Growing Baby Eggs Into Babies

IVF method that grows immature eggs may lead to greater fertility options for women

(RxWiki News) If you want to make a baby, you need a sperm and a mature egg. Until recently, scientists haven't known how to grow eggs to maturity on their own. But now they have an idea.

A recent study has shown how a chemical helps to grow eggs. If the technology can work in a human body, it could expand women's options for fertility and IVF treatments.

"Ask your doctor about fertility options."

The research, led by professor Kui Liu and his student Deepak Adhikari at the Department of Chemistry and Molecular Biology at the University of Gothenburg in Sweden, revealed a way that might improve options for in vitro fertilization (IVF) for women.

Only mature eggs can be used with IVF therapy, in which an egg is removed from a woman's body, fertilized with the sperm and then re-implanted.

But Dr. Liu and his students found a way to make immature eggs grow up in female mice.

If the same mechanism works for human women, it might expand women's options in preserving or extracting sufficient eggs.

Women and even girls being treated for cancer with chemotherapy or radiation sometimes lack options when it comes to having children later.

The chemotherapy or radiation often kills their eggs, leading to infertility.

One of the current ways to preserve fertility is to preserve women's eggs before the treatment occurs.

But young girls who have not yet hit puberty have only underdeveloped eggs, and no methods exist yet for maturing these eggs outside the body.

However, a protein molecule PTEN appears to play a role in preventing eggs from maturing, as scientists learned in a previous study.

When Dr. Liu's team used a chemical to block the PTEN molecule, the underdeveloped eggs matured into healthy, mature ones.

In fact, the team produced five healthy mice who grew from eggs they matured using this chemical to block the PTEN molecule.

They activated the mouse eggs with the PTEN-blocking chemical in mouse ovaries in the laboratory, implanted them in a female mouse to grow the eggs, fertilized the eggs using IVF and then transferred the embryo back into a host female.

The mice that were born were fertile after reaching sexual maturity and showed no symptoms for disease when they were 15 months old, which is about 70 years old in human terms.

The researchers were also able to use the chemical blocking PTEN to mature human eggs in human ovaries in the laboratory (outside of a human body).

If this technology can be harnessed for women, it would especially benefit young girls with those immature eggs who want to have children later.

The immature eggs could be extracted and frozen and then matured when needed.

But the technology could also help other women whose eggs are underdeveloped or small for other reasons.

"This discovery demonstrates that there is a realistic chance of being able to use PTEN inhibitors to activate small eggs in a test tube," Dr. Liu said. "This technique is extremely valuable for those women who have only small eggs in their ovaries and cannot be helped by IVF as things stand."

However, the development is still in the early stages of determining whether it could work for women.

Dr. Liu stated optimistically in a release that he hoped to see the method available to women in five to ten years.

It is too early to know whether the method will work in women, how it would be administered and how much it would cost.

The study was published September 24 in the journal PLoS ONE. The authors reported no external funding and no competing interests.

Review Date: 
September 28, 2012