Washington (CNN)Giant panda Mei Xiang gave birth Saturday, the Smithsonian's National Zoo announced. It was relatively quick: About an hour after her water broke.
National Zoo panda gives birth
"Mei Xiang reacted to the cub by picking it up. The panda team began preparing for a birth when they saw Mei Xiang's water break at 4:32 pm, and she was already having contractions. The sex of the cub won't be determined until a later date," the zoo said in a press release.
The panda team is monitoring both mother and cub via its panda cams. She could be seen snuggling the cub.
At a news conference Saturday evening, zoo officials said the cub is vocalizing and looks well from what they can tell. There was no announcement of a name for the cub, nor any indication when that might come.
Experts will perform a neonatal exam on the cub when they are able to retrieve it, the zoo said, adding it may take a few days.
"All of us are thrilled that Mei Xiang has given birth. The cub is vulnerable at this tiny size but we know Mei is an excellent mother," zoo Director Dennis Kelly said in a release. "Thank you to all of our excellent keepers, veterinarians, researchers and Chinese colleagues who contributed and therefore deserve credit for this conservation success."
On Wednesday, the zoo tweeted an ultrasound of Mei Xiang's that showed a fetus, confirming she was believed to be pregnant.
At that time, the cub was about 4 centimeters long.
Two weeks ago, zoo experts saw Mei Xiang was sleeping more, eating less and building a nest. Those indicators become more pronounced last week zoo spokeswoman Devin Murphy told CNN.
Mei Xiang was artificially inseminated on April 26 and 27. Keepers used semen both from a giant panda in China as well as one living at the zoo, Tian Tian. DNA analysis will determine who is the father.
Mei Xiang, who is expected to spend almost all of her time in the next two weeks in her den with her newborn cub, has given birth to two surviving cubs -- Tai Shan, born in 2005 and now living in China, and Bao Bao, born in 2013 and who still lives at the zoo until she turns 4. She will then be sent back to China.