‘Stone Baby’: How the rare phenomenon occurs? Explained

A

stone baby

is a condition known as

lithopedion

which is very rare. It occurs when a fetus in the womb dies and calcifies inside the mother’s body. This rare condition is said to occur through undiagnosed or untreated

ectopic pregnancy

. The calcification process, known as lithopedion formation, acts as a natural defense mechanism, preventing the mother’s body from absorbing the dead fetal tissue, which could lead to infection or sepsis.
The fetus should be alive for at least 3 months before the bones can calcify and the fetus protects itself from infections by covering it with a layer of calcium.

Abdominal pregnancy

Also known as abdominal pregnancy, the fetus growing outside the uterus – like the fallopian tube, ovary, and cervix is dangerous and fatal. According to statistics, only a small percentage of abdominal pregnancies in the body have been able to protect itself when the fetus dies by turning into a ‘stone’. In rare cases, abdominal pregnancies have delivered babies prematurely.

Types of lithopedion

There are 3 types of lithopedion.:
Lithokelyphos: The egg membrane is calcified, but the embryo can decompose
Lithokelyphopedion: Both the embryo and the egg membrane are calcified
True lithopedion: Only the fetus is calcified

Diagnose

Lithopedions can remain undetected for years because they rarely show symptoms. However, a small bump appears and it also causes abdominal pain or discomfort. Medical imaging techniques like X-rays or ultrasounds are typically used to diagnose a lithopedion.

FAQ

What is ectopic pregnancy?
An ectopic pregnancy occurs when a fertilized egg implants and grows outside the uterus.
How rarely do lithopedions occur?
Lithopedions are very rare and occur in 0.0054% and to date in medical literature, it has been recorded 300 times.
Why do lithopedions occur?
The exact cause of lithopedion formation is not fully understood and is believed to be a complex interplay of factors, including the size of the dead fetus, the location of the ectopic pregnancy, and the mother’s immune response.

The history

In 2019, less than 300 lithopedions were documented in 400 years of human history. However, lithopedion is not a new word and study suggests that it was found in 1100 BCE in burial grounds.
A case reported in 1996 noted that the lithopedion was discovered in an 85-year-old woman who had four other babies. It was mentioned by a doctor as an ‘incomplete abortion’ when the woman was 41 years old and the fetus remained in the abdomen for almost 44 years.
Another case reported in 2014 noted lithopedion in a 77-year-old woman who had never been pregnant at all.