Frozen ovary hope for sterile cancer patients

WOMEN made infertile by intensive cancer treatment could soon benefit from a technique being developed to transplant frozen tissue from ovaries.

US scientists removed ovarian tissue from a 30-year-old woman before she underwent chemotherapy for breast cancer, leaving her infertile.

Six years later, the tissue was placed under the skin of her abdomen, with ovarian function returning after three months and eggs being harvested.

Using in-vitro fertilisation (IVF) treatment, the scientists managed to produce a four-cell embryo which was implanted into the woman’s womb, although she failed to become pregnant.

It is the first time this technique has been shown to be able to produce normal embryos in humans.

The research is published in The Lancet online.

Last October, US scientists revealed they had produced the first live birth from transplanted ovarian tissue in a rhesus monkey, with the hope this could soon be done in a human.

Now the team from the Centre for Reproductive Medicine and Infertility at New York Presbyterian Hospital have moved a step closer to this aim with their partial success in humans.

Lead researcher Kutluk Oktay said: “This research represents a potentially significant reproductive advancement in two respects.

“First, women can preserve their fertility by freezing their ovarian tissue, and second, pregnancy may be possible even after the tissue remains frozen for a long time.”

Every year hundreds of thousands of women around the world are left infertile because radiotherapy, chemotherapy and radical surgery.

The researchers concluded: “Even though the final proof of success of ovarian cryo-preservation and transplantation procedure will be a viable pregnancy in human beings, with the development of a human embryo, prospects for a pregnancy and liveborn are now more promising.”

But Johan Smitz, from the Centre for Reproductive Medicine at University Hospital in Brussels, warned that these techniques were not without risk.

In an accompanying commentary, he said that due to uncertainty about the effectiveness and safety of ovarian cryogenic storage and grafting, the procedures should be presented to patients as experimental.

“Only a small part of the ovarian graft can be screened with sensitive techniques for the detection of hosted cancer cells.

“For some cancers, it will be always difficult to completely exclude the presence of such cells in the graft.”

Dr Smitz called for much larger trials involving girls and young women at immediate risk of becoming infertile.