An international group of reproductive experts plans to launch a serious effort to clone humans to provide children to infertile couples.

A viable embryo, probably created using stem cells or other cells taken from an adult, could be available for implantation in the woman's uterus within 18 months, said Dr. Zavos, an Italian researcher at The Andrology Institute of America and the Kentucky Center for Reproductive Medicine and In Vitro Fertilization in Lexington, Kentucky.

Zavos, a 25-year veteran in the reproductive field, hosted a conference on Thursday in Lexington where he and Italian fertility doctor Severino Antinori announced plans for the scientific coalition to clone humans.

"This is going to be the first serious effort," Zavos said in a telephone interview. "I do know various individual groups that are acting on their own, but they lack the support."

Scientists have cloned sheep, beginning with "Dolly" in Scotland in 1997, as well as mice and cows, but any suggestions that human clones are next have been met by outrage within the scientific community and in political and religious circles.

"As revolutionary as it may sound, as fictional as it may sound, it will be done. It's a genie that is out of the bottle and will be controlled," Zavos said.

He said 10 infertile couples have volunteered to participate, including an American pair who cannot conceive because the man's testicles were severed in an accident.

Zavos said his group would hold a conference in Rome in March, to which a cardinal from the Vatican would be invited. The Roman Catholic Church is opposed to human cloning. The consortium would operate in an unnamed Mediterranean country.

The scientists plan to use regular cells or undifferentiated stem cells from the husband and insert them into a woman's egg that has been stripped of its genetic material. The cell would be stimulated to divide and create an embryo equipped with all the specialty cells that make up a copy of the man, and then implanted in the wife's uterus.

The wives could also be the ones cloned, depending on the couple's choice, he said.

"We have a great deal of knowledge. We can grade embryos, we can do genetic screening, we can do quality control," Zavos said.

"It's not the easiest thing. The stability of the genetic information is what's important. We're cloning a human being now, we're not trying to create a Dolly. You don't want to create a monster," he said.

To create animal clones, scientists frequently made hundreds of failed attempts to develop viable embryos. Medical ethicists have posed the possibility of cruel failures in human cloning, where genetic abnormalities result in grotesque fetuses unable to survive outside the womb.

Antinori has sparked a furor in Italy by helping postmenopausal women become "granny moms," and has also pioneered a technique to help sterile men by "cultivating" their nascent sperm cells inside the testicles of mice.