Babies conceived through some test-tube techniques could be at significantly higher risk of long-term health problems in later life than children conceived naturally, a fertility specialist said yesterday.
Lord Winston, professor of fertility studies at Imperial College in London, said not enough research had been done on many of the new technologies that had been introduced into IVF clinics.
He said the lack of research led to a situation in which couples did not receive enough information on the risks, making a mockery of the "informed consent" they were required to give by law.
"I'm not arguing that IVF is dangerous, what I am arguing is that there actually isn't any form of properly informed consent. I'm calling for more research so there could actually be better informed consent," Lord Winston told the British Association for the Advancement of Science at Salford University.
He said a number of studies on IVF children, especially those who were conceived using the injection of single sperm directly into an egg, or those whose embryos had been frozen, pointed to an increased health risk.
"Whilst the early reports of IVF were wholly reassuring in terms of the abnormality rate, there is now a lot of data out there in the public arena which suggests that some procedures actually, under certain circumstances, might be quite dangerous," he said.
One study found that there were considerable "potential changes" in animal embryos after they were frozen, yet this research was dismissed by the medical profession when it was first published in 1995, on the basis that it was irrelevant to humans
"I wondered whether this was partly because of the way that IVF was being delivered, which was essentially through the commercial sector in nearly every country. To my mind that's a disadvantage," Lord Winston said. "Nobody has looked at mutation rates after the freezing of these cells and that seems to me to be a critical question."
A study by one of Lord Winston's researchers, Maria Tachataki, found that embryo-freezing appeared to affect a critical tumour-suppressor gene, which has the job of preventing cancer.
"There is one particular tumour suppressor-gene that we've been looking at which under certain circumstances, under certain kinds of embryo freezing, it appears that gene expression is actually altered as a result of freezing," he said.
"Those sorts of untold effects are things that we should be chasing more vigorously, given the fact that there is a background in some parts of the world of a surprisingly high abnormality rate after IVF."
A review of babies born by intracytoplasmic sperm injection - a procedure developed to help couples having IVF because of male infertility - found they suffered a 9.5 per cent risk of abnormality, which was two and a half times higher than typical abnormality rates.
Another study of more than three million babies found that IVF babies were more than twice as likely to have low birthweights compared with the general population.
"Low birthweight has implications for later health. If you have a small baby you are more likely under certain circumstances to develop vascular disease, hypertension, possibly osteoporosis and diabetes by the age of 60," he told the conference.
"I'm not saying we should stop any of these treatments. They are useful, but we should not be embarking on treatments that are not seen as essential to the patients. The problem is that we are doing things in the laboratories which are not actually being tested as they should be.
"Even in terms of the drugs we give to stimulate the ovaries, there is a surprising lack of information about what the risk might be to the gametes [sperm and eggs], for instance, what risk there might be to chromosomal abnormalities in the eggs."Reuse content