Don’t break out the cigars quite yet. Zoo officials said it is “still too early to tell” if the giant panda — Mei Xiang — is pregnant or not.

They did an ultrasound Friday morning on her at the National Zoo, as they try to figure out whether she is pregnant.

Mei Xiang, the mother of the zoo’s hugely popular panda cub, Bao Bao, was artificially inseminated in the spring with semen from China. Friday will be her second ultrasound.

The zoo’s public relations team has tracked the panda’s pregnancy using the hashtag #PandaStory on social media.

But Friday’s ultrasound didn’t show much. Officials said they couldn’t tell if she was pregnant or experiencing a pseudopregnancy.

Devin Murphy, a spokeswoman for the National Zoo, said Friday after the ultrasound that Mei Xiang “willingly participates” in the exam.

“She lies down and allows the vet to touch [the ultrasound equipment] to her belly.” Her reward — pieces of apple and pears and honey water.

“She’s a pro at ultrasounds,” Murphy said.

The panda’s next ultrasound is scheduled for Tuesday.

Unlike in humans, where the egg is fertilized and the fetus starts to grow and can be measured, it isn’t so obvious with a panda, zoo officials said.

A female panda has what’s known as “delayed implantation.” She can have a fertilized egg, which can float in her uterus for weeks before it attaches to the wall of her uterus, according to zoo officials.

And there’s another complicating factor — a mama panda’s hormones and behavior are the same whether she’s pregnant or not. That is known as a “pseudopregnancy.”

Mei Xiang’s first ultrasound in June didn’t show much and that’s what zookeepers expected. It is still too early to determine if there is a fetus, zoo officials had said. But it did show she was healthy in the examination.

In June, zoo officials said Mei Xiang did well during the ultrasound, willingly lying down for the exam as she was fed honey water — a favorite of giant pandas. She also “had some fun scent-anointing herself with the ultrasound jelly after the vets finished.”

In late May, zoo veterinarians tried to do an ultrasound on Mei Xiang, but she “did not want to participate,” officials said.

Zoo officials said one reason they do the ultrasounds is to check on the panda’s health and to get her comfortable with having them done as they will become more frequent in her possible pregnancy.

Ultrasounds are the only way to confirm — definitively — if she is pregnant. If she’s pregnant, the fetus only starts to develop a few weeks before birth. The gestation period for a female giant panda is between three and six months.

This would be Mei Xiang’s third cub if she is pregnant.

Her first surviving cub was Tai Shan, who was born in 2005 at the National Zoo and now lives in China. Tai Shan’s father is Tian Tian, the 18-year-old giant panda at the D.C. zoo.

The couple’s second surviving cub is Bao Bao, a female panda who turns 2 in August.

When Mei Xiang was artificially inseminated in the spring, it was the first time frozen panda semen had made such a long journey to the zoo for breeding, according to officials.

The semen sample belonged to Hui Hui — a 9-year-old panda who lives at the China Research and Conversation Center for the Giant Panda in Wolong, Sichuan Province.

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