Proposed IVF Technique Uses Three Parents

L A U S A N N E , Switzerland, July 3, 2001 -- Scientists appear to have found away that someday could allow women to become mothers after they nolonger can produce viable eggs, a potential advance in breaking thelast great barrier to fertility treatments.

Theoretically, the method could create an unlimited supply ofeggs for an infertile woman and allow her to have a child at a mucholder age. However, experts tried to play down that possibility,saying they strongly discourage post-menopausal motherhood onethical and practical grounds.

The technique, described Monday at a conference of the EuropeanSociety of Human Reproduction and Embryology in Lausanne, involvestaking a cell from an infertile woman's body, and inserting it intoan emptied donated egg. The resulting egg contains the geneticmaterial of the woman wanting the baby, not of the donor.

Still Preliminary

Scientists warned that the work is still in the preliminarystages, and it could be years before the technique produces ahealthy baby, if ever. When they fertilized the manufactured eggwith sperm, it divided once, then collapsed.

Dr. Gianpiero Palermo, a professor of embryology at the Centerfor Reproductive Medicine and Infertility at Cornell University,said that besides older women, his technique could help those whocan't use their own eggs, either because they don't have any orbecause their eggs are no good.

Such women could include those whose ovaries are removed beforecancer treatment, those who were born without ovaries or women whoreach menopause at a young age.

Some Say Potentially Revolutionary

Prominent fertility researcher Dr. Zsolt Peter Nagy, who was notconnected with the project, said the technique potentially is oneof the most important advances in fertility treatment ever.

Fertility treatments took a major step forward in 1978, when ateam led by Robert Edwards and Patrick Steptoe conquered Fallopiantube problems with the introduction of in vitro fertilization,where the egg is fertilized outside the body and implanted in thewomb.

Then, in 1992, while he was working in Belgium, Palermocircumvented the failure of sperm to swim to the womb by injectingthe sperm directly into the egg — a technique called ICSI.

The problem of declining egg supply as women age has probablybeen the biggest major challenge in fertility treatment since then,experts say.

"I am sure one day this will work," said Nagy, scientificdirector at the Central Research Clinic of Human Reproduction inSao Paulo, Brazil. Nagy is pursuing similar research.

"And if it does, it will be the biggest development, after IVFand ICSI," he said.

Edwards called the research "promising."

Others Say Genetic Abnormalities Could Occur

Others were more skeptical that manufactured eggs could producehealthy babies anytime soon, saying the technique would likelycreate gross genetic abnormalities. Scientists believe that DNAdeteriorates with age and fear that the older the cell, the morelikely the chance of major defects.

All people inherit two sets of chromosomes from their parents -one from their mother and one from their father. Normally, all thecells in the body, except the sperm and the egg, have two copies ofeach chromosome, which contain the genes.

A mature egg contains only one set of each chromosome. When acell from elsewhere in the body is inserted into an emptied egg, itthen has two sets.

To make the egg viable for fertilization, the scientists had toget rid of one of the sets of chromosomes. An electric shock splitthe pairs in half and prompted the egg to expel the unwanted set ofchromosomes, making it suitable to receive the sperm.

Roger Gosden, a fertility pioneer from McGill University inMontreal, Canada, said Palermo's technique was "plausible."

"If there's a way we can help people have a genetic childrather than a donated egg, then we should. This is interestingscience, it's very preliminary, but who knows?" he said.