DC zoo: Panda behavior hints at possible pregnancy

The Smithsonian's National Zoo says its female giant panda is showing behavioral changes and is focused on building her nest as animal keepers watch for a possible pregnancy.

On Tuesday, the zoo said Mei Xiang (may-SHONG) is spending most of time inside sleeping. The zoo says that's normal toward the end of a pregnancy or a false pregnancy in which her hormone levels rise.

The zoo says Mei Xiang is also sensitive to noise and has been focused on building her nest since early July. Last week, the zoo closed part of its panda house around her den to give her a quiet space.

A Chinese panda expert performed artificial inseminations on Mei Xiang on March 30 after she failed to breed naturally with male panda Tian Tian (tee-YEN tee-YEN).