Hope for fertility treatment as cancer drugs found to revive ovaries

A new study has revealed that cancer treatment appears to have rejuvenated the ovaries of patients and increased their stock of immature eggs, an "astonishing" result which overturns the generally held view that women are born with a limited supply of eggs to last their lifetime.

The result could have major implications for the treatment of infertility and premature menopause in women.

According to the research carried out by a group of Scottish team, the scientists were able to discover evidence that proved that the drug therapy turned back the developmental clock, making the ovaries look as if they belonged to pre-pubescent girls.

The researchers is still investigating whether the newly generated immature eggs have the potential to mature and gain the capacity to make babies.

14 women having chemotherapy donated ovarian tissue for research.

Eight women, between the age range of 16 to 29, had been treated for Hodgkin's lymphoma with a drug combination known as ABVD.

Researchers got a shock when they examined the tissue, expecting to see evidence of damage by the drugs but the treatment yielded surprising numbers of non-growing follicles containing immature eggs that appeared to be newly formed.

There were far more of the eggs than could be seen in ovarian tissue from women who received other forms of chemotherapy, or even healthy women of the same age.

Lead scientist of the research, Professor Evelyn Telfer, from the University of Edinburgh, said: 

"This was an astonishing result that we didn't expect. It's not what we set out even to look at.

"The tissue looked more like that of pre-pubescent than adult ovaries. It wasn't just the fact that there were more immature eggs, it was the way they were organised and clustered. There were features that we only see in the young ovary.

"We don't know what the mechanism is. Our working hypothesis is that the drugs destroyed eggs in the ovaries and at the same time induced the activation of cell populations in a way that's compatible with making new eggs."

Although the study only involved a few patients, the findings published in the journal Human Reproduction could be "far reaching", she added.

The research team are now conducting laboratory tests to see if the eggs have the potential to mature, either naturally or through artificial means.

"Can we activate them and get them to form functional eggs? That's the question," Prof Telfer said.

"We have the menopause, and that's a reality. I wouldn't go as far as saying we could overcome the menopause. But there is the exciting prospect that this research might lead to strategies for helping women who experience the menopause prematurely."

Further studies will be carried out aimed to look at the separate impact of each of the four drugs in the combination - adriamycin, bleomycin, vinblastine and dacarbazine.

At birth, a girl's ovaries hold one to two million follicles, the "sacs" within the ovaries that contain immature eggs. By the time she reaches puberty, only about 400,000 remain.

With each menstrual cycle, about 1000 follicles are lost and only one will develop into a mature egg ready to be fertilized.

Very few follicles remain by the time a woman reaches the menopause, usually between the age of 48 and 55.

John von RadowitzPress Association