Scientists at the National Zoo say they have detected a rise in hormone levels in the female giant panda, Mei Xiang that could indicate the panda may give birth or end a false pregnancy by early July.
The zoo says the hormone rise announced Tuesday aren't enough to know whether Mei Xiang is pregnant. Zoo veterinarians have been conducting ultrasounds twice weekly, but they have not yet detected a fetus.
Scientists say panda fetuses don't start developing until the final weeks of a gestation period.
A Chinese panda breeding expert helped zoo scientists artificially inseminate Mei Xiang in January. She and male panda Tian Tian had attempted to mate but weren't successful.