Lithopedion

A Lithopedion (Greek:litho = stone; pedion = child), or stone baby, is a rare phenomenon which occurs most commonly when a fetus dies during an ectopic pregnancy, is too large to be reabsorbed by the body, and calcifies on the outside, shielding the mother's body from the dead tissue of the baby and preventing infection. Lithopedia may occur from 14 weeks' gestation to full term. It is not unusual for a stone baby to remain undiagnosed for decades, and it is often not until a patient is examined for other conditions or a proper examination is conducted that includes an X-ray that a stone baby is found. The oldest reported case is that of a 76 year old woman, whose lithopedion had probably been present for 46 years.

Fewer than 300 cases have been noted in 400 years of medical literature.

The earliest stone baby is one found in an archaeological excavation, dated to 1100 BC. The condition was first described in a treatise by the great physician Albucasis in the 10th century AD.

A related condition is known as vanishing twin, in which the fetus is one of two or more sharing the uterus. If the fetus is older than eight weeks at the time of its death, and is retained in the uterus for at least ten weeks, it may undergo mechanical compression such that it takes on a flattened, mummified appearance with a surface texture resembling that of parchment.

References in popular culture

 * A lithopedion figures as a central plot device in Samuel Hopkins Adams' 1944 novel, Canal Town.
 * In the Nip/Tuck season three episode "Joy Kringle", a lithopedion is discovered during a routine liposuction.
 * In the Law & Order: Criminal Intent episode "In the Dark", a woman in the early stages of dementia is discovered to have a lithopedion.
 * In Will Self's novel How The Dead Live, the central character Lily Bloom meets her lithopedion son Lithy after her death.