zoo describes it as the longest gestation period of any animal.

How much does a baby elephant weigh at birth?

Figures vary with species and mother. San Diego Zoo Wildlife Alliance gives about 50 to 120 kg for elephants generally, and the Smithsonian's National Zoo gives about 68 to 158 kg for Asian elephant calves.

Can elephants have twins?

Rarely. Elephants usually have a single calf; the Smithsonian notes that twins occasionally occur.

How often do elephants have babies?

The Smithsonian gives an average birth interval of three to eight years for Asian elephants, depending on conditions. Because pregnancy alone takes nearly two years and calves nurse for two or more years, a female typically raises a calf every four or five years or so at best.

At what age do elephants have their first calf?

The Smithsonian reports that wild Asian elephants reach sexual maturity at around 8 to 13 years and females usually give birth for the first time in their mid teens. San Diego Zoo Wildlife Alliance gives a maturity range of 13 to 20 years for elephants in general.