It's more an interesting fact I remembered rather than disturbing @Trevor. Human body sucks but it can do bizzare things.
When a fetus from abdominal pregnancy died and too large to be reabsorbed, it calcified as a foreign body reaction. The woman can carry a "mummified" dead fetus for dozens of years (even more than 50). The phenomenon is called lithopedion (stone baby).
(Photo taken by Yiğit Sezer)