Looks like we could be on #PandaWatch again!

The Smithsonian National Zoo is closing its panda exhibit Friday so that Mei Xiang can have some quiet during the final stages of her pregnancy or pseudopregnancy.

On Friday, the zoo reported that the 19-year-old Panda was showing behaviors commonly attributed with pregnancy or pseudopregnancy. She's spent most of her time sleeping, building a nest in her den and eating less.

According to the Zoo, "during the later stages of a pregnancy or pseudopregnancy, a very sleepy Mei Xiang will settle and sleep for much longer periods, and if she is pregnant the panda team wants her to give birth inside where they can quickly provide help if necessary."

Veterinarians are tracking changes to her uterus with weekly ultrasounds. The only way to know if a panda is pregnant is to see a fetus on an ultrasound.

She was artificially inseminated back in May.

Here's a little explainer on panda pregnancies:

Unlike in humans, the implantation of a fertilized egg for a panda can occur months after ovulation. It’s a phenomenon referred to as embryonic diapause or delayed implantation. Here, the eggs start to divide and then fetal development stops. At this point, the embryo floats around in the uterus until, at a later stage, it attaches to the uterine wall and gestational development continues. Some embryos implant shortly after fertilization and pandas give birth in as little as three months; other times it can even take six months to see signs of a viable pregnancy. With the implantation comes a surge in progesterone—which scientists refer to as a secondary hormone rise.

You can watch Mei Xiang's progress here: https://nationalzoo.si.edu/webcams/panda-cam