(CNN)Panda Mei Xiang started showing a spike in her hormone levels last month, an indicator that she could be pregnant, the Smithsonian's National Zoo said Friday.
Zoo: Panda hormone spike could be pregnancy
Zoo spokeswoman Devin Murphy tells CNN that the hormone spike included a steroid hormone, which could either be a sign that she is having a cub or that she would experience the end of a pseudo pregnancy in 30-50 days from then. The zoo first saw the spike July 20.
This week the scientists and panda experts noticed Mei Xiang was sleeping more, eating less and started to building a nest. She started exhibiting some of these signs last week, but Murphy tells CNN they were more pronounced this week.
"Those are behaviors that are consistent with a pregnancy or a pseudo pregnancy," Murphy tells CNN.
The panda team is continuing to monitor Mei Xiang, as can most people with an high-speed internet connection on the zoo's panda cam.