Published: May 06, 2014 12:19 PM EDT

MIAMI (AP) - A Miami mother says she was surprised to learn she was pregnant again, this time with triplets.
    
That's because Sharon Lewis is 47 and already has two older children. Doctors say it's rare for a woman her age to have conceived the babies naturally without fertility treatment.
    
Dylan, Denere and Denard were delivered early - at 30 weeks - on March 18th. Each weighed about two pounds. They were cared for in the neonatal intensive care unit at Holtz Children's Hospital at the University of Miami/Jackson Memorial Medical Center.
    
The triplets are scheduled to leave the hospital on Tuesday after a press conference.
    
Lewis, a school cafeteria monitor, says the triplets were a big surprise, but "it was a wonderful surprise."

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