An Egyptian mummy, who was first believed to have been a male priest, has been revealed as a pregnant woman.
This is the only known example of an embalmed pregnant Egyptian mummy and was discovered by Polish scientists.
The discovery was made by the research team at the Warsaw Mummy Project. The research has also been published in the Journal of Archaeological Science.
The project where scientists use technology to examine artefacts housed at the National Museum in Warsaw started back in 2015.
When the project started, scientists believed that the mummy belonged to a man priest. However, they later discovered it was a woman in the later stages of pregnancy.
The mummified remains of the woman were first donated to the University of Warsaw back in 1826. Since then, researchers from the mummy project have dubbed the woman as the Mysterious Lady of the National Museum in Warsaw because of conflicting accounts around her origins.
The unknown mummy of the woman was alleged to have been found in royal tombs in Thebes. However, that might not have been the case, as researchers say it was common in the 19th Century to falsely ascribe antiquities to famous places to increase their value.
Inscriptions on the elaborate coffin and sarcophagus had led 20th Century experts to believe the mummy inside was that of a male priest named Hor-Djehuti. However, scientists believe the mummy was at some point placed in the wrong coffin by antiquity dealers during the 19th Century when looting and re-wrapping of remains were not uncommon.
Experts on the project believe that the remains of the pregnant mummy are most likely of a high-status woman between the age of 20 and 30. It is also believed that the woman died during the 1st Century BC.
Upon announcing the find, scientists revealed in the written journal that "Presented here is the only known example of a mummified pregnant woman and the first radiological images of such a foetus."
The team discovered the estimated age of the foetus between 26 and 30 weeks by using the foetus head circumference.
Team member, Wojciech Ejsmond of the Polish Academy of Sciences, stated that "This is our most important and most significant finding so far, a total surprise."
There were another four bundles of wrapped and embalmed organs found within the mummy's abdominal cavity, along with the foetus, which had not been removed from the uterus. Scientists are still baffled by the fact that the foetus had not been extracted and embalmed separately.
The mummy has been described to be "in a well-preserved condition", but damage to the neck and wrappings indicate that the mummy was targeted for valuables.
The experts say at least 15 items, including a "rich set" of mummy-shaped amulets, were found intact within the wrappings.
One of the researchers on the project, Dr Marzena Ożarek-Szilke, stated that the team hope to study small amounts of tissue to establish the woman's cause of death.