The UK's fertility treatment regulator, the Human Fertilisation and Embryology Authority (HFEA), is likely to recommend that women undergoing IVF treatment should only be allowed to have one embryo transferred at a time.
The HFEA last reviewed its guidelines on how many embryos can be implanted during IVF treatments in July 2005. At the time, over 90 per cent of IVF cycles in the UK involved the transfer of two or three embryos. The HFEA was considering limiting IVF treatments to the transfer of a single embryo per cycle, as has been done in some other European countries. Current guidance, found in the HFEA Code of Practice, stipulates that clinics should transfer no more than two eggs or IVF embryos at a time to women under 40 years old and no more than three eggs or embryos to women older than 40. Implanting more than one embryo can increase the chance of having a successful outcome - but it also increases the incidence of twin births, which puts increased strain on intensive care and neonatal units.
Professor Peter Braude, chair of the HFEA's working group on multiple pregnancies, said that twins were a complication of IVF pregnancies, not a bonus. 'The public does not realise that twins are a health risk', he said, adding that 'the need to tackle the problem is unequivocal. Neonatal units are stretched to the extent that you cannot always get your baby into one'.
The group is expected to highlight the costs - in both financial and medical terms - of twin births and to recommend that only one embryo at a time be transferred into women aged 35 or under - other embryos can be placed in frozen storage to be used at another time or if pregnancy is not achieved on the first attempt. In terms of funding, the group is expected to say that the first attempt with a fresh embryo, as well as a second attempt if the first is unsuccessful, should be funded by the NHS.
John Paul Maytum, a spokesman for the HFEA, said that the authority would wait to see the group's full report before making any decisions on how to reduce multiple births, adding that it would need to come up with a 'workable' solution. 'There is a lot of anxiety among patients about this, with the belief that if you have just one embryo, there is less chance of success and you will have to go through it again', he said.
Earlier this year, a study on the effect of single embryo transfer (SET) on pregnancy rates triggered further calls for the HFEA to stick with its existing policy. The research, published in the journal Human Reproduction, showed that imposing a single embryo limit on all women undergoing fertility treatment - irrespective of their age or embryo quality - would halve the pregnancy rate per cycle of IVF. But in June, statistics produced by the European Society of Human Reproduction and Embryology (ESHRE) showed that SET is a trend that appears to be continuing, being favoured in many countries, especially the Nordic countries and Belgium. Professor Anders Nyboe Andersen, who presented the data, said at the time that 'in Sweden today there is 70 per cent elective SET, which has resulted in a decline in twin birth rates to five per cent, which is sensational'.
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Couples face ban on IVF twins