A row has erupted in Australia after Sydney's zoo announced a nine-year-old Asian elephant was pregnant.
Animal rights groups say the elephant, Thong Dee, is too young to fall pregnant, and that the zoo is "irresponsible" in letting it happen.
This was "the equivalent of allowing your 12-year-old daughter to become pregnant", said Erica Martin of the International Fund for Animal Welfare.
But keepers at Taronga Zoo say they took expert advice and acted on this.
"We took our advice from the experts in elephant reproduction," says Lucy Melo, senior keeper at the zoo.
"And based on their findings, when they came here and did elephant reproductive assessments... they suggested that all of the elephants were reproductively viable, and that they actually recommended Thong Dee for immediate breeding."
But Ifaw says under captive breeding plans, elephants should be at least 11 years old before conceiving.
If all goes well, the birth will be the first by a captive elephant in Australia, which the zoo described as a "historic event" on Thursday.
Thong Dee, who is five months into her 22-month pregnancy, is reported to be the first elephant to become pregnant while in captivity in Australia.
She was part of a group of Asian elephants imported from Thailand two years ago.