Researchers have reported that children born following an IVF treatments for male infertility are 51% more at risk of developing intellectual impairments than those born by normal conception.
Around half of the 48,000 IVF treatments carried out annually in Britain use this form of fertility treatment, known as intra-cytoplasmic sperm injection (ICSI).
It is used where the men are deemed to be almost completely infertile and involves injecting the sperm directly into their partner’s egg. However, the technique is already considered to be controversial as it has been linked to an increased risk of birth defects.
The study also found that in the most severe cases of male infertility, where men require surgery as part of the treatment, children were more than four times more likely to develop autism.
However, the number of men who undergo this are small so the numbers of actual cases are extremely low. Dr Avi Reichenberg, from the Institute of Psychiatry at King’s College London, who led the study, said: “About 50 per cent of IVF treatments use ICSI in the UK.
“Our study shows that these treatments developed to manage male infertility are associated with an increased risk for developmental disorders in the offspring.
“Whilst intellectual disability or autism remain a rare outcome for IVF, being aware of the increased risk associated with certain types of IVF means offspring at risk can be identified and potentially monitored for developmental disorders.”
The study, which is published in the Journal of the American Medical Association, analysed data from more than 2.5 million births in Sweden, of which 30,959 were conceived using IVF treatment.
They found that among those children who were conceived naturally, the risk of mental disability, defined by an IQ below 70 and an inability to perform every day skills such as learning, communication or social relationships, was just 62 out of every 100,000 births.
Standard IVF increased the risk by around 18 per cent, but when children who had been born as twins or triplets were taken into account this increase disappeared. This is because even naturally conceived twins and triplets have an increased risk of developing a mental disability in later life, however, mothers who undergo IVF are more likely to give birth to multiple children in one pregancy.
However, among those children conceived following IVF with ICSI, the risk increased by 51 per cent compared to natural conception, with 93 out of every 100,000 developing a mental disability. This remained high even after taking twins into account.
In the UK, this would be equivalent to 22 of the 24,000 births achieved using IVF with ICSI would have an intellectual disability. A subset of the patients who had received IVF with ICSI saw the men need surgery to retrieve their sperm. This increased the risk of the children developing severe autism by 4.6 times standard IVF.
However, the number of patients who have to undergo surgical ICSI are extremely low and when the researchers looked at children who had been born alone the risk disappeared. It is unclear why the risk is so much greater in multiple births using this technique than in the general population.
The researchers claim this presents a strong argument for an increase in the use of IVF techniques that transfer just a single fertilised egg into the mother as this would help to reduce the chance of twins or triplets being born. Dr Karl-Gösta Nygren, co-author of the paper from the department of medical epidemiology at Karolinska Institutet, said: “I find these results reassuring as the risk is very small. The risk of birth defects is much higher.
“Some of these risks are even preventable, so using single egg transfer could prevent multiple births for example. “There is a strong argument for extending the use of single egg transfer to diminish these risks.”
He added that it is likely the increased risk created by the use of ICSI is due to defects carried in the sperm rather from the procedure itself. The use of ICSI has attracted criticism in recent years as it can cause sperm that contain genetic defects to be selected and injected into an egg when they would not normally survive to make the arduous journey to the egg. It has also caused ethicists to question whether such techniques should be used as it circumvents one of the ways nature has evolved to prevent poor quality genes from being passed on.
A recent found, for example, that in 10 per cent of births using ICSI, the baby had a birth defect, compared to less than six per cent in natural births. Dr Alan Pacey, a fertility expert at the university of Sheffield and chairman of the British Fertility Society, said: “The main message of the paper is a positive one, suggesting that any risk of these disorders is very low in comparison to children conceived naturally.
“It does highlight the importance of preferentially using standard IVF rather than ICSI.” Between one and two per cent of the children born in the UK are conceived through IVF.
Sally Goddard Blythe, director of the Institute for Neuro-Physiological Psychology in Chester, which helps children with learning disabilities, said that she has noticed an increase in the number of children she was working with who had been conceived through IVF.
She said: “Over the past 20 years, we are seeing an increase in the percentage of children at an older age who were conceived as a result of IVF. “We have 75 to 80 new families coming in to see us a year. The incidence of IVF in their developmental history in the past two years is 10 per cent while 20 years ago
“Obviously there are more children being conceived through IVF but these figures still seem higher than they would normally be without it being an additional risk factor.” “More attention needs to be paid to this.”
Article: 4th July 2013 www.telegraph.co.uk