LOUISVILLE, Ky. (WDRB) -- The Louisville Zoo is preparing for the birth of a really big baby.

Zoo staff are now on 24-hour watch awaiting Mikki the elephant to go into labor. Mikki has been pregnant since October 2017.

Workers are taking daily blood samples from the elephant. The zoo says when her progesterone levels drop, birth will be imminent. 

It will be the African elephant's second baby. Her first, Scotty, was born in March 2007 and died from complications of colic.

At birth, the new baby elephant will weigh roughly 200 pounds.

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