A lithopedion, or “stone baby”, is a rare obstetrical abnormality which can occur with a failed, usually ectopic, pregnancy. The foetus is not discharged as happens with a traditional miscarriage, but instead remains inside the woman’s belly. The body then finds itself in a curious position: it does not view the foetus as alien, and therefore is unwilling to destroy it. At the same time, it cannot leave it as the tissue will decompose and present an infection risk. Instead, the body covers the still baby over with calcium, gently petrifying it, and keeping it.
Women may carry their lithopedions for years, stretching on into several decades (a case was reported in China in 2009 of a woman who had carried her lithopedion for 60 years). While a lithopedion may cause some abdominal discomfort, the women can lead otherwise healthy lives, and carry further successful pregnancies.
Once removed, the lithopedion looks like an Inuit sculpture, or a body cast from the volcanic rock which engulfed Pompey. Strange, and strangely beautiful.
wikipedia link, 60 year old chinese lithopedion link, an image link