WASHINGTON (AP) - The National Zoo says it's watching its female giant panda Mei Xiang closely for a possible pregnancy.
The zoo said Monday that scientists at the Smithsonian Conservation Biology Institute confirmed that the panda has elevated hormone levels in her urine, suggesting she is either 40 to 50 days away from giving birth or experiencing a "pseudopregnancy."
A pseudopregnancy happens when a panda ovulates but does not conceive.
Mei Xiang has had five consecutive pseudopregnancies since 2007. She gave birth to her only cub, Tai Shan, in 2005.
The zoo said it is hopeful that this time the 14-year-old panda will have a cub.
Mei Xiang was artificially inseminated twice in late April.