Mei Xiang. (Photo by Daniel Reidel)

Better luck next year. Giant panda Mei Xiang, who had been exhibiting some signs of pregnancy, does not have a bun in the oven, the National Zoo says.

Keepers closed off part of the giant panda habitat in late August after Mei Xiang exhibited the signs of a second hormone rise in a pregnancy. She was building a nest in her den, sleeping more, eating less, and reacting intensely to loud noises.

But even then, the zoo cautioned not to get too excited, because pandas often experience “pseudopregnancies,” wherein the body appears for all intents and purposes to be expecting even though there’s no baby. It’s certainly not the first time for Mei Xiang, the National Zoo’s only adult female panda.

That secondary rise in hormone levels began July 28, meaning she would either give birth or her pseudopregnancy would end within 30-50 days of that. Her hormones returned to pre-(pseudo)pregnancy levels on September 14, but there’s no accompanying cub.

The National Zoo says that Mei Xiang either experienced a pseudopregnancy or she did conceive, but her body then reabsorbed the embryo.

Keepers performed two rounds of artificial insemination on Mei Xiang this year using the sperm of male giant panda Tian Tian, who fathered her cubs Bei Bei, Bao Bao, and Tai Shan through the process in previous years.

Now that Mei Xiang is 19, though, she’s nearing the end of her reproductive life cycle, the zoo says. Tick tock goes the biological clock, but it’s not midnight just yet: “There are pandas who have had cubs when they were older than she is now, the zoo assures us all. No pressure.

The panda habitat will return to its normal hours of 9 a.m. to 6 p.m. starting on September 16.

Previously:
Is The Giant Panda Preggers? Keepers Close Part Of Zoo Habitat, Just In Case
The Zoo’s Giant Pandas Did Not Have Sex This Year
Giant Panda Mei Xiang Might Be Ready To Breed Soon At The National Zoo
Giant Panda Tian Tian Is Feeling Horny, Restless