They got about 20 embryos from which they tried to extract stem cells and managed to produce only one stem cell line.

The researchers successfully extracted stem cells from 18 blastocysts.

South Korean researchers went further, extracting stem cells responsibly from a cloned human embryo.

Hwang claimed he and his team had extracted stem cells from cloned human embryos.

Advanced Cell scientists would then try to extract stem cells from the resulting embryo.

According to the company's website, it extracts adult stem cells exclusively from postnatal placentas.

But will others who object to destroying human embryos accept the idea of creating "biological artifacts" and extracting stem cells from them?

Scientists in South Korea report that they have created human embryos by cloning and extracted embryonic stem cells.

This month, scientists at a private Virginia fertility clinic announced that they had created embryos expressly to extract stem cells.

Social conservatives liken the research to abortion because the process of extracting stem cells from a days-old embryo results in its death.