Egypt is known for its elaborate ancient relics and mummified tombs, but even thousands of years later, scientists still marvel over new findings.

“Shocked” scientists found the well-preserved ancient remains of a pregnant woman between 20 to 30 years old dating to the 1st century BC while examining a mummy discovered in Thebes, a city along the Nile River, in 1826.

The Polish Academy of Sciences examined the body in Poland as part of the Warsaw Mummy Project, having originally believed the mummy was a male priest. However, after using CT scans and X-rays, the team found the remains of a fetus around 26 to 30 weeks old.

“Our first surprise was that it has no penis, but instead it has breasts and long hair, and then we found out that it’s a pregnant woman,” archaeologist Marzena Ozarek-Szilke told the ᴀssociated Press. “When we saw the little foot and then the little hand (of the fetus), we were really shocked.”

Researchers, whose findings were published this week in the Journal of Archaeological Science, said this is the world’s first known case of a pregnant mummy.

“This is our most important and most significant finding so far, a total surprise,” research lead Dr. Wojciech Ejsmond explained to AP. “It opens possibilities of learning about pregnancy and treatment of complications in ancient times.”

The mummy was found in Egypt and brought to Warsaw in 1826 and the inscription on the coffin was initially named for a male priest. The body was wrapped in fabrics and was entombed with several amulets that represent the four sons of Horus, the ancient Egyptian god of kingship and the sky.