MEMPHIS, TN - Officials at the Memphis Zoo are concerned about a pregnant panda.
They said an ultrasound of Ya Ya failed to detect a fetal heart beat or development of the fetus.
Blood tests did show progestorone, which indicated the pregnancy is there. But levels of the chemical were not as high as they should be.
Next Wednesday could be a critical day. Zoo officials say the next ultrasound should give keepers a clear indication about the condition of the panda cub.
Ya Ya was artificially inseminated in January after she and a male companion failed at mating the old-fashioned way.
The six-year-old is monitored 24 hours a day.