IVF practitioners disagree on whether embryo freezing could be totally replaced by a more “ethical” method suggested by the Health Minister, which involves freezing unfertilised eggs.
St James Hospital director Josie Muscat believes the technology will “change everything” and will soon become the accepted method in many places. But government expert Mark Brincat says the technology has been promised for 10 years and will never replace the need for embryo freezing.
Embryo freezing has been recommended by a parliamentary committee to reduce the incidence of multiple births, which increases the risk of problems in pregnancy. Without the facility to freeze embryos, all of them are transferred to the woman, as is the case in Malta.
“I don’t agree with embryo freezing,” Dr Muscat said, “because if couples don’t come back for the embryos, what do you do with them?”
This was a thorny issue discussed by the committee which eventually recommended that surplus embryos should be offered up for adoption.
Dr Muscat says a rather new technology, oocyte vitrification – that was mentioned as the preferred option of Health Minister Joseph Cassar – is still “experimental, like all methods of IVF” but is about to pass a very important stage of research.
He stresses that multiple births occur only in a small minority of cases and insists the media hype about the issue is inflated.
“Many women do not even get pregnant. Of the ones who do, the great majority are single births. A very small percentage are twins and a very, very, small percentage, are triplets. The chances are very low.”
He says the recent high-profile cases of several multiple births all at the same time (leading to overcrowding problems in hospital) was a “one-off” due to a particularly high success rate. Usually, he explains, fewer than three embryos are transferred because the others do not fertilise successfully.
He argues that if oocytes were frozen, these could be transferred two at a time and if they do not fertilise the process could restart with the remaining frozen oocytes.
“It will change everything,” Dr Muscat argues, adding that countries like Greece and Australia were already using the method.
But Prof. Brincat, director of obstetrics and gynaecology, who is also “keen on following developments”, points out this technology was promised 10 years ago but still has a “poor success rate”.
The former professor of reproductive medicine at the University of Nottingham says he was involved in this technology in the UK and provisions for freezing of oocytes were even made when the IVF unit at Mater Dei Hospital was designed and freezers were bought.
Yet, despite his excitement about this development, he feels it would not substitute the need to freeze embryos.
“You can’t just fertilise one or two oocytes and hope to get one or two embryos. A number simply won’t fertilise and you might end up with nothing to transfer in a stimulated cycle with all the expense, risk, psychological and physical trauma this entails.
“This is the Italian situation, where a lot was promised with oocyte freezing but expectations failed to materialise and they still ended with larger than desired multiple pregnancies,” he says, admitting technology has improved since then.
He believes oocytes should be frozen and a number of them fertilised in the hope of ending up with two or three embryos. If more than two embryos are fertilised, the rest should be frozen.
As vitrification becomes more efficient and yields better results, doctors could then rely less on embryo freezing but, in order to minimise risks and simplify the procedure, embryo freezing should always be allowed, he says.
“At the end of the day, all we are trying to do is help people with difficulties to have babies,” he stresses, arguing this is a difficult process which requires all the best tools available while keeping abreast of technology.
He adds frozen embryos are simply “one-day fertilised oocytes”, which may not have even reached a “two-cell” state as yet.
“In nature, the vast majority, some 80 per cent, do not survive.”