That would account for all the children and babies and even fetal material that vanished.

Recent advances have allowed for less invasive testing methods based on the presence of fetal genetic material in maternal blood.

Generally, the fetal material is reabsorbed into the woman's body.

To perform C.V.S., doctors gently pull slender hairs, or villi, from the developing placenta and analyze the fetal genetic material that is contained in the villi.

"If we had to go back to human fetal material on a continuing basis, that would be a concern," said Gary L. Snabel, president and chief executive of Layton.

However, the clinic itself has been the subject of investigation because of at least three complaints of incomplete abortions - fetal material left in the womb - Mr. Langevin said.

Abortion - Complete Complete abortions, induced or spontaneous, occur when all fetal and placental material is expelled before 20 weeks' gestation.

It is also possible to obtain a prenatal diagnosis for an embryo or fetus in the womb, using fetal genetic material acquired through chorionic villus sampling.

So even though the Patagonian skulls are fetal material, they can help scientists understand more about titanosaurus anatomy and evolution.

"The fetal material in question would be taken from dead fetuses that have been legally aborted."