Mei Xiang, a 22-year-old panda at the Smithsonian National Zoo in Washington DC, is expected to give birth soon. Zookeepers said on Friday they were thrilled to detect what looked like a fetus during an ultrasound check. Mei Xiang was artificially inseminated on March 22 with frozen semen collected from male panda Tian Tian. In late July, she exhibited behaviors consistent with pregnancy.