(WASHINGTON) -- The Smithsonian's National Zoological Park announced Wednesday that the female giant panda Mei Xiang is exhibiting signs that she may be pregnant again.
In a press release, the Smithsonian announced the giant panda's urine showed higher levels of progesterone, an indication that she may be carrying a cub. Mei Xiang was inseminated with sperm from her mate Tian Tian in January.
"We have now entered a window of 40 to 50 days which will dictate whether a cub will be born. We have the nursery ready," said Brandie Smith, senior curator at the National Zoo.
The zoo has a webcam following Mei Xiang so everyone can observe the potentially pregnant panda.
Mei Xiang gave birth to her only cub, Tai Shan, in 2005. Before Tia Shan was born, the National Zoo had tried for three decades with another pair of giant pandas to raise cubs in captivity. They had five cubs but none lived for more than a few days.
Smith explains that it's very difficult for giant pandas to get pregnant. Females only ovulate once a year and are fertile for a small window of two days a year. Mei Xiang and Tian Tian are also a little bit romantically challenged.
"Sometimes they can't coordinate the appropriate parts," explains Smith. That's why they have a team that oversees the artificial insemination. Smith said this time all went extremely well.
With the exciting news of the higher hormone levels, Smith and her colleagues have started training Mei Xiang, reminding her what it's like to have a baby in captivity.
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