London: Treatment with common chemotherapy drug combination appears to increase the number of young eggs in women's ovaries, a new research has found.

Although it is too soon to link the outcome to fertility, researchers believe more research is needed to better understand the implications and findings of the study, published in the journal Human Reproduction.

If further research can reveal the mechanism by which treatment with the drug combination, known as ABVD, results in increased production of eggs, this would aid understanding of how women might be able to produce more eggs during their lifetime. This was until recently thought to be impossible.

"This study involves only a few patients, but its findings were consistent and its outcome may be significant and far-reaching. We need to know more about how this drug combination acts on the ovaries, and the implications of this," said lead researcher Evelyn Telfer, Professor at University of Edinburgh in Britain.

The researchers analysed samples of ovary tissue donated by 14 women who had undergone chemotherapy, and from 12 healthy women.

The study showed that the ovaries from eight of the cancer patients, who had been treated with a drug combination had a much greater incidence of immature, or non-growing, eggs compared with tissue from women who had received a different chemotherapy, or from healthy women of a similar age.

The ovary tissue was seen to be in healthy condition, appearing similar to tissue from young women's ovaries.

Researchers had set out to better understand why treatment with ABVD is one of the few cancer drug combinations that does not impact women's fertility.

Future studies will examine the separate impact of each of the four drugs that combine to make ABVD -- known as adriamycin, bleomycin, vinblastine and dacarbazine -- to better understand the biological mechanisms involved.