The recent birth in Belgium of a healthy baby girl, Tamara, has caused excitement throughout the world. Tamara is the first baby to be born to a woman after a frozen ovarian tissue transplant and despite the mother, Ms Touirat, being in a state of premature menopause provoked by the chemotherapy and the radiotherapy that had cured her of the cancer.
The revolutionary treatment was carried out by Professor Jacques Donnez and his team at the Cliniques Universitaires Saint-Luc with help from a new and sophisticated freezing equipment made by a British company. By the year 2010 it is estimated that about one in 250 people in the adult population will be childhood cancer survivors. Whilst 90% success rates can prevail for radio and chemotherapy treatment in such childhood treatments, ovaries are very sensitive to cytotoxic treatment and generally fertility function is compromised. The restoration of the ability to have children naturally after treatment is a high medical priority.
In this ground breaking case, part of Ms Touirat's left ovary was removed and the tissue was controlled rate frozen in a Planer step freezer before being stored in liquid nitrogen whilst therapy was undertaken. Some six years later tissue was implanted near Ms Touirat's fallopian tube and eggs were shortly produced, allowing a normal conception then to take place; on September 23, 2004 Tamara was finally born, weighing 3.72 kg. In their paper in the scientific journal The Lancet, the researchers say all the evidence they can see shows that the egg follicle, which ripened into the egg during the menstrual cycle in which Mrs Touirat became pregnant, came from the transplanted tissue.
The deep freezing of biological samples in liquid nitrogen has been used in hospital and veterinary medicine for some while. However, not all biological samples accept this process easily and Planer plc, a UK company based near London’s Heathrow airport, has been pioneering the use of specialist equipment for controlled rate freezing for these difficult but vital samples over the last thirty years. Its programmable step rate freezers allow the viable cryogenic preservation of samples such as skin, blood vessels, bone marrow, cord blood and other tissue that would otherwise not survive for long term storage in liquid nitrogen.
While sperm and embryos freeze and thaw relatively well, repeatability in human oocyte freezing is harder. However dramatic progress in oocyte preservation was also announced in September 2004 by Italian researchers Dr Raffaella Fabbri and her team. They say that they have achieved a breakthrough of thirteen live births using eggs that had been frozen from 68 different women. They also used the new versatile Planer freezer, similar to the one used by Prof Donnez. Their viability rate of 37% is a big step forward, but Dr Giovanni Coticchio leader of the research team at Bologna University, said that in future they hope to achieve a 75 to 85 per cent survival rate.
Planer plc was formed in 1973 makes the only freezers that can cope with the differing requirements for embryo, oocytes and tissue freezing. Amongst many other achievements a Planer freezer was used in the first human birth from a frozen embryo in 1983 and also the first human birth from a frozen oocyte in 1997. Thousands of researchers, IVF labs, vets and doctors now use Planer freezers around the world.
Photo shows Ouarda Touirat and Tamara with cryogenic freezing equipment used to freeze her tissue.