Experts offer theories on how dead woman could deliver baby

SAN FRANCISCO (AP) Investigators searching for a link between the bodies of a woman and an infant boy that washed ashore separately on the Richmond waterfront may find clues in an unusual medical phenomenon called ``coffin birth.''

Coffin birth is a term used by coroners for a spontaneous birth by a dead pregnant woman. It occurs when the gas that builds up naturally in the abdomen and pelvic area of a decomposing body produces enough pressure to push the unborn baby through the birth canal and out the corpse.

Boyd Stephens, chief medical examiner for San Francisco, said the term does not get much usage anymore since it was coined when bodies were much less likely to be embalmed. ``If a body is properly embalmed, it's not likely to happen,'' he said.

Stephens said that when a pregnant woman dies and her body is not embalmed, it could take weeks or even months for a post-mortem birth to take place.

``If someone is pregnant and decomposing in a temperature of 110 degrees, it will happen much more quickly than if they're decomposing in a temperature of 40 degrees,'' he said.

Another explanation for how a fetus could become separated from its dead mother is if her body was torn open in death or decomposed to the point where there was nothing to hold the baby inside, according to Stephens.

Published reports have suggested the adult body found in Richmond came ashore with no head or legs, but a Contra Costa County sheriff's deputy declined to comment on the reports.

Investigators are working to determine if the woman's body is that of Modesto resident Laci Peterson. Peterson was eight months pregnant and due to deliver a baby boy on Feb. 10 when she disappeared from her home on Christmas Eve.

(Copyright 2003 by The Associated Press. All Rights Reserved.)