A FREEZING process which improves the chances of embryos surviving post-thawing has been licensed in Ireland for the first time.
The Irish Medicines Board yesterday confirmed that the Merrion Fertility Clinic in Dublin is the first facility in the Republic which has been approved for vitrification, a technique that rapidly freezes embryos.
The process can also be used to freeze eggs and the clinic intends to establish an egg-freezing programme later this year pending a further licence from the Irish Medicines Board.
Dr Mary Wingfield, a consultant obstetrician and gynaecologist at the National Maternity Hospital, Holles Street, in Dublin, and medical director of the Merrion Fertility Clinic, said that, with the traditional slow method of freezing embryos, about 75 per cent of them survived the thawing process. She said that in the vitrification method up to 95 per cent of them survived.
“It means we can now freeze embryos using a method which has not been used in Ireland before,” Dr Wingfield said.
While it had been possible to successfully freeze sperm for many years, the fact that embryos and eggs contain more fluid, means there is a significantly greater risk of ice crystals forming, reducing the likelihood that the embryo will survive the thawing process.
Dr Wingfield said that because the chances of the embryo surviving the thawing process were now higher, it meant that the clinic could move towards its preferred option of single embryo implantation.
The clinic’s current practice is to implant two or three embryos, depending on a woman’s age, to improve the chances of conception.
However, she said that this also resulted in a higher likelihood of twin pregnancies, which had higher risks than pregnancies which involved one embryo.
“This is a new cryopreservation process to Ireland which offers a major leap forward in patient treatment opportunities,” she said.
“It supports our single embryo transfer programme which can improve overall outcome successes, reducing in-vitro fertilisation twin rates.”
She added that, pending a further licence from the Irish Medicines Board, the clinic intended to expand the vitrification process to include patients’ eggs later this year.
Dr Wingfield said that this would help women who, for example, had to have their ovaries removed or in cases of early onset menopause due to chemotherapy or radiology treatment programmes.
She said that while the new process would also allow women who are not in a position to conceive, and who are concerned about age-related fertility loss, to freeze eggs, this was not something that she would recommend to everyone.
“Mother Nature is still much better than technological means of conceiving and oocyte freezing is still a new technique.
“So my advice to all women is ‘plan early, don’t leave it too late’,” she said.