We have published a paper presenting the first known case of a pregnant ancient Egyptian mummy in April of 2021. Recently we have revealed further details that explain why the foetus is preserved and that there might be more such cases in museum collections across the world. It is necessary to look at what researchers have not paid attention to so far. We presented here our discovery in a simplified way.

Why the foetus was preserved?

The foetus remained in the untouched uterus and began to, let say, “pickle”. It is not the most aesthetic comparison, but conveys the idea. Blood pH in corpses, including content of the uterus, falls significantly, becoming more acidic, concentrations of ammonia and formic acid increase with time. The placement and filling of the body with natron significantly limited the access of air and oxygen. The end result is an almost hermetically sealed uterus containing the foetus. The foetus was in an environment comparable to the one which preserves ancient bodies to our time in swamps. The change from alkaline to acidic environment led to partial decomposition of the foetal bones, especially to washing out minerals – of which there was not much anyway, because mineralisation is very weak during the first two trimesters of pregnancy and accelerates later.

This process of bone demineralisation in acidic environment can be compared to an experiment with an egg. Picture putting an egg into a pot filled with an acid. The eggshell is dissolving, leaving only the inside of the egg (albumen and yolk) and the minerals from the eggshell dissolved in the acid. A similar dissolution of bones occurs in the acidic environment of bogs. The bog bodies sometimes do not have bones because of a similar process.

Bog body, the so called Clonycavan Man at National Museum of Ireland, Dublin, around 4th or 3rd century BC (www.wikipedia.com).

In our case, we have two different mummies, because there were two different mummification processes. The foetus was in an acidic, “bog-like” environment that later dried-up during the embalming of the mother. During the mummification process, the deceased woman was covered with natron, a naturally occurring in Egypt sodium, in order to dry the body. Subsequently it also led to drying of the uterus and foetus. So, another mummification process happened, the mineralisation of the foetus. During the drying minerals from bones, which were dissolved in the amniotic fluid, deposited in the soft tissues of the foetus and uterus. As an effect, there are the highly mineralised foetus and uterus. That is why they have high Hounsfield unit value (the Hounsfield scale is a quantitative scale for describing radiodensity) recorded in the CT data.

Computed tomography of the foetus in the mummy of the Mysterious Lady (Warsaw Mummy Project).

Of course, this is a very simplified description of complex processes that will be described in our further publication.


What we can learn from this?

First of all, foetuses in mummies may not have well-preserved bones and thus they may not be visible in X-ray and computed tomography images. That is why when looking at computed tomography images of children who died shortly after premature birth or were born dead, for example of Tutankhamun’s children, you can see bones. The entire process of preserving the remains through intentional mummification, i.e. tissue dehydration, was carried out in the same way as in the mummies and adults. The conservation status of these mummies and their computed tomography images are therefore significantly no different from other Egyptian mummies. Although here, the bones as well are less mineralized and less visible in X-ray data than in adults. This is something very different to the case of the pregnant mummy where foetal bones mostly dissolved, but the shape of the soft tissue survived.

When radiologists are examining mummies they are usually looking for bones. Our research shows that it is more important to study the shape of soft tissues in the pelvic area.

Most importantly, there is a very high probability that there may be mummies of pregnant women in other museum collections. They may have not been sufficiently analysed in this aspect. Now, considering our findings, it is only a matter of time before the next mummified pregnant woman is discovered.

The Mysterious Lady still keeps many secrets. We are still trying to explain why the foetus was left in the uterus while other internal organs were removed?

Although, the pregnant mummy became recently a kind of a “celebrity” and from the scientific point of view the whole research is fascinating, we should not forget that we are dealing here with a human tragedy that we must respect.

The Mysterious Lady died together with the unborn child, and by examining her, we restore their memory. We remember that it was a long-lived person who had her dreams, probably loved ones and was loved. Now she reveals to us the secrets she took with her to the grave.

Pregnant mummy discovery team:
Marzena Ożarek-Szilke – Co-director of the Warsaw Mummy Project, mummy researcher, anthropologist, palaeopathologist and archaeologist of Egypt.
Wojciech Ejsmond – Co-director of the Warsaw Mummy Project, Egyptian archaeologist
Stanisław Szilke – Egyptian archaeologist.
Marcin Jaworski – archaeologist, bioarchaeologist, specialist in the field of non-invasive research in archeology.
Katarzyna Jaroszewska – obstetrician gynecologist.

Visualizations and pictures were created thanks to Affidea Polska and General Electric Company.

The project was created thanks to the support of the University of Warsaw, the National Museum in Warsaw, Affidea Polska, General Electric Company and Grey Group Poland.