The San Diego Zoo made the disappointing announcement Tuesday afternoon - Bai Yun is not pregnant.
Bai Yun, who has been off exhibit since breeding with Gao Gao in April, has been monitored by zookeepers.
While they were watching her behavior and hormone levels during that time, they noticed signs that the Giant Panda could have been pregnant.
But after careful analysis, they determined she was not expecting.
Bai Yun, who turns 20 next week, has already given birth to five healthy pandas: Hua Mei (1999), Mei Sheng (2003), Su Lin (2005), Zhen Zhen (2007) and Yun Zi (2009).
The zoo says she'll be returned to the zoo's panda exhibit Wednesday and the public can view her Saturday when the zoo opens at 9 a.m.