One 21-year-old female panda in the National Zoo fake pregnancy. The name of the panda is Mei Xiang. She shows pregnancy signs like reduced appetite and mobility.
After that, the Zoo had to close the Giant Panda House. Even though visitors could still see the other pandas.
Similarly, some smarter pandas show behavior and hormones mimic a pregnancy even if they are experiencing a pseudopregnancy. Her levels of urinary progesterone began to rise in July indicating that she would give birth to a cub or experience the final stages of pregnancy within 6 to 8 weeks.
Her hormone levels are at baseline levels and her behavior is slowly returning to normal.” The Panda House has reopened to the public.
Pandas fake pregnancies in order to receive more food and special treatment.
(Source)