British archaeologist Howard Carter found the mummified fetuses when he discovered the tomb in 1922. Archaeologists assume they are the children of the teenage pharaoh, but this has not been confirmed.
The identity of their mother is also still unknown.
According to a report in New Scientist, many scholars believe their mother to be Ankhesenamun, the boy king's only known wife. Ankhesenamun was the daughter of the queen Nefertiti, who was renowned for her beauty.
"For the first time, we will be able to identify the family of King Tut," said Zahi Hawass, the head of Egypt's Supreme Council for Antiquities. "This should allow us for the first time to discover the mummy of Nefertiti," he added.
Nefertiti had six daughters with the Pharaoh Akhenaten, who abandoned traditional gods in favor of monotheism during his rule from about 1350 to 1334 BC.
The queen's mummy has never been identified.
"The DNA tests and computerized tomography (CT) scans, to be performed at Cairo University, should be finished by December," said Hawass.
Egypt has been trying to check the identity of all its royal mummies using DNA and CT scans. Tutankhamun's was one of the first mummies to be examined with the technology in 2005.
Tutankhamun, born in 1341 BC, died less than a decade after taking the throne at the age of eight or nine.