Lyon, France: The first baby to be created from an egg that had been matured in the laboratory, frozen, thawed and then fertilised, has been born in Canada. Three other women are pregnant by the same process. The research was presented to the 23rd annual meeting of the European Society of Human Reproduction and Embryology today (Monday 2 July).
The baby girl was born to one of 20 patients with polycystic ovarian syndrome (PCOS) or with ovaries that had been detected to be polycystic by ultrasound (U/S), who took part in the trial at McGill Reproductive Center, Montreal, Canada. The baby is progressing well.
Dr Hananel Holzer, who led the team, is an assistant professor at the Center and coordinates the fertility preservation programme there . He said: Freezing a womans eggs (or oocytes) has become an important and integral part of fertility treatment, and the introduction of new freezing techniques such as oocyte vitrification has increased significantly both oocyte survival and resulting pregnancy rates. However, to date, the pregnancies reported have been the result of fertilisation of frozen or vitrified and then thawed oocytes that had been collected after ovarian stimulation. Unfortunately, some patients seeking fertility preservation may not have enough time to undergo ovarian simulation, or may suffer from a medical condition deemed by some oncologists as a relative contraindication to hormonal stimulation, such as oestrogen-receptor-positive breast cancer.
In these circumstances, oocytes can be collected from the ovaries without hormonal stimulation, and the immature oocytes can be matured in the laboratory before being frozen or vitrified. But, until now, it was not known whether oocytes collected from unstimulated ovaries, matured in vitro and then vitrified, could survive thawing, be fertilised successfully and result in a viable pregnancy after embryo transfer.
We have demonstrated for the first time that it
Contact: Emma Mason
European Society for Human Reproduction and Embryology